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M-type asteroid

M-type (aka M-class) asteroids are a spectral class of asteroids which appear to contain higher concentrations of metal phases (e.g. iron-nickel) than other asteroid classes, and are widely thought to be the source of iron meteorites.

Definition
Asteroids are classified as M-type based upon their generally featureless and flat to red-sloped absorption spectra in the visible to near-infrared and their moderate optical albedo. Along with the spectrally similar E-type and P-type asteroids (both categories E and P were formerly type-M in older systems), they are included in the larger X-type asteroid group and are distinguishable only by optical albedo:

 * P-type || albedo < 0.1
 * M-type || albedo in 0.1 ... 0.3
 * E-type || albedo > 0.3
 * }
 * E-type || albedo > 0.3
 * }
 * }

Composition
Although widely assumed to be metal-rich (the reason for use of "M" in the classification), the evidence for a high metal content in the M-type asteroids is only indirect, though highly plausible. Their spectra are similar to those of iron meteorites and enstatite chondrites, and radar observations have shown that their radar albedos are much higher than other asteroid classes, consistent with the presence of higher density compositions like iron-nickel. Nearly all of the M-types have radar albedos at least twice as high as the more common S- and C-type, and roughly one-third have radar albedos ~3× higher.

High resolution spectra of the M-type have sometimes shown subtle features longward of 0.75 μm and shortward of 0.55 μm. The presence of silicates is evident in many, and a significant fraction show evidence of absorption features at 3 μm, attributed to hydrated silicates. The presence of silicates, and especially hydrated silicates, is at odds with the traditional interpretation of M-types as remnant iron cores.

Bulk density and porosity
The bulk density of an asteroid provides clues about its composition and meteoritic analogs. For the M-types, the proposed analogs have bulk densities that range from ~3 $g/cm3$ for some types of carbonaceous chondrites up to nearly 8 $g/cm3$ for the iron-nickel present in iron-meteorites. Given the bulk density of an asteroid and the density of the materials that make it up (aka particle or grain density), one can calculate its porosity and infer something of its internal structure; for example, whether an object is coherent, a rubble pile, or something in-between.

To calculate the bulk density of an asteroid requires an accurate estimate of its mass and volume; both of these are difficult to obtain given their small size relative to other solar system objects. In the case of the larger asteroids, one can estimate mass by observing how their gravitational field affects other objects, including other asteroids and orbiting or flyby spacecraft. If an asteroid possesses one or more moons, one can use their collective orbital parameters (e.g. orbital period, semimajor axis) to estimate the masses of the ensemble, for example in the two-body problem.

To estimate an asteroid's volume requires, at a minimum, an estimate of an asteroid's diameter. In most cases, these are estimated from the visual albedo (brightness) of the asteroid, chord-lengths during occultations, or their thermal emissions (e.g. IRAS mission). In a few cases, astronomers have managed to develop three-dimensional shape models using a variety of techniques (c.f. 16 Psyche or 216 Kleopatra for examples) or, in a few lucky instances, from spacecraft imaging (c.f 162173 Ryugu).

Of these, mass measurements made via spacecraft deflection or the orbits of moons are considered the most reliable. Ephemeris estimates are based on the subtle gravitational pull of other objects on that asteroid, or vice versa, and are considered less reliable. The exception to this caveat may be Psyche, as it is the most massive M-type asteroid and has numerous mass estimates. Size estimates based on shape models (usually derived from adaptive optics, occultations, and radar imaging) are the most reliable. Direct spacecraft imaging (Lutetia) is also quite reliable. Sizes based on indirect methods like thermal IR (e.g. IRAS) and radar echoes are less reliable.

None of the M-type asteroids have bulk densities consistent with a pure iron-nickel core. If these objects are porous (aka rubble-piles), then that interpretation may still hold; this is unlikely for Psyche, because of its large size. Given the spectral evidence of silicates on most M-type asteroids, the consensus interpretation for most of these larger asteroids is that they are composed of lower density meteorite analogs (e.g. enstatite chondrites, metal-rich carbonaceous chondrites, mesosiderites), and in some cases may also be rubble piles.

Formation
The earliest interpretation of the M-type asteroids was that they were the remnant cores of early protoplanets, stripped of their overlying crust and mantles by massive collisions that are thought to have been frequent in the early history of the solar system.

It is acknowledged that some of the smaller M-type asteroids (<100 km) may have formed in this way, but that interpretation was challenged for 16 Psyche, the largest of the M-type asteroids. There are three arguments against Psyche forming in this way. First, it must have started as a Vesta-sized (~500 km) protoplanet; statistically, it is unlikely that Psyche was completely disrupted while Vesta remained intact. Second, there is little or no observational evidence for an asteroid family associated with Psyche, and third, there is no spectroscopic evidence for the expected mantle fragments (i.e. olivine) that would have resulted from this event. Instead, it has been argued that Psyche is the remnant of a protoplanet that was shattered and gravitationally re-accumulated into a well-mixed iron-silicate object. There are numerous examples of metal-silicate meteorites, aka mesosiderites, that might be objects from such a parent body.

One possible response to this second interpretation is that the M-type asteroids (including 16 Psyche) accumulated much closer to the Sun (1–2 au), were stripped of their thin crust/mantles while still molten (or partially so), and later dynamically moved into the current asteroid belt.

A third view is that the largest M-types, including 16 Psyche, may be differentiated bodies (like 1 Ceres and 4 Vesta) but, given the right mix of iron and volatiles (e.g. sulfur), these bodies may have experienced a type of iron volcanism, a.k.a. ferrovolcanism, while still cooling.

Notable examples
In the JPL Small Body Database, there are 980 asteroids classified under the Tholen asteroid spectral classification system. Of those, 38 are classified as M-type. Another 10 were originally classified as X-type, but are now counted among the M-types because their optical albedos fall between 0.1 and 0.3. Overall, the M-types make up approximately 5% of the asteroids classified under the Tholen taxonomy.

(16) Psyche
16 Psyche is the largest M-type asteroid with a mean diameter of 222 km, and has a relatively high mean radar albedo of $$\hat{\sigma}_{OC}=0.34 \pm 0.08 $$ suggesting it has a high metal content in the upper few meters of its surface. The Psyche spacecraft was launched on october 13th, 2023 is en route to visit 16 Psyche, arriving in 2029.

(21) Lutetia
21 Lutetia has a mean diameter of 100 km, and was the first M-type asteroid to have been imaged by a spacecraft when the Rosetta space probe visited it on 10 July 2010. Its mean radar albedo of $$\hat{\sigma}_{OC}=0.24 \pm 0.07 $$ is roughly twice that of the average S-type or C-type asteroid, and suggests its regolith contains an elevated amount of metal phases relative to other asteroid classes. Analysis using data from the Rosetta spectrometer (VIRTIS) was consistent with estatitic or iron-rich carbonaceous chondritic materials.

(22) Kalliope
22 Kalliope is the second largest M-type asteroid with a mean diameter of 150 km. A single moon, named Linus, was discovered in 2001 and allows for an accurate mass estimate. Unlike most of the M-type asteroids, Kalliope's radar albedo is 0.15, similar to the S- and C-type asteroids, and does not suggest an enrichment of metal in its regolith. It has been the target of high resolution adaptive optics imaging which has been used to provide a reliable size and shape, and a relatively high bulk density of 4.1 $g/cm3$.

(216) Kleopatra
216 Kleopatra, with a mean diameter of 122 km, is the third largest M-type asteroid known after 16 Psyche and 22 Kalliope. Radar delay-Doppler imaging, high-resolution telescopic images, and several stellar occultations show it to be a contact binary asteroid with a shape commonly referred to as a "dog-bone" or "dumbbell." Radar observations from the Arecibo radar telescope indicate a very high radar albedo of $$\hat{\sigma}_{OC}=0.43 \pm 0.10 $$ in the southern hemisphere, consistent with a metal-rich composition. Kleopatra is also notable for the presence of two small moons, named Alexhelios and Cleoselena, which have allowed its mass and bulk density to be accurately computed.

title: M-type asteroid


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E-type asteroid

E-type asteroids are asteroids thought to have enstatite (MgSiO3) achondrite surfaces. They form a large proportion of asteroids inward of the asteroid belt known as Hungaria asteroids, but rapidly become very rare as the asteroid belt proper is entered. Some are quite far from the inner edge of the asteroid belt, such as 64 Angelina. They are thought to have originated from the highly reduced mantle of a differentiated asteroid.

Description
E-type asteroids have a high albedo (0.3 or higher), which distinguishes them from the more common M-type asteroids. Their spectrum is featureless flat to reddish. Probably because they originated from the edge of a larger parent body rather than a core, E-types are all small, with only three (44 Nysa, 55 Pandora, 64 Angelina) having diameters above 50 kilometres and no others above 25 kilometers (the biggest three also orbit atypically far, c. 3 AU, from the Sun). Aubrites (enstatite achondrite meteorites) are believed to come from E-type asteroids, because Aubrites could be linked to the E-type asteroid 3103 Eger.

This grouping may be related to the Xe-type of the SMASS classification.

E-Belt
The E-type asteroids of the Hungaria family are thought to be the remains of the hypothetical E-belt asteroid population. The dispersal of most of that hypothetical E-Belt might have been caused by the outward migration of the gas giants of the Solar System according to simulations done under the Nice model – and these dispersed E-Belt asteroids might in turn have been the impactors of the Late Heavy Bombardment.

Exploration
On September 5, 2008, ESA's robotic spaceprobe Rosetta visited the E-type asteroid 2867 Šteins. Spectral data from the spacecraft confirmed the asteroid was composed mainly of iron-poor minerals such as enstatite (magnesium-rich pyroxene), forsterite (magnesium-rich olivine) and feldspar.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: E-type asteroid


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Seventy (Latter Day Saints)

Seventy is a priesthood office in the Melchizedek priesthood of several denominations within the Latter Day Saint movement, including the Church of Jesus Christ of Latter-day Saints (LDS Church). Traditionally, a Latter Day Saint holding this priesthood office is a "traveling minister" and an "especial witness" of Jesus Christ, charged with the mission of preaching the gospel to the entire world under the direction of the Twelve Apostles. Latter Day Saints teach that the office of seventy was anciently conferred upon the seventy disciples mentioned in the Gospel of Luke. Multiple individuals holding the office of seventy are referred to collectively as "seventies".

Place in Latter-day Saint hierarchy
In practical terms, the priesthood office of seventy is one which has varied widely over the course of history. As originally envisioned by Latter-day Saint movement founder Joseph Smith in the 1830s, the seventy were to be a body composed of several separate quorums of up to 70 seventies each, all of which would be led by seven presidents. These presidents, chosen from the first quorum, would appoint and direct the other quorums of seventy.

In the LDS Church, the largest of the Latter Day Saint denominations, the quorums of the seventy are directed and supervised hierarchically by the Quorum of the Twelve Apostles, who are in turn directed by the First Presidency. As introduced by Smith, the apostles and the seventy had authority only outside the main body of Latter-day Saints in Zion, and in the outlying stakes. Members in Zion and the stakes were led by the High Council of Zion (under the direction of the First Presidency) and stake high councils.

As a body, the seventy in the LDS Church are considered to be equal in priesthood authority with the Quorum of the Twelve Apostles. This presumably means that if the apostles were killed or incapacitated, the seventy could take over the function of the apostles. However, in such circumstances, the seventy would be required to act unanimously.

Early Latter-day Saint quorums of seventy
Historically, the First Quorum of the Seventy came into being in 1835 when seven men were set apart as the First Seven Presidents of the Seventy.

In 1837, six of the seven presidents were released because it was discovered that they had previously been ordained high priests. Five of these men were ultimately replaced by others. The other two—Levi W. Hancock and Joseph Young—remained members of the First Seven Presidents for the rest of their lives.

The Church of Jesus Christ of Latter-day Saints
Since 2020, the Quorums of the Seventy in the LDS Church have been organized into twelve quorums with a presidency of seven. The seventy act as emissaries of the Quorum of the Twelve Apostles and First Presidency of the church in organizing, training, proselytizing, and administering to millions of people scattered all across the globe. The seventy are the layer between local church administration and general church administration.

Members of the First and the Second Quorums of the Seventy are general authorities of the church with responsibilities covering the church as a whole.

Members of the Third through Twelfth Quorums of the Seventy are called an area seventy and are ordained to the priesthood office of seventy, but they are not general authorities of the church. Area seventies generally have authority only within a geographical unit of the church called an area.

Community of Christ
Within Community of Christ, a seventy is also considered to be an elder but is not a High Priest. Part of the function of the seventy is a missionary role and he or she works closely with the apostle in charge of his or her mission field. Seventies are organized into nine quorums; each quorum being presided over by a president. These presidents make up the Council of Presidents of Seventy and are collectively led by the Senior President of the Presidents of Seventy. All nine quorums are equal with one another. When someone is ordained a seventy, that person automatically becomes a member of one of the Nine Quorums, and remains a member of one of the Quorums (although the specific quorum may change based on residency) so long as that person remains a seventy. In other words, it is not possible to be a seventy and not belong to one of these quorums.

The current roster of Presidents of Seventy include:

 * Africa Quorum - Larry M. McGuire
 * Canada, Dominican Republic, & Mexico Quorum - John F. Glazer
 * Central & South America Quorum - Humberto Rosario del Rosario
 * Eurasia Quorum - Joey S. Williams
 * Pacific Asia Quorum - Adam R. Wade
 * South Central Asia Quorum - Larry M. McGuire
 * Central & Northeast USA Quorum - Joelle Wight
 * North Central & Western USA Quorum - Karin F. Peter, Senior President of Seventy
 * Southern USA Quorum - Larry M. McGuire

Historically, there have always been seven quorums, with a maximum of 70 members each. However, on January 17, 2010, Prophet-President Stephen M. Veazey announced that the number of quorums (and presidents) could be flexible, based on the current needs of the church. The change from seven to ten quorums occurred after the acceptance of Doctrine and Covenants section 164 at the World Conference in April 2010.

The Church of Jesus Christ (Bickertonite)
The seventy in this church are called the Seventy Evangelists and strictly limited to that number. They are ordained evangelists, not seventies. Missionary work is the focus of this calling in The Church of Jesus Christ.

Apostolic United Brethren
There is currently one functioning Quorum of Seventy in the Apostolic United Brethren. Its members are distributed geographically among AUB congregations, with men ordained to this office called for life.

title: Seventy (Latter Day Saints)


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Indian Institute of Management Ahmedabad

Indian Institute of Management Ahmedabad (IIM Ahmedabad or IIM-A), is an Indian business school, located in Ahmedabad, Gujarat, India. As one of India's premier Indian Institutes of Management, the school has been accorded the status of an Institute of National Importance by the Ministry of Human Resources, Government of India in 2017. It is widely regarded as the leading business school in India and one of the most prestigious business schools in the world.

Established in 1961, the institute offers master's degree programs in management and agri-business management, a fellowship program and a number of executive training programs. The institute's founding director is Ravi J. Matthai. Other notable founding figures were the Indian physicist Vikram Sarabhai, Indian businessman Kasturbhai Lalbhai and Indian educator Kamla Chowdhary.

History
IIM Ahmedabad was established on 11 December 1961 with the active support of the Government of India, the Government of Gujarat, Harvard Business School, and prominent members of Indian industry. The physicist Vikram Sarabhai and businessman Kasturbhai Lalbhai, both natives of Ahmedabad, played pivotal roles in setting up the institute. The institute's Kasturbhai Lalbhai Management Development Centre and a Kasturbhai Lalbhai Chair in Entrepreneurship are named in his honor. The management educator Ravi J. Matthai and several other Ahmedabad-based businessmen also played a major role in its creation. Kamla Chowdhary was the first faculty of the institute, and the coordinator of programmes between 1962 and 1965. The institute offers master's degree programs in management and agri-business management, a fellowship program and a number of executive training programs. The institute's founding director was Ravi J. Matthai. Other notable founding figures were the Indian physicist Vikram Sarabhai, Indian businessman Kasturbhai Lalbhai and Indian educator Kamla Chowdhary. In 2020 it was ranked first among the business schools in India by the National Institutional Ranking Framework. During the period 2017–21, it has been ranked first amongst the management institutions.

Campus
The IIM Ahmedabad campus is situated across 102 acres in Vastrapur, Ahmedabad. The campus houses the academic blocks, faculty offices, student and faculty accommodation, the Vikram Sarabhai Library, the R.J. Matthai Auditorium, the Louis Kahn Plaza, the International Management Development Centre, the Kasturbhai Lalbhai Management Development Centre, the Centre for Innovation, Incubation and Entrepreneurship, sport facilities, several food outlets and merchandise stores.

Overseas Extension Centre in Dubai
In collaboration with UAE-based BRS Ventures, IIM Ahmedabad has signed an agreement to establish its first overseas extension centre in Dubai. The centre aims to offer executive education programmes that are relevant to the region, including both open learning and customised training programmes. This move is part of IIM Ahmedabad's global outreach, making it the first IIM to potentially establish a full-fledged overseas campus. The development is in line with the National Education Policy, which encourages high-performing Indian universities to set up campuses in other countries.

Architecture
In 1962, the IIM Ahmedabad board came to a formal agreement with the National Institute of Design (NID) for the latter to undertake the task of designing the IIM Ahmedabad campus. The National Institute of Design appointed American architect Louis Kahn and B.V. Doshi as architects for the project. Kahn worked on the IIMA project from 1962 until his death in 1974.

Kahn's architecture is characterized by the use of exposed red bricks, the extensive use of geometric shapes in hostels and academic blocks and vast corridors outside the classrooms. He combined Indian traditional and vernacular architecture and modern architecture skillfully. A number of tourists and architecture students often visit the campus for its phenomenal architectural impact.

Vikram Sarabhai Library
The library is named after the institute's founder, renowned physicist Vikram Sarabhai. The library was instituted in 1962 and houses over 193000 books and has online subscriptions to greater than 24000 journals. The library provides access to 100+ digital databases relating to scholarly, company and industry information to the IIMA community. The library is located at the Louis Kahn Plaza. In year 2016, Tata Consultancy Services partnered with the university with a grant of inr 200000000 to restore the library for digital learning and collaboration. In 2019, the library received Award of Distinction' at the UNESCO Asia Pacific Award for Cultural Heritage Conservation 2019.

Student accommodation
Students are provided single room accommodation in the 33 fully furnished dormitories spread across the campus. Married students can opt to live with their family in married students' hostels. Stay in dormitories is mandatory for students. Basic amenities including washing machines, refrigerators and TVs are available at each dorm.

Logo
The logo of the institute has the motif of the 'Tree of Life'. The logo is inspired by a carved stone latticework jaali in the 16th century mosque of Siddi Saiyyad in old part of Ahmedabad. The Sanskrit phrase 'vidyaviniyogaadvikasah' embedded in the logo was given by Professor H.N. Pathak in the 1960s in response to a competition organized by Prof. Ravi J. Matthai, which translates to "it is the application of knowledge that leads to one's overall development."

Schools

 * JSW School of Public Policy - Set up with financial contribution from JSW Steel Ltd worth Rs. 50 crore, the school is engaged in research on policy formulation and design, policy choice, and policy impact.

Research centers
The university has the following sector or mission oriented centres which are staffed by faculty members:
 * Centre for Innovation, Incubation & Entrepreneurship (CIIE) – It was originally set up in 2012 as a research institution, with a grant pool from Government of Gujarat, the Department of Science and Technology (DST) and IIMA. It now operates as a section 8 non profit company under Companies Act 2013. The centre supports 40–60 ventures every year through its accelerator programs, incubation spaces and seed investment program. The centre has about 20,000 sq ft of incubation space in Ahmedabad, 30,000 sq ft in Pune and is in the process of setting up another one in Pune spread over 10,000 sq ft. The center also has a Young IIMAvericks Fellowship/Internship program for batch of graduating students who decide to take the route of entrepreneurship. In 2015, CIIE was invited to co-host the first India-US Startup Konnect in the Silicon Valley to showcase the strengths of India's startup ecosystem. In 2017, Securities and Exchange Board of India gave approval to Bharat Innovation Fund to operate as a Venture Capital Fund and also secured Category – I Venture Capital Fund status.
 * India Gold Policy Centre
 * Centre for Management of Health Services
 * Gender Centre
 * Misra Centre for Financial Markets and Economy
 * NSE Centre for Behavioral Science in Finance, Economics and Marketing
 * Centre for Transportation and Logistics
 * Centre for Digital Transformation
 * Ashank Desai Centre for Leadership and Organisational Development (CLOD)
 * Centre for Digital Transformation, set up in collaboration with Bank of America
 * Arun Duggal ESG Centre for Research and Innovation

Library
The Vikram Sarabhai Library is a biggest central library in India located on the campus of the Indian Institute of Management (IIM) in Ahmedabad, Gujarat, India. It is named after Dr. Vikram Sarabhai, who was a renowned physicist and industrialist, and is considered to be the father of the Indian space program.

The library is spread over an area of approximately 30,000 square feet and is one of the largest management libraries in Asia. It has a collection of over 1,00,000 books, 10,000 journals and other resources in various fields of management, economics, social sciences, and humanities.

The library provides access to various online databases, e-journals, e-books, and other digital resources. It also has a state-of-the-art auditorium, discussion rooms, and a computer lab for the use of students and faculty members.

The library is open to all IIM students, faculty members, and staff. It is also open to external users, who can access the library's resources by obtaining a membership. The library has a friendly and helpful staff that assists users in finding the resources they need and in using the library's facilities.

Academics
IIM Ahmedabad offers various full-time and part-time postgraduate programmes, leading to an MBA degree. It also offers diploma programmes.

Exchange programs
IIMA has affiliations with 78 leading business schools across the world. In 2015–16, 140 students from IIMA spent a semester at affiliate business schools across North America, Europe, Africa, Australia, and the Asia Pacific region, while 87 students from foreign colleges spent a semester at IIMA for the same period. The institute has a Dual Degree and one term exchange programs arrangement with a few business schools such as HEC Paris, Bocconi University, EDHEC Business school, University of Louvain, ESSEC Business School in Paris, University of Cologne, ESCP Europe and Emlyon Business School. Some of the students going on exchange receive scholarships from the institute, DAAD Germany, the French Government and participating schools.

Admission
IIMA offers different academic programs and has admission processes and eligibility respectively. The IIMA admission process is based on the course candidate opt for. CAT score is the basic exam to apply for admission in PGP, PGP-FaBM, ePGP and ePGD-ABA. Admission to PGPX is on the basis of GMAT/GRE only. Apart from that, they accept applications from other entrance exams like GRE, GMAT, GATE, UGC-JRF & ICAR-SRF. The next major aspect for admission is the category (GEN & EWS, NC & OBC, SC, ST, PWD & PWD (ST) ), Total seats are further divided into the category where IIM accept admission on the category basis. Good academic record and percentage score is another major aspect.

IIM also conducts its analytics writing test and personal interview (AWT & PI) in Ahmedabad, Bangalore, Hyderabad, Kolkata, & New Delhi cities of selected candidates. Seats in IIMA are reserved, based on government instruction 27% of seats are reserved for NC-OBC,  15% for SC, 7.5% for ST candidates, 5% for Persons with Benchmark Disabilities (PwD), and up to 10% for Economically Weaker Sections (EWS).

Rankings
In India, IIM Ahmedabad was ranked first among management schools in India by the National Institutional Ranking Framework in 2023 for the second year with an overall score of 83.20.

QS ranked it 44 in the world and 8 in Asia in its Global MBA Rankings 2023. QS also ranked its Two Year MBA programme (PGP) at rank 42 in its World University Rankings - Masters In Management 2024

The Two Year MBA programme (PGP) of IIM Ahmedabad was ranked by Financial Times at rank 43 in its global Masters in Management Ranking 2023, with Career Progress rank 19 and Alumni Network rank 11.

The Financial Times has ranked the One Year MBA programme (PGPX) of IIM Ahmedabad at rank 41 in its Global MBA Ranking 2024.

Outlook India's "Top Public MBA Institutions In India" survey. It was ranked second by Business Today "India's Top Five B-Schools Yearly Ranking In 2022". It was ranked 51 by The Economist in its 2021 Full-time B-school ranking.

The Red Brick Summit (TRBS)
The Red Brick Summit or TRBS, named after the red brick walls that the campus is known for, replaced 'Big Four' individual management fests/summits (Confluence, Amatheon, ConneXions, and Insight) as an umbrella management symposium. Instituted in 2017, the mega event – the biggest management symposium in Asia with a footfall of 20,000 students across more than 250 Indian and 30 international universities – sees renowned speakers talking about issues relevant to management and public policy, national-level business competitions, and workshops attended by hundreds. The speakers include Nirmala Sitharaman (Union Cabinet Minister, Defence), Maneka Gandhi (Union Cabinet Minister, Women and Child Development), Hasmukh Adia (Revenue Secretary, Government of India), and Deep Kalra (Founder-CEO of MakeMyTrip).

Chaos
Chaos is the annual cultural festival of IIMA. Its yearly editions have been centred on themes like diversity, colour or going green. The cultural festivities draws footfalls of around 50,000 visitors from Ahmedabad over four days and participation from institutes across the country. Pro-nites (events hosted by professional artists) are especially a huge success with a large number of top class artists coming and performing on one stage. In the past, Chaos has witnessed musical performances by Jagjit Singh, Amit Trivedi, Raghu Dixit, Mohit Chauhan, Armaan Malik and Shankar–Ehsaan–Loy to name a few.

Placements
The placement process at IIM Ahmedabad is a student-driven process that institutionalizes placements for the entire batch. The Placement Committee elected by the student liaisons between the Institute administration, students, and recruiters. Placements for the PGP and PGP-FABM courses are characterized by two phases – summer placements for the first-year batch and final placements for the graduating batch. The summers process is conducted in Nov/Dec for the first year. The second-year placement committee handles the process for them. The placement process for graduating is conducted in two stages. The first is the laterals process in January where firms interview students with prior work experience and offer them mid-level managerial positions. The second stage is the final placement process in around February. This process is handled by the newly elected committee among the PGP1s to avoid any conflict of interest and ensure a fair process. Companies from multiple sectors across different geographies hire candidates for a wide range of functions

Business
IIMA has been instrumental in influencing the business landscape of the country, with the highest proportion of BSE 500 CEOs (who have an MBA) coming from IIMA. More than 400 students provide live consulting for businesses through the Forum for Industry Interaction annually. 84 projects were undertaken by students in 2015.

Monetary Policy
IIMA has played a key role in India's monetary policy - four Governors of the Reserve Bank of India have been associated with IIMA (three as faculty - C. Rangarajan, I. G. Patel, and Y. V. Reddy, and one as student - Raghuram Rajan). Two faculty members (Ravindra Dholakia and Jayanth Varma ) have been members of the Monetary Policy Committee (India).

Public Policy
A key study by IIMA on salaries in the private and public sector helped shape the 7th Central Pay Commission's recommendations. Professors from IIMA have been appointed to eminent panels and committees, responsible for shaping key policies, by the government. IIMA's Gold Policy Centre is in the process of publishing a paper on the government's Gold Monetization Policy. The Punjab Prisons Department has signed a MoU with IIMA for a prison modernization project. The Central Vigilance Commission has asked IIMA to come up with India's first index to measure perceptions of graft and corruption, based on the Corruption Perceptions Index of Transparency International. Key studies on state health indexes have also been released by IIMA, helping to highlight the progress made on the same by various states across the country.

Training
Through its Executive Education programs, IIMA will train key senior officers from Chhattisgarh, as well as state Chief Minister Raman Singh, focussing on key management practices and project management. Officers from the Delhi Jal Board will also undergo training on Project and Risk Management. A MoU has also been signed between the Institute and the Delhi Govt to train the principals of all 1024 schools run by it, with the training to be conducted by the RTE Resource Centre.

RTE-RC
The Right to Education Resource Centre (RTE-RC), started by a group of students under the guidance of Ankur Sarin, helps parents fill out forms and get children admitted under the RTE Act, while also raising awareness about the issue of underutilization of the Act. The centre received 1800 application in its first year of operation, raising the number of children admitted under RTE from 30 in 2013 to nearly 600 in 2014.

Prayaas
Launched in 2004, Prayaas impacts the lives underprivileged students by directly providing them a higher quality of education through specially appointed teachers, with classes running out of the New Campus, as also through funding drives that enable students to move to better schools, in a hope for better education and better lives. The IIMA community actively helps the children with their homework and preparation for examinations. Additionally, the children use the campus' facilities and participate in activities like painting, dance, crafts, etc.

SMILE
IIMA, in association with the Wagh Bakri Group, set up an initiative called SMILE (Student Mediated Initiative for Learning to Excel) to educate underprivileged kids wherein students will conduct classes in their free time. This has been piloted in a space provided by the Ahmedabad Municipal Corporation (AMC) under a flyover near the IIMA campus.

Notable alumni
Among BSE 500 CEOs with MBA, the highest proportion come from IIM Ahmedabad. IIM-A alumni have garnered 9 Padma Awards – 4 Padma Bhushan awards (K. V. Kamath, CK Prahalad, Mallika Sarabhai and M. S. Banga) and 5 Padma Shri awards (Kiran Karnik, Kailasam Raghavendra Rao, S. P. Kothari, Sanjeev Bikhchandani, and Srikant Datar). Other notable alumni are Acharya Prashant, Raghuram Rajan, Arvind Subramanian, Harsha Bhogle, Ajay Banga, Rashmi Bansal, Chetan Bhagat, Ivan Menezes, Deep Kalra, Shikha Sharma, and Gopi Rathod.

Notable faculty
Past and present faculty at IIM Ahmedabad include three former Governors of the Reserve Bank of India – C. Rangarajan (1968–1982), former Director I. G. Patel (1996–2001), and Y. Venugopal Reddy (current Professor of Practice). Other notable faculty over the years have been:

 * C. K. Prahalad, famous management thinker, exponent of Core competency and Fortune at the Bottom of the Pyramid
 * Ravi J. Matthai, first full-time Director, management educationist noted for establishing Institute of Rural Management Anand
 * Bakul Harshadrai Dholakia, Padma Shri awardee, Director (2002–2007)
 * Samuel Paul, Padma Shri awardee, IIMA's second director (1972–78)
 * Ravindra Dholakia, member, Monetary Policy Committee (India), 2016-20
 * Jayanth R Varma, member, Monetary Policy Committee (India), 2020-2024
 * Vijay Govindarajan, a New York Times & Wall Street Journal best-selling author, Thinkers50 Hall of Fame 2019 & Coxe Distinguished Professor, Tuck School of Business
 * Anil Kumar Gupta was a professor who was awarded Padma Shri for his contributions to management education.
 * Pankaj Chandra, former Director, Indian Institute of Management Bangalore and current Vice Chancellor, Ahmedabad University
 * G. Raghuram, Director, Indian Institute of Management Bangalore
 * Dheeraj Sharma, Director, Indian Institute of Management Rohtak
 * Shekhar Chaudhuri, former Director, Indian Institute of Management Calcutta
 * Abhishek Mishra was a faculty member for six years, before leaving to become a member of Samajwadi Party and an elected MLA of Uttar Pradesh.
 * Jahar Saha, Institute Director 1998–2002
 * Rajnish Rai
 * Tarun Jain, Mahalanobis Memorial Medalist, 2020

Other notable faculty include prominent scholars such as Marti G. Subrahmanyam, Ashish Nanda, and T. V. Rao, among others.

Others
N. R. Narayana Murthy, an Indian tech industrialist and the co-founder of Infosys, got his first job as chief systems programmer at IIM Ahmedabad.

Endowment
The IIM Ahmedabad Endowment Fund is India's first endowment fund set up at a management school. The fund was established at IIM Ahmedabad in June 2020 from an initial corpus of ₹100 Crore provided by 10 founding alumni. The endowment aims to grow the fund to ₹1,000 Crore over the next five years.

The fund was launched by the Chairperson of IIM Ahmedabad Board of Governors, Kumar Mangalam Birla.

The initial corpus was contributed by 10 founding alumni from across batches. This includes Deep Kalra, Founder and Group CEO, MakeMyTrip, Sandeep Singhal and SK Jain, co-founders, WestBridge Capital, Sanjeev Bikhchandani, Founder & Executive Vice Chairman, Info Edge, Kavita Iyer, Trustee, SIFF, VT Bharadwaj, co-founder, A91 Partners, Ramesh Mangaleswaran, Senior Partner, McKinsey & Company, Meenakshi Ramesh, co-founder, Citizen Matters, Kuldeep Jain, founder, Cleanmax Enviro Energy Solutions, GV Ravishankar, MD, Sequoia Capital India, Arun Duggal, chairman, ICRA.

According to Ravishankar, MD, Sequoia Capital India, the plan for the fund is to invest in government securities.

The endowment fund will be managed by an independent Endowment Committee consisting of initial alumni contributors, and the Director, and Dean, Alumni and External Relations (AER) of IIM Ahmedabad. The purpose of the endowment is to "make a larger impact in the field of education, entrepreneurial leadership, management practice and public policy".

In popular culture
2 States (2014 film) a Bollywood film based on the eponymous novel by Chetan Bhagat, starring Alia Bhatt and Arjun Kapoor, was shot at the IIM-A campus. Prior to this, the 1974 Bollywood movie, Parinay had some scenes shot at the Heritage campus. The movie starred Shabana Azmi and Romesh Sharma in lead roles.


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Grating

A grating is any regularly spaced collection of essentially identical, parallel, elongated elements. Gratings usually consist of a single set of elongated elements, but can consist of two sets, in which case the second set is usually perpendicular to the first (as illustrated). When the two sets are perpendicular, this is also known as a grid (as in grid paper) or a mesh.

As filters
A grating covering a drain (as illustrated) can be a collection of iron bars (the identical, elongated elements) held together (to ensure the bars are parallel and regularly spaced) by a lighter iron frame. Gratings over drains and air vents are used as filters, to block movement of large solids (e.g. people) and to allow movement of liquids. A register is a type of grating used in heating, ventilation, and air conditioning, which transmits air, while stopping solid objects.

As decking
Grating can also come in panels that are often used for decks on bridges, footbridges and catwalks. Grating can be made of materials such as steel, aluminum, fiberglass. Fiberglass grating is also known as FRP grating. They are used to optimize bending stiffness while minimizing weight.

Optical grating

As optical elements, optical gratings are images having the characteristic pattern of alternating, parallel lines. The lines alternate between high and low reflectance (black-white gratings) or high and low transmittance (transparent-opaque gratings). The grating profile is the function of the reflectance or transmittance perpendicular to the lines. This function is generally a square wave, in that every transition between lines is abrupt.

A grating can be defined by six parameters:
 * Spatial frequency is the number of cycles occupying a particular distance (e.g. 10 line pairs per millimeter). The period of the grating is the inverse of the spatial frequency, measured in distance (e.g. 0.1 mm).
 * Duty Cycle is the relative thickness of high and low lines. The duty cycle is the ratio of the width of the low line (black or opaque) to one whole grating period.
 * Profile is the shape of the repeating pattern, which is typically a square wave but can also be any periodic pattern (sine wave, triangle wave, sawtooth wave, etc.).
 * Contrast is a measure of the difference in luminance between the high lines of the grating and the low lines. It is usually expressed as Michelson contrast: the difference between maximum and minimum luminance divided their sum.
 * Orientation is the angle the grating makes with some reference orientation (such as the y-axis in a picture or of another grating). It is usually measured in degree or in radians.
 * Phase is the position of the grating profile relative to some reference position. It is usually measured in degrees (from 0 to 360 for one complete cycle) or in radians (2π for one complete cycle). For example, two identical transparent gratings of 50% duty cycle and the same orientation will appear fully opaque only if the relative phase is π (180 degrees).

Gratings with sine wave profiles are used extensively in optics to determine the transfer functions of lenses. A lens will form an image of a sine wave grating that is still sinusoidal, but with some reduction in its contrast depending on the spatial frequency and possibly some change in phase. The branch of mathematics dealing with this part of optics is Fourier analysis while the associated branch of study is Fourier optics. Gratings are also used extensively in research into visual perception. Campbell and Robson promoted using sine-wave gratings by arguing that the human visual performs a Fourier analysis on retinal images.

Diffraction gratings
Grating can also refer to a diffraction grating: a reflecting or transparent optical component on which there are many fine, parallel, equally spaced grooves. They disperse light, so are one of the main functional components in many kinds of spectrometers, which decompose a light source into its constituent wavelength components.

title: Grating


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Chondrite

A chondrite is a stony (non-metallic) meteorite that has not been modified, by either melting or differentiation of the parent body. They are formed when various types of dust and small grains in the early Solar System accreted to form primitive asteroids. Some such bodies that are captured in the planet's gravity well become the most common type of meteorite by arriving on a trajectory toward the planet's surface. Estimates for their contribution to the total meteorite population vary between 85.7% and 86.2%.

Their study provides important clues for understanding the origin and age of the Solar System, the synthesis of organic compounds, the origin of life and the presence of water on Earth. One of their characteristics is the presence of chondrules (from the Ancient Greek χόνδρος chondros, grain), which are round grains formed in space as molten or partially molten droplets of distinct minerals. Chondrules typically constitute between 20% and 80% of a chondrite by volume.

Chondrites can be distinguished from iron meteorites by their low iron and nickel content. Non-metallic meteorites that lack chondrules are achondrites, which are believed to have formed more recently than chondrites. There are currently over 27,000 chondrites in the world's collections. The largest individual stone ever recovered, weighing 1770 kg, was part of the Jilin meteorite shower of 1976. Chondrite falls range from single stones to extraordinary showers consisting of thousands of individual stones. An instance of the latter occurred in the Holbrook fall of 1912, in which an estimated 14,000 stones grounded in northern Arizona.

Origin and history
Chondrites were formed by the accretion of particles of dust and grit present in the primitive Solar System which gave rise to asteroids over 4.54 billion years ago. These asteroid parent bodies of chondrites are (or were) small to medium-sized asteroids that were never part of any body large enough to undergo melting and planetary differentiation. Dating using 206Pb/204Pb gives an estimated age of 4,566.6 ± 1.0 Ma, matching ages for other chronometers. Another indication of their age is the fact that the abundance of non-volatile elements in chondrites is similar to that found in the atmosphere of the Sun and other stars in our galaxy.

Although chondritic asteroids never became hot enough to melt based upon internal temperatures, many of them reached high enough temperatures that they experienced significant thermal metamorphism in their interiors. The source of the heat was most likely energy coming from the decay of short-lived radioisotopes (half-lives less than a few million years) that were present in the newly formed Solar System, especially 26Al and 60Fe, although heating may have been caused by impacts onto the asteroids as well. Many chondritic asteroids also contained significant amounts of water, possibly due to the accretion of ice along with rocky material.

As a result, many chondrites contain hydrous minerals, such as clays, that formed when the water interacted with the rock on the asteroid in a process known as aqueous alteration. In addition, all chondritic asteroids were affected by impact and shock processes due to collisions with other asteroids. These events caused a variety of effects, ranging from simple compaction to brecciation, veining, localized melting, and formation of high-pressure minerals. The net result of these secondary thermal, aqueous, and shock processes is that only a few known chondrites preserve in pristine form the original dust, chondrules, and inclusions from which they formed.

Characteristics
Prominent among the components present in chondrites are the enigmatic chondrules, millimetre-sized spherical objects that originated as freely floating, molten or partially molten droplets in space; most chondrules are rich in the silicate minerals olivine and pyroxene.

Chondrites also contain refractory inclusions (including Ca–Al inclusions), which are among the oldest objects to form in the Solar System, particles rich in metallic Fe-Ni and sulfides, and isolated grains of silicate minerals. The remainder of chondrites consists of fine-grained (micrometre-sized or smaller) dust, which may either be present as the matrix of the rock or may form rims or mantles around individual chondrules and refractory inclusions. Embedded in this dust are presolar grains, which predate the formation of our solar system and originated elsewhere in the galaxy. The chondrules have distinct texture, composition and mineralogy, and their origin continues to be the object of some debate. The scientific community generally accepts that these spheres were formed by the action of a shock wave that passed through the Solar System, although there is little agreement as to the cause of this shock wave.

An article published in 2005 proposed that the gravitational instability of the gaseous disk that formed Jupiter generated a shock wave with a velocity of more than 10 km/s, which resulted in the formation of the chondrules.

Chondrite classification
Chondrites are divided into about 15 distinct groups (see Meteorites classification) on the basis of their mineralogy, bulk chemical composition, and oxygen isotope compositions (see below). The various chondrite groups likely originated on separate asteroids or groups of related asteroids. Each chondrite group has a distinctive mixture of chondrules, refractory inclusions, matrix (dust), and other components and a characteristic grain size. Other ways of classifying chondrites include weathering and shock.

Chondrites can also be categorized according to their petrologic type, which is the degree to which they were thermally metamorphosed or aqueously altered (they are assigned a number between 1 and 7). The chondrules in a chondrite that is assigned a "3" have not been altered. Larger numbers indicate an increase in thermal metamorphosis up to a maximum of 7, where the chondrules have been destroyed. Numbers lower than 3 are given to chondrites whose chondrules have been changed by the presence of water, down to 1, where the chondrules have been obliterated by this alteration.

A synthesis of the various classification schemes is provided in the table below.

Enstatite chondrites

Enstatite chondrites (also known as E-type chondrites) are a rare form of meteorite thought to comprise only about 2% of the chondrites that fall to Earth. Only about 200 E-Type chondrites are currently known. The majority of enstatite chondrites have either been recovered in Antarctica or have been collected by the American National Weather Association. They tend to be high in the mineral enstatite (MgSiO3), from which they derive their name.

E-type chondrites are among the most chemically reduced rocks known, with most of their iron taking the form of metal or sulfide rather than as an oxide. This suggests that they were formed in an area that lacked oxygen, probably within the orbit of Mercury.

Ordinary chondrites
Ordinary chondrites are by far the most common type of meteorite to fall to Earth: about 80% of all meteorites and over 90% of chondrites are ordinary chondrites. They contain abundant chondrules, sparse matrix (10–15% of the rock), few refractory inclusions, and variable amounts of Fe–Ni metal and troilite (FeS). Their chondrules are generally in the range of 0.5 to 1 mm in diameter. Ordinary chondrites are distinguished chemically by their depletions in refractory lithophile elements, such as Ca, Al, Ti, and rare earths, relative to Si, and isotopically by their unusually high 17O/16O ratios relative to 18O/16O compared to Earth rocks.

Most, but not all, ordinary chondrites have experienced significant degrees of metamorphism, having reached temperatures well above 500 °C on the parent asteroids. They are divided into three groups, which have different amounts of metal and different amounts of total iron:
 * H chondrite have high total iron and high metallic Fe (15–20% Fe–Ni metal by mass ), and smaller chondrules than L and LL chondrites. They are formed of bronzite, olivine, pyroxene, plagioclase, metals and sulfides and ~42% of ordinary chondrite falls belong to this group (see Meteorite fall statistics).
 * L chondrites have low total iron contents (including 7–11% Fe–Ni metal by mass). ~46% of ordinary chondrite falls belong to this group, which makes them the most common type of meteorite to fall on Earth.
 * LL chondrites have low total iron and low metal contents (3–5% Fe–Ni metal by mass of which 2% is metallic Fe and they also contain bronzite, oligoclase and olivine). Only 1 in 10 ordinary chondrite falls belong to this group.

An example of this group is the NWA 869 meteorite.

Carbonaceous chondrites
Carbonaceous chondrites (also known as C-type chondrites) make up less than 5% of the chondrites that fall on Earth. They are characterized by the presence of carbon compounds, including amino acids. They are thought to have been formed the farthest from the sun of any of the chondrites as they have the highest proportion of volatile compounds. Another of their main characteristics is the presence of water or of minerals that have been altered by the presence of water.

There are many groups of carbonaceous chondrites, but most of them are distinguished chemically by enrichments in refractory lithophile elements relative to Si and isotopically by unusually low ratios of 17O/16O relative to 18O/16O, when compared to Earth rocks. All groups of carbonaceous chondrites except the CH group are named for a characteristic type specimen:
 * CI (Ivuna type) chondrites entirely lack chondrules and refractory inclusions; they are composed almost exclusively of fine-grained material that has experienced a high degree of aqueous alteration on the parent asteroid. CI chondrites are highly oxidized, brecciated rocks, containing abundant magnetite and sulfate minerals, and lacking metallic Fe. It is a matter of some controversy whether they once had chondrules and refractory inclusions that were later destroyed during formation of hydrous minerals, or they never had chondrules in the first place. CI chondrites are notable because their chemical compositions closely resemble that of the solar photosphere, neglecting the hydrogen and helium. Thus, they have the most "primitive" compositions of any meteorites and are often used as a standard for assessing the degree of chemical fractionation experienced by materials formed throughout the Solar System.
 * CO (Ornans type) and CM (Mighei type) chondrites are two related groups that contain very small chondrules, mostly 0.1 to 0.3 mm in diameter; refractory inclusions are quite abundant and have similar sizes to chondrules.

 * CM chondrites are composed of about 70% fine-grained material (matrix), and most have experienced extensive aqueous alteration. The much studied Murchison meteorite, which fell in Australia in 1969, is the best-known member of this group.
 * CO chondrites have only about 30% matrix and have experienced very little aqueous alteration. Most have experienced small degrees of thermal metamorphism.
 * CR (Renazzo type), CB (Bencubbin type), and CH (high metal) carbonaceous chondrites are three groups that seem to be related by their chemical and oxygen isotopic compositions. All are rich in metallic Fe–Ni, with CH and especially CB chondrites having a higher proportion of metal than all other chondrite groups. Although CR chondrites are clearly similar in most ways to other chondrite groups, the origins of CH and CB chondrites are somewhat controversial. Some workers conclude that many of the chondrules and metal grains in these chondrites may have formed by impact processes after "normal" chondrules had already formed, and thus they may not be "true" chondrites.

 * CR chondrites have chondrules that are similar in size to those in ordinary chondrites (near 1 mm), few refractory inclusions, and matrix comprises nearly half the rock. Many CR chondrites have experienced extensive aqueous alteration, but some have mostly escaped this process.
 * CH chondrites are remarkable for their very tiny chondrules, typically only about 0.02 mm (20 micrometres) in diameter. They have a small proportion of equally tiny refractory inclusions. Dusty material occurs as discrete clasts, rather than as a true matrix. CH chondrites are also distinguished by extreme depletions in volatile elements.
 * CB chondrites occur in two types, both of which are similar to CH chondrites in that they are very depleted in volatile elements and rich in metal. CBa (subgroup a) chondrites are coarse grained, with large, often cm-sized chondrules and metal grains and almost no refractory inclusions. Chondrules have unusual textures compared to most other chondrites. As in CH chondrites, dusty material only occurs in discrete clasts, and there is no fine-grained matrix. CBb (subgroup b) chondrites contain much smaller (mm-sized) chondrules and do contain refractory inclusions.
 * CV (Vigarano type) chondrites are characterized by mm-sized chondrules and abundant refractory inclusions set in a dark matrix that comprises about half the rock. CV chondrites are noted for spectacular refractory inclusions, some of which reach centimetre sizes, and they are the only group to contain a distinctive type of large, once-molten inclusions. Chemically, CV chondrites have the highest abundances of refractory lithophile elements of any chondrite group. The CV group includes the remarkable Allende fall in Mexico in 1969, which became one of the most widely distributed and, certainly, the best-studied meteorite in history.
 * CK (Karoonda type) chondrites are chemically and texturally similar to CV chondrites. However, they contain far fewer refractory inclusions than CV, they are much more oxidized rocks, and most of them have experienced considerable amounts of thermal metamorphism (compared to CV and all other groups of carbonaceous chondrites).
 * CL (Loongana type) chondrites are largely chondrules and CAIs, correspondingly low in matrix and volatiles, with trace elements resembling CR. Triple oxygen position near the CV-CK area.
 * Ungrouped carbonaceous chondrites: A number of chondrites are clearly members of the carbonaceous chondrite class, but do not fit into any of the groups. These include: the Tagish Lake meteorite, which fell in Canada in 2000 and is intermediate between CI and CM chondrites; and Acfer 094, an extremely primitive chondrite that shares properties with both CM and CO groups.

Kakangari chondrites
Three chondrites form what is known as the K (Kakangari type) grouplet: Kakangari, LEW 87232, and Lea Co. 002. They are characterized by large amounts of dusty matrix and oxygen isotope compositions similar to carbonaceous chondrites, highly reduced mineral compositions and high metal abundances (6% to 10% by volume) that are most like enstatite chondrites, and concentrations of refractory lithophile elements that are most like ordinary chondrites.

Many of their other characteristics are similar to the O, E and C chondrites.

Rumuruti chondrites
Rumuruti (R) type chondrites are a very rare group, with only one documented fall out of almost 900 documented chondrite falls. They have a number of properties in common with ordinary chondrites, including similar types of chondrules, few refractory inclusions, similar chemical composition for most elements, and the fact that 17O/16O ratios are anomalously high compared to Earth rocks. However, there are significant differences between R chondrites and ordinary chondrites: R chondrites have much more dusty matrix material (about 50% of the rock); they are much more oxidized, containing little metallic Fe–Ni; and their enrichments in 17O are higher than those of ordinary chondrites. Nearly all the metal they contain is oxidized or in the form of sulfides. They contain fewer chondrules than the E chondrites and appear to come from an asteroid's regolith.

Composition
Because chondrites accumulated from material that formed very early in the history of the Solar System, and because chondritic asteroids did not melt, they have very primitive compositions. "Primitive," in this sense, means that the abundances of most chemical elements do not differ greatly from those that are measured by spectroscopic methods in the photosphere of the sun, which in turn should be well-representative of the entire Solar System (note: to make such a comparison between a gaseous object like the sun and a rock like a chondrite, scientists choose one rock-forming element, such as silicon (Si), to use as a reference point, and then compare ratios. Thus, the atomic ratio of Mg/Si measured in the sun (1.07) is identical to that measured in CI chondrites ).

Although all chondrite compositions can be considered primitive, there is variation among the different groups, as discussed above. CI chondrites seem to be nearly identical in composition to the sun for all but the gas-forming elements (e.g., hydrogen (H), carbon (C), nitrogen (N), and noble gases: helium (He), neon (Ne), argon (Ar) etc.). Other chondrite groups deviate from the solar composition (i.e., they are fractionated) in highly systematic ways:
 * At some point during the formation of many chondrites, particles of metal became partially separated from particles of silicate minerals. As a result, chondrites coming from asteroids that did not accrete with their full complement of metal (e.g., L, LL, and EL chondrites) are depleted in all siderophile elements, whereas those that accreted too much metal (e.g., CH, CB, and EH chondrites) are enriched in these elements compared to the sun.
 * In a similar manner, although the exact process is not very well understood, highly refractory elements like Ca and Al became separated from less refractory elements like Mg and Si, and were not uniformly sampled by each asteroid. The parent bodies of many groups of carbonaceous chondrites contain over-sampled grains rich in refractory elements, whereas those of ordinary and enstatite chondrites were deficient in them.
 * No chondrites except the CI group formed with a full, solar complement of volatile elements. In general, the level of depletion corresponds to the degree of volatility, where the most volatile elements are most depleted.

Petrologic types
A chondrite's group is determined by its primary chemical, mineralogical, and isotopic characteristics (above). The degree to which it has been affected by the secondary processes of thermal metamorphism and aqueous alteration on the parent asteroid is indicated by its petrologic type, which appears as a number following the group name (e.g., an LL5 chondrite belongs to the LL group and has a petrologic type of 5). The current scheme for describing petrologic types was devised by Van Schmus and Wood in 1967.

The petrologic-type scheme originated by Van Schmus and Wood is really two separate schemes, one describing aqueous alteration (types 1–2) and one describing thermal metamorphism (types 3–6). The aqueous alteration part of the system works as follows:

 * Type 1 was originally used to designate chondrites that lacked chondrules and contained large amounts of water and carbon. Current usage of type 1 is simply to indicate meteorites that have experienced extensive aqueous alteration, to the point that most of their olivine and pyroxene have been altered to hydrous phases. This alteration took place at temperatures of 50 to 150 °C, so type 1 chondrites were warm, but not hot enough to experience thermal metamorphism. The members of the CI group, plus a few highly altered carbonaceous chondrites of other groups, are the only instances of type 1 chondrites.
 * Type 2 chondrites are those that have experienced extensive aqueous alteration, but still contain recognizable chondrules as well as primary, unaltered olivine and/or pyroxene. The fine-grained matrix is generally fully hydrated and minerals inside chondrules may show variable degrees of hydration. This alteration probably occurred at temperatures below 20 °C, and again, these meteorites are not thermally metamorphosed. Almost all CM and CR chondrites are petrologic type 2; with the exception of some ungrouped carbonaceous chondrites, no other chondrites are type 2.

The thermal metamorphism part of the scheme describes a continuous sequence of changes to mineralogy and texture that accompany increasing metamorphic temperatures. These chondrites show little evidence of the effects of aqueous alteration:

 * Type 3 chondrites show low degrees of metamorphism. They are often referred to as unequilibrated chondrites because minerals such as olivine and pyroxene show a wide range of compositions, reflecting formation under a wide variety of conditions in the solar nebula. (Type 1 and 2 chondrites are also unequilibrated.) Chondrites that remain in nearly pristine condition, with all components (chondrules, matrix, etc.) having nearly the same composition and mineralogy as when they accreted to the parent asteroid, are designated type 3.0. As petrologic type increases from type 3.1 through 3.9, profound mineralogical changes occur, starting in the dusty matrix, and then increasingly affecting the coarser-grained components like chondrules. Type 3.9 chondrites still look superficially unchanged because chondrules retain their original appearances, but all of the minerals have been affected, mostly due to diffusion of elements between grains of different composition.
 * Types 4, 5, and 6 chondrites have been increasingly altered by thermal metamorphism. These are equilibrated chondrites, in which the compositions of most minerals have become quite homogeneous due to high temperatures. By type 4, the matrix has thoroughly recrystallized and coarsened in grain size. By type 5, chondrules begin to become indistinct and matrix cannot be discerned. In type 6 chondrites, chondrules begin to integrate with what was once matrix, and small chondrules may no longer be recognizable. As metamorphism proceeds, many minerals coarsen and new, metamorphic minerals such as feldspar form.

Some workers have extended the Van Schmus and Wood metamorphic scheme to include a type 7, although there is not consensus on whether this is necessary. Type 7 chondrites have experienced the highest temperatures possible, short of that required to produce melting. Should the onset of melting occur the meteorite would probably be classified as a primitive achondrite instead of a chondrite.

All groups of ordinary and enstatite chondrites, as well as R and CK chondrites, show the complete metamorphic range from type 3 to 6. CO chondrites comprise only type 3 members, although these span a range of petrologic types from 3.0 to 3.8.

Presence of water
These meteorites either contain a proportion of water or minerals that have been altered by water. This suggests that the asteroid from which these meteorites originate must have contained water. At the beginning of the Solar System this would have been present as ice and a few million years after the asteroid formed the ice would have melted allowing the liquid water to react with and alter the olivines and pyroxenes. The formation of rivers and lakes on the asteroid is thought to have been unlikely if it was sufficiently porous to allow the water to percolate towards its interior, as occurs in terrestrial aquifers.

It is thought possible that a proportion of the water present on the Earth comes from the impact of comets and carbonaceous chondrites with the Earth's surface.

Origin of life

Carbonaceous chondrites contain more than 600 organic compounds that were synthesized in distinct places and at distinct times. These organic compounds include: hydrocarbons, carboxylic acids, alcohols, ketones, aldehydes, amines, amides, sulfonic acids, phosphonic acids, amino acids, nitrogenous bases, etc. These compounds can be divided into three main groups: a fraction that is not soluble in chloroform or methanol, chloroform soluble hydrocarbons and a fraction that is soluble in methanol (which includes the amino acids).

The first fraction appears to originate from interstellar space and the compounds belonging to the other fractions derive from a planetoid. It has been proposed that the amino acids were synthesized close to the surface of a planetoid by the radiolysis (dissociation of molecules caused by radiation) of hydrocarbons and ammonium carbonate in the presence of liquid water. In addition, the hydrocarbons could have formed deep within a planetoid by a process similar to the Fischer–Tropsch process. These conditions could be analogous to the events that caused the origin of life on Earth.

The Murchison meteorite has been thoroughly studied; it fell in Australia close to the town that bears its name on 28 September 1969. It is a CM2 and it contains common amino acids such as glycine, alanine and glutamic acid as well as other less common ones such as isovaline and pseudo-leucine.

Two meteorites that were collected in Antarctica in 1992 and 1995 were found to be abundant in amino acids, which are present at concentrations of 180 and 249 ppm (carbonaceous chondrites normally contain concentrations of 15 ppm or less). This could indicate that organic material is more abundant in the Solar System than was previously believed, and it reinforces the idea that the organic compounds present in the primordial soup could have had an extraterrestrial origin.

title: Chondrite


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International Amateur Radio Union

The International Amateur Radio Union (IARU) is an international confederation of national organisations that allows a forum for common matters of concern to amateur radio operators worldwide, and collectively represents matters to the International Telecommunication Union (ITU). The International Amateur Radio Union was founded in 1925 and, as of July 2021, it is composed of 172 national member societies.

History
Following an informal meeting in 1924 of representatives from France, Great Britain, Belgium, Switzerland, Italy, Spain, Luxembourg, Canada, and the United States, a plan was formulated to hold an International Amateur Congress in Paris, France, in April 1925. This Congress was held for the purpose of founding an international amateur radio organization. The Congress was attended by representatives of 23 countries in Europe, Americas, and Asia. A constitution for the IARU was adopted on April 17, and the formation of the International Amateur Radio Union was ratified on April 18, 1925. In the current era, this is the date (April 18) on which World Amateur Radio Day is celebrated. The protocol of the congress was written in English, French and Esperanto.

Governance
The IARU has an elected President and Vice President, an appointed Secretary and other officials (including regional representatives) forming an Administrative Council. These office holders are presently Timothy Ellam, VE6SH (Canada), President; Ole Garpestad, LA2RR (Norway), Vice-President; and Joel Harrison, W5ZN (United States), Secretary. The IARU International Secretariat (IARUIS) is operated by a member society after election by members. Currently, the American Radio Relay League (ARRL) operates the IARUIS from its headquarters in Newington, Connecticut, US.

Regional organisation
The IARU is organised into three regions, named Region 1, Region 2, and Region 3. These regions correspond to the regulatory regions used by the International Telecommunication Union. Each region has an Executive Committee, typically composed of a President, Vice-President, Secretary, Treasurer, and several Directors. These regional officers are elected by representatives from the member societies at triennial regional conferences. Coordinators may be appointed by the Executive Committee of their region to support particular areas within the region, or to promote certain amateur radio activities within the region. All three regions have appointed Coordinators for Amateur Radio Direction Finding, emergency communications, monitoring for electromagnetic interference, and radio propagation.

IARU Region 1
IARU Region 1 includes the member societies representing amateur radio operators in Africa, Europe, the Middle East, and northern Asia. IARU Region 1 has the largest number of member societies among the three IARU regions, and has been the source of several international initiatives. IARU Region 1 lobbying efforts led to the creation of the 30 meter, 17 meter, and 12 meter amateur radio bands, improving the standardization of reciprocal licensing, promoting Amateur Radio Direction Finding and initiating youth related activities, known as "the Youngsters On the Air project" (YOTA)

Executive officers:
 * President: 🇫🇷 Sylvain Azarian, F4GKR
 * Vice-President: 🇱🇧 Hani Raad, OD5TE
 * Secretary: 🇸🇪 Mats Espling, SM6EAN
 * Treasurer: 🇨🇭 Andreas Thiemann, HB9JOE

IARU Region 2
IARU Region 2 includes the member societies representing amateur radio operators in the Americas. The organization of IARU Region 2 was founded in 1964 when representatives from 15 national radio societies attended the First Panamerican Radio Amateur Congress in Mexico City, Mexico. Antonio Pita, XE1CCP was the region's first elected president.

Executive officers:
 * President: 🇲🇽 Ramón Santoyo, XE1KK
 * Vice-President: 🇸🇻 José Arturo Molina, YS1MS
 * Secretary: 🇨🇦 George Gorsline, VE3YV
 * Treasurer: 🇺🇸 John Bellows, K0QB

IARU Region 3
IARU Region 3 includes the member societies representing amateur radio operators in Australia, most of Asia, and the Pacific Islands. Although most of their membership is located in other IARU regions, the American Radio Relay League and the Radio Society of Great Britain are full member societies of IARU Region 3. The ARRL represents amateur radio operators in American Samoa, Guam, the Northern Marianas, and other dependent territories in the Pacific Ocean. The RSGB represents amateur radio operators in the British Indian Ocean Territory. IARU Region 3 has a special emphasis on promoting the harmonization of license qualifications in an effort to promote easier reciprocal operations by amateur radio operators in the region.

Executive officers:
 * President: 🇮🇩 Wisnu Widjaja, YB0AZ
 * Secretary: 🇯🇵 Shizuo Endo, JE1MUI

Countries without IARU member societies
* = Amateur radio licenses not issued in this country

GAREC - Global Amateur Radio Emergency Communications Conferences
The Global Amateur Radio Emergency Communications Conference or "GAREC" is a yearly conference held by the International Amateur Radio Union for discussion of amateur radio operation during natural disasters and other emergencies with the motto, "Saving lives through emergency communications". GAREC was first held in Tampere, Finland in 2005, coinciding with the adoption of the Tampere Convention, a globally binding emergency communications treaty that had been signed in Tampere in 1998. In later conferences, the venue has attempted to rotate in sequence through ITU Regions 1, 2 and 3 (though not necessarily in that particular order).

Radiosport
The IARU organises and promotes radiosport activities throughout the world. The IARU promulgates the rules used for high-speed telegraphy and sponsors regional and world championships. The IARU also promulgates the rules used by most competitions in amateur radio direction finding, including IARU-sponsored regional and world championships. The IARU also sponsors the annual IARU HF World Championship in amateur radio contesting. The IARU does not directly administer any of these radiosport events, but authorises and sponsors them through host organisations.

Operating Station and the WAC Award
The IARU maintains a radio station at its headquarters in Newington, Connecticut. Its callsign is NU1AW. As an amateur radio station licensed by the U.S. Federal Communications Commission the "1" stands for its location in the New England area. "NU" was taken from the pre-1928 era when amateurs made up their own prefixes, and informally used these letters to show they were in "North America—USA". The "AW" suffix represents the connection with the American Radio Relay League, whose own station is W1AW. NU1AW is frequently active during amateur radio contests.

For many years the IARU has issued the Worked All Continents certificate to amateurs who contact fellow hams in the six permanently populated continental areas of the world. Special awards and endorsements for various bands and modes are also available.

title: International Amateur Radio Union


text:
Bolshoi Theatre

The Bolshoi Theatre (Большо́й теа́тр) is a historic opera house in Moscow, Russia, originally designed by architect Joseph Bové. Before the October Revolution it was a part of the Imperial Theatres of the Russian Empire along with Maly Theatre (Small Theatre) in Moscow and a few theatres in Saint Petersburg (Hermitage Theatre, Bolshoi (Kamenny) Theatre, later Mariinsky Theatre and others).

The Bolshoi Ballet and Bolshoi Opera are among the oldest and best known ballet and opera companies in the world. It is by far the world's biggest ballet company, with more than 200 dancers. The theatre is the parent company of The Bolshoi Ballet Academy, a leading school of ballet. It has a branch at the Bolshoi Theater School in Joinville, Brazil.

The main building of the theatre, rebuilt and renovated several times during its history, is a landmark of Moscow and Russia (its iconic neoclassical façade is depicted on the Russian 100-ruble banknote). On 28 October 2011, the Bolshoi re-opened after an extensive six-year renovation. The official cost of the renovation is 21 billion rubles ($688 million). However, other Russian authorities and other people connected to it claimed much more public money was spent. The renovation included restoring acoustics to the original quality (which had been lost during the Soviet Era), as well as restoring the original Imperial decor of the Bolshoi.

Presently Bolshoi Theatre is under US and EU sanctions and banned from performing in these countries.

Origins
The company was founded on 28 March 1776, when Catherine II granted Prince Peter Urusov a licence to organise theatrical performances, balls and other forms of entertainment. Urusov set up the theatre in collaboration with English tightrope walker Michael Maddox. Initially, it held performances in a private home, but it acquired the Petrovka Theatre and on 30 December 1780, it began producing plays and operas, thus establishing what would become the Bolshoi Theatre. Fire destroyed the Petrovka Theatre on 8 October 1805, and the New Arbat Imperial Theatre replaced it on 13 April 1808, however it also succumbed to fire during the French invasion of Moscow in 1812.

The first instance of the theatre was built between 1821 and 1824, designed and supervised to completion by architect Joseph Bové based upon an initial competition-winning design created by Petersburg-based Russian architect Andrei Mikhailov that was deemed too costly to complete. The new building opened on 18 January 1825 as the Bolshoi Petrovsky Theatre with a performance of the catalan Fernando Sor's ballet, Cendrillon. Initially, it presented only Russian works, but foreign composers entered the repertoire around 1840.

Renovations in the 19th century
In 1843 a large-scale reconstruction of the theatre took place using a design by A. Nikitin, but a fire in 1853 caused extensive damage and so a further reconstruction was carried out, by Alberto Cavos, son of the opera composer Catterino Cavos.

20th century
On 7 December 1919 the house was renamed the State Academic Bolshoi Theatre. Only a few days later, however, on 12 December, there was an unsuccessful attempt to shut the institution entirely. Beethoven Hall opened on 18 February 1921. Ivan Rerberg directed further reconstruction of the theatre between 1921 and 1923. A bomb damaged the structure during World War II, but this was repaired.

New stage of 2002
A new stage for the Bolshoi Theatre, called the New Stage, went into service on 29 November 2002, constructed to the left of the theatre's historic main stage. Together with auxiliary buildings — a restored 17th-century building, two rehearsal halls, and artists' recreation rooms — it forms a single theatre complex, the Bolshoi Theatre of Russia. The new building is on a natural hill which it shared, until recently, blocks of old houses with communal apartments.

Major rebuilding and renovation (2005–2011)
From July 2005 to October 2011 the theatre was closed for restoration. The building, whose architecture combines three different styles, was damaged and a quick renovation seemed to be necessary.

Repairs were initially estimated at 15 billion rubles ($610 million) but engineers found that more than 75% of the structure was unstable, According to The Moscow Times, the true cost may have been double that, and Der Spiegel quotes a figure of $1.1 billion. The rebuilding and renovation was funded entirely by the federal government.

During the long period of reconstruction, the company continued to mount productions, with performances held on the New Stage and on the stage of the Great Kremlin Palace.

The renovation included restoring acoustics to the original quality (which had been lost during the Soviet Era), as well as restoring the original Imperial decor of the Bolshoi. After the renovation, the theater has a maximum capacity of 1,740 seats. Finally, on 28 October 2011, the Bolshoi Theatre re-opened with a concert featuring international artists and the ballet and opera companies. The first staged opera, Ruslan and Lyudmila, followed soon after.

Notable premieres
The Bolshoi has been the site of many historic premieres, including:
 * Tchaikovsky's The Voyevoda and Mazeppa
 * Modest Mussorgsky's one version of Boris Godunov was given on 16 December 1888.
 * Rachmaninoff's Aleko and Francesca da Rimini
 * Nikolai Rimsky-Korsakov's opera The Maid of Pskov, with Feodor Chaliapin singing the role of Ivan the Terrible
 * Dmitri Shostakovich's opera Lady Macbeth of the Mtsensk District in 1935.

Other notable facts

 * The first symphonic concert by the Bolshoi Orchestra took place at the Bolshoi Theatre on 4 May 1919, conducted by Serge Koussevitzky
 * During the COVID-19 pandemic, at least 34 members of the theatre were infected.

Ballet and opera
The Bolshoi is a repertory theatre, meaning that it draws from a list of productions, any one of which may be performed on a given evening. Since the dissolution of the Soviet Union, there have been a few attempts to reduce the theatre's traditional dependence on large state subsidies. The Bolshoi has been associated from its beginnings with ballet. Tchaikovsky's ballet Swan Lake premiered at the theatre on 4 March 1877. The chief ballet conductor from 1923 to 1963 was Yuri Fayer.

After the death of Joseph Stalin, the company toured internationally and became an important source of cultural prestige, as well as foreign currency earnings. As a result, the "Bolshoi Ballet" became a well-known name in the West.

However, the Bolshoi suffered from losses through a series of defections of its dancers. The first occurrence was on 23 August 1979, with Alexander Godunov; followed by Leonid Kozlov and Valentina Kozlova on 16 September 1979; and other cases in the following years. Bolshoi continues to tour regularly with opera and ballet productions in the post-Soviet era. Until the mid-1990s, most foreign operas were sung in Russian, but Italian and other languages have been heard more frequently on the Bolshoi stage in recent years.

Orchestra

Music director and chief conductor Vassily Sinaisky quit abruptly at the start of December 2013, after a 41-month tenure, citing the need to avoid conflict. General director Vladimir Urin accepted his resignation, and selected Tugan Sokhiev as replacement. Sokhiev's four-year contract, settled on 20 January 2014, and became effective immediately. Sokhiev left his position in connection with the 2022 Russian invasion of Ukraine. In December 2023, Valery Gergiev was appointed artistic director of the company, with immediate effect, with an initial contract of 5 years.

Chief conductors and music directors

 * Samuil Samosud (1936–1942)
 * Ariy Pazovsky (1943–1948)
 * Nikolai Golovanov (1948 –1953)
 * Alexander Melik-Pashayev (1953–1963)
 * Yevgeny Svetlanov (1963–1965)
 * Gennady Rozhdestvensky (1965–1970)
 * Yuri Simonov (1970–1985)
 * Alexander Lazarev (1987–1995)
 * Peter Feranec (1995–1998)
 * Mark Ermler (1998–2000)
 * Gennady Rozhdestvensky (2000–2001)
 * Alexander Vedernikov (2001–2009)
 * Leonid Desyatnikov (2009–2010)
 * Vassily Sinaisky (2010–2013)
 * Tugan Sokhiev (2014–2022)
 * Valery Gergiev (2023–present)

Cultural status
The Bolshoi Theatre attracts large numbers of tourists. As a result, prices can be much higher than in other Russian theatres.

Controversies

 * The rebuilding and renovation cost was $1.1 billion, sixteen times the initial estimate. In 2009 prosecutors alleged the lead contractor was paid three times for the same work.
 * Anastasia Volochkova, a former Bolshoi prima ballerina, has said she sees the theatre "as a big brothel" because, she has claimed, ballerinas are invited to parties by theatre administrators and refused roles if they do not accept.
 * On 17 January 2013, Sergei Filin, the Bolshoi's ballet director, was attacked with sulfuric acid and as a result lost much of his eyesight. A male dancer was later charged with the crime.
 * In the area of box office, a theatre insider told the German publication Der Spiegel that tickets are often sold to mafia dealers, who in turn sell them on the black market for double the face value.
 * Performance quality has been criticized by the former music director Alexander Vedernikov (2001-2009). He has claimed the Bolshoi Theatre was putting "bureaucratic interests before artistic ones."
 * July 8, 2017, three days before the premiere, the Bolshoi Theatre called off the premiere of a ballet about legendary dancer Rudolf Nureyev. The Director General Vladimir Urin claimed it was due to the bad quality of the dancing, however the principal dancer Maria Alexandrova claimed it was the first sign of a 'new era' of censorship. It was the first time a show has been pulled in such a way since the collapse of the Soviet Union (where such censorship persisted), sparking rumours about the motivation behind it.

title: Bolshoi Theatre


text:
User talk:Peter Ellis

Lisa vangreddig

For older talk, see User:Peter Ellis/Archive.

 * Removed full text of Welcome by Isomorphic 05:47, 17 Mar 2004 (UTC) (Peter Ellis 12:09, 27 Dec 2004 (UTC))
 * Some clean-up done.Peter Ellis 03:05, 24 May 2006 (UTC)

Hi Peter, thanks for your note at the New user log. Your interests are impressive! BTW, Wikipedia runs on MediaWiki; the developers would certainly be pleased if they were to read your praise of the software's usability. Anyway, welcome; I hope you enjoy contributing here, as I have. Chris Roy 22:28, 18 Mar 2004 (UTC)

Hi Peter, yes its me
Actually I saw your edit on one of the RAN related pages and meant to get in touch, but work has this habit of intruding!

We should catch up. My e-mail address is. @eds.com (gotta watch those e-mail address harvesters.

Nick Thorne

Commercial use of Image:Stan Grant snr.JPG
Re-licensed under cc-by-sa-2.5 attributable to John Rudder.

Anzac Day image
I was VERY pleased that this image 'lasted' for 4 years on such an important page (from the 90th Anzac Day, on 25 April 2005 until that day in 2009.)

+

James Cook
Hello there

I reverted your recent addition to this article because the vandalisation of the Cook statue is already covered in the article. Please also see the ongoing discussion on this very issue on the Talk page. Happy to discuss there. Aemilius Adolphin (talk) 00:43, 26 January 2024 (UTC)

Proposed deletion of K-line (x-ray)

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title: User talk:Peter Ellis


text:
Andy Merrill

Andy Merrill is an American voice actor best known for his portrayal of the character Brak on Space Ghost Coast to Coast, The Brak Show and Cartoon Planet; as well as Oglethorpe on Aqua Teen Hunger Force.

Space Ghost Coast to Coast
Merrill joined Cartoon Network within several months of its inception in 1992, coming over from sister company CNN. He started working in programming, and in 1993 he and then head of programming Mike Lazzo helped put together the first animated late-night talk show, Space Ghost Coast to Coast. He voiced Space Ghost in the first of two unaired pilots for the show.

In April 1994, Space Ghost Coast to Coast premiered on Cartoon Network. The concept was that 1960s Hanna-Barbera cartoon superhero Space Ghost had retired from being a superhero and was hosting his own talk show, in which he interviewed live action celebrity guests, with his old archenemies Zorak and Moltar as band leader and director. To date, the show has had over 90 episodes aired on television, and was one of the motivating forces behind the creation of the Adult Swim programming bracket started in 2001. Merrill helped produce and write for the show for years, and voiced "Council of Doom" members Brak and Lokar, who would appear on the show periodically, mostly Brak.

Merrill, along with Coast to Coast friend and co-star George Lowe, wrote on social media that their friend and co-star C. Martin Croker died on September 17, 2016. It was then revealed that Adult Swim would play the first produced episode of Space Ghost Coast to Coast aired 12:30 eastern, 11:30 central that night in honor of Croker's contribution not only to Space Ghost, but many Adult Swim shows in both animation and voice overs. The three of them, along with Dave Willis, Dana Snyder, and Carey Means had been friends since their earliest Cartoon Network days.

Cartoon Planet
In 1995, Cartoon Planet premiered on TBS (moving to Cartoon Network in 1996). Merrill wrote and produced the show, along with crew members who had worked on Space Ghost Coast to Coast, himself voicing the character of Brak. The main characters on Cartoon Planet were Space Ghost, Zorak, and Brak, and it was a show of skits and songs put together with the same limited animation used in Space Ghost Coast to Coast.

Originally, the skits and songs were filler for showing old cartoons owned by Turner Entertainment (Hanna-Barbera, Looney Tunes, Merrie Melodies, Popeye the Sailor) until the skits and songs became more popular and Brak developed more of a personality and grew popular with fans. The show eventually became entirely skits and songs.

Brak spin-offs
In 2000, two Sonny and Cher-style variety show specials premiered on Cartoon Network, titled Brak Presents the Brak Show Starring Brak. The show featured new animation, and new songs with celebrity guests and fellow Space Ghost villain Zorak. However, the specials were met with mixed reviews from fans. In the early hours of December 21, 2000, a new sitcom parody cartoon premiered, titled "Leave It to Brak", which was actually the pilot episode for the future Adult Swim show The Brak Show, which premiered on Adult Swim in 2001 and ran for three seasons.

Merill reprised Brak on the episode "Space Con" of the Max series Jellystone! which is also based on Hanna-Barbera characters.

Boomerang
Merrill left Atlanta briefly, moving to New Jersey for a year and joining the programming department of Boomerang, an asset of the Turner Broadcasting System.

title: Andy Merrill