text:
G-type main-sequence star

A G-type main-sequence star (spectral type: G-V), also often, and imprecisely, called a yellow dwarf, or G star, is a main-sequence star (luminosity class V) of spectral type G. Such a star has about 0.9 to 1.1 solar masses and an effective temperature between about 5300 and 6000 K. Like other main-sequence stars, a G-type main-sequence star converts the element hydrogen to helium in its core by means of nuclear fusion, but can also fuse helium when hydrogen runs out. The Sun, the star in the center of the Solar System to which the Earth is gravitationally bound, is an example of a G-type main-sequence star (G2V type). Each second, the Sun fuses approximately 600 million tons of hydrogen into helium in a process known as the proton–proton chain (4 hydrogens form 1 helium), converting about 4 million tons of matter to energy. Besides the Sun, other well-known examples of G-type main-sequence stars include Alpha Centauri, Tau Ceti, and 51 Pegasi.

Description
The term yellow dwarf is a misnomer, because G-type stars actually range in color from white, for more luminous types like the Sun, to only very slightly yellowish for less massive and luminous G-type main-sequence stars. The Sun is in fact white, but it can often appear yellow, orange or red through Earth's atmosphere due to atmospheric Rayleigh scattering, especially at sunrise and sunset. In addition, although the term "dwarf" is used to contrast G-type main-sequence stars with giant stars or bigger, stars similar to the Sun still outshine 90% of the stars in the Milky Way (which are largely much dimmer orange dwarfs, red dwarfs, and white dwarfs which are much more common, the latter being stellar remnants).

A G-type main-sequence star with the mass of the Sun will fuse hydrogen for approximately 10 billion years, until the hydrogen element is exhausted at the center of the star. When this happens, the star rapidly expands, cooling and darkening as it passes through the subgiant branch and ultimately expanding into many times its previous size at the tip of the red giant phase, about 1 billion years after leaving the main sequence. After this, the star's degenerate helium core abruptly ignites in a helium flash fusing helium, and the star passes on to the horizontal branch, and then to the asymptotic giant branch. Expanding even further as helium starts running out as it pulses violently, the star's gravity is not sufficient to hold its outer envelope, resulting in significant mass loss and shedding. The ejected material remains as a planetary nebula, radiating as it absorbs energetic photons from the photosphere. Eventually, the core begins to fade as nuclear reactions cease, and becomes a dense, compact white dwarf, which cools slowly from its high initial temperature as the nebula fades.

Spectral standard stars
The revised Yerkes Atlas system (Johnson & Morgan 1953) listed 11 G-type dwarf spectral standard stars; however, not all of these still exactly conform to this designation.

The "anchor points" of the MK spectral classification system among the G-type main-sequence dwarf stars, i.e. those standard stars that have remained unchanged over years, are Chara (G0V), the Sun (G2V), Kappa1 Ceti (G5V), 61 Ursae Majoris (G8V). Other primary MK standard stars include HD 115043 (G1V) and 16 Cygni B (G3V). The choices of G4 and G6 dwarf standards have changed slightly over the years among expert classifiers, but often-used examples include 70 Virginis (G4V) and 82 Eridani (G6V). There are not yet any generally agreed upon G7V and G9V standards.

Habitability
G-type main sequence stars can provide habitability for life to develop, such as the Sun with life on Earth. They also live long enough to give life enough time to develop, between 13 and 7.9 billion years. Our Sun lives about 10 billion years.

Planets
Besides the Sun and its planets, some of the nearest G-type stars known to have planets include 61 Virginis, HD 102365, HD 147513, Chalawan, Cervantes and Tau Ceti.

title: G-type main-sequence star


text:
Constitution of Russia

The Constitution of the Russian Federation (Конститу́ция Росси́йской Федера́ции) was adopted by national referendum on 12 December 1993. The last reform was in 2020, see 2020 amendments to the Constitution of Russia.

Russia's constitution came into force on 25 December 1993, at the moment of its official publication, and abolished the Soviet system of government. The current Constitution is the second most long-lived in the history of Russia, behind the Constitution of 1936. The text was drafted by the 1993 Constitutional Conference, which was attended by over 800 participants. Sergei Alexeyev, Sergey Shakhray, and sometimes Anatoly Sobchak are considered as the primary co-authors of the constitution. The text was inspired by Mikhail Speransky's constitutional project and the current French constitution. The USAID-funded lawyers also contributed to the development of the draft.

It replaced the previous Soviet-era Constitution of 12 April 1978, of the Russian Soviet Federative Socialist Republic (which had already been amended in April 1992 to reflect the dissolution of the Soviet Union and the sovereignty of the Russian Federation), following the 1993 Russian constitutional crisis.

Structure
The constitution is divided into two sections. Overall it creates a system of crown-presidentialism (see Partlett 2022 for details), which affords vast power to the office of the president to dominate executive, legislative, and judicial power.

Preamble
We, the multinational people of the Russian Federation, united by a common fate on our land, establishing human rights and freedoms, civic peace and accord, preserving the historically established state unity, proceeding from the universally recognized principles of equality and self-determination of peoples, revering the memory of ancestors who have conveyed to us the love for the Fatherland, belief in the good and justice, reviving the sovereign statehood of Russia and asserting the firmness of its democratic basic, striving to ensure the well-being and prosperity of Russia, proceeding from the responsibility for our Fatherland before the present and future generations, recognizing ourselves as part of the world community, adopt the Constitution of Russian Federation.

Section One

 * 1) The Fundamentals of the Constitutional System (Основы конституционного строя)
 * 2) Rights and Freedoms of Man and Citizen (Права и свободы человека и гражданина)
 * 3) The Federal Structure (Федеративное устройство)
 * 4) The President of the Russian Federation (Президент Российской Федерации)
 * 5) The Federal Assembly (Федеральное Собрание)
 * 6) The Government of the Russian Federation (Правительство Российской Федерации)
 * 7) Judicial Power and Procuracy (Судебная власть и прокуратура)
 * 8) Local Self-Government (Местное самоуправление)
 * 9) Constitutional Amendments and Review of the Constitution (Конституционные поправки и пересмотр Конституции)

Section Two

 * 1) Concluding and Transitional Provisions

Provisions
Especially on human rights and fundamental freedoms, the Constitution provides for human rights and freedoms of citizens according to the universally recognised principles and norms of international law as well as to their listing in the Constitution. (It affirms that the listing in the Constitution of the Russian Federation of the fundamental rights and freedoms shall not be interpreted as a rejection and derogation of other universally recognised human rights and freedoms.)

Executive

The Constitution of the Russian Federation specifies that the President is the Russian head of state, setting domestic and foreign policy and representing Russia both within the country and internationally [Article 80]. While the original constitution stipulated a four-year term and a maximum of two terms in succession, the current constitution decrees a six-year term. The four-year term was in effect while Vladimir Putin served his first and second terms; with the two-term limit, he was barred from the presidency in 2008. Instead, he served as Prime Minister while Dmitry Medvedev served as president for four years. Putin was re-elected to his third term in 2012; with the six-year term, he was elected to his fourth term in 2018. Article 81 specifies the method of election, including a secret ballot; Articles 82–93 detail powers, responsibilities, and limitations of the presidency. The constitution provides for a "strong presidency"; not only is the president the "Supreme Commander-in-Chief of the Armed Forces of the Russian Federation", the president also has the power to dissolve the State Duma.

Legislative branch
The legislature is the Federal Assembly of Russia, which consists of two chambers: the State Duma (the lower house) and the Federation Council (the upper house). The two chambers possess different powers and responsibilities: the State Duma is of more significance, as it carries the main responsibility for passing federal laws. Although a bill may originate in either legislative chamber (or be submitted by the President, government, local legislatures, Supreme Court, Constitutional Court, or High Arbitration Court), it must be first considered by the State Duma and be adopted by a majority vote before being turned over to the Federation Council, which has 14 days to take a vote on it. If the bill is adopted by the Federation Council, it must be signed by the President to become law. If rejected by the Federation Council, the bill will be returned to the State Duma, which can then override the council's rejection by passing it again with a two-thirds vote in the same form. The President has a final veto, but the State Duma and Federation Council also have an overriding power by passing with a two-thirds vote.

Judiciary
While the Russian Federation Constitution enumerates a strong and independent judicial branch, the reality is a question of debate. The constitution provides for judicial immunity, lifetime appointments/"irremovable" justices, the supremacy of the courts to administer justice, and affirms that judges need only submit to the constitution and the federal law. Additionally, Article 123 provides for open and fair trials, as well as equal application of the law. Three courts are delineated: Constitution Court of the Russian Federation, the Supreme Court of the Russian Federation, and the Higher Arbitration Court; each court is "appointed by the Council of the Federation upon the proposals by the President." The Constitution requires 19 judges for the Constitution Court, but does not specify the number of justices for the other courts. As of 2002, the Supreme Court has 115 members; due to the expansion of duties in 2014, the number of seats was increased to 170. In September 2014, the Institute of Modern Russia reported that the Russian Federation's Supreme Arbitration Court had been dissolved and that judicial matters previously under its authority had been transferred to the jurisdiction of the Supreme Court.

Amending the Constitution
The procedure for amending the Constitution is outlined in Chapter Nine. Proposals on amendments to and revision of the provisions of the Constitution of the Russian Federation may be submitted by the President of the Russian Federation, the Council of Federation, the State Duma, the Government of the Russian Federation, legislative (representative) bodies of constituent entities of the Russian Federation, and by groups consisting of not less than one fifth of the members of the Council of Federation or of the deputies of the State Duma.

Article 137 covers updating the provisions of Article 65 of the Constitution of Russia. An update regarding the change of the name of the subject of the Russian Federation is carried out by a decree of the President of Russia on bringing the name of the subject of the Russian Federation in the text of the Constitution of the Russian Federation in accordance with the decision of the subject of the Russian Federation. An update regarding changes in the subject composition of the Russian Federation is carried out in accordance with the federal constitutional law on the admission to the Russian Federation and the formation of a new constituent entity of the Russian Federation, on changes in the constitutional and legal status of the constituent entities of the Russian Federation, which should contain an indication of the inclusion of relevant changes or additions to Article 65 of the Constitution of Russia.

Article 136 covers updating the provisions of chapters 3, 4, 5, 6, 7, and 8 of the Constitution of Russia. An update is carried out in the form of a special act: a law of the Russian Federation on amendments to the Constitution, which is adopted by the parliament similarly to the federal constitutional law, but then also requires ratification by the legislative bodies of the constituent entities of the Federation. Moreover, one law of the Russian Federation on the amendment to the Constitution covers interrelated changes to the constitutional text; the law itself receives a name reflecting the essence of this amendment.

Article 135 covers updating the provisions of chapters 1, 2, and 9 of the Constitution of Russia. An update to any of these chapters is considered a revision of the Constitution's fundamental provisions, which is possible only through the adoption of the new Constitution of the Russian Federation by the Russian Constitutional Assembly or by popular vote.

2008 amendments
The amendments of 2008, which were proposed in November 2008 and came into force on 31 December 2008, are the first substantial amendments to the Constitution of Russia of 1993 and extended the terms of the President of Russia and the State Duma from four to six and five years, respectively. Earlier only minor adjustments concerning the naming of the federal subjects or their merging were made, which require a much simpler procedure.

July 2014 amendments
On 21 March 2014, Federal Constitutional Law No. 6 «On the Adoption of the Republic of Crimea into the Russian Federation and the Formation of New Subjects within the Russian Federation - the Republic of Crimea and the Federal City of Sevastopol» was adopted.

2020 amendments
The amendments of 2020 remove the "in a row" clause from the article regulating the maximum number of presidential terms, discounting previous presidential terms before the amendment enters into force. Other changes are recognition of Russia as a successor to the Soviet Union in relation to international organizations, treaties, and assets of the USSR stipulated by international treaties outside the territory Russian Federation, banning ceding Russian territory, diminishing the accomplishments by the "defenders of the fatherland" and their role in World War II is no longer allowed, and enshrining God and heterosexual marriage in the constitution. Other amendments would enshrine the role of the Russian language as that of "state forming people", a constitutional reference to God and giving statutory backing to the State Council.

From 25 June to 1 July 2020, a nationwide vote took place, with 78   % of voters voting in favor of the amendments with a turnout of 65    %, according to official results.

Putin signed an executive order on 3 July 2020 to officially insert the amendments into the Russian Constitution; they took effect on 4 July 2020.

2022 annexations
After the signing of "treaties of annexation" with Russian occupation authorities during the 2022 invasion of Ukraine, the text of the constitution was updated to include the Donetsk People’s Republic, Kherson Oblast, Luhansk People’s Republic, and Zaporizhzhia Oblast. As of December 2022, none of these territories is fully controlled by Russian forces, and Russian law does not define their borders: Kremlin spokesperson Dmitry Peskov stated that Russia will "continue consultations with the residents" as to the oblast borders, and that the people’s republics are annexed "in the 2014 borders", but high-level Russian collaborator Oleg Tsariov stated that "there are no 2014 borders".

Differences between the Constitution and the laws
The Constitution of Russia:

 * defines the state system, basic rights and freedoms, the form of the state and the system of supreme state authorities
 * has the highest legal force
 * has direct effect (the provisions of the constitution must be implemented regardless of whether other acts contradict them)
 * is characterized by stability due to a special, complicated order of acceptance and change
 * is the basis for the current legislation.

Numismatics
On December 10, 2018, a commemorative coin made of copper-nickel alloy with a nominal value of 25 rubles "The 25th anniversary of the adoption of the Constitution of the Russian Federation" was issued. On the reverse of the coin there is a relief image of an open book with a drawing of the coat of arms of the Russian Federation on the left page and the inscription "КОНСТИТУЦИЯ РОССИЙСКОЙ ФЕДЕРАЦИИ" on the right page. The commemorative coin was issued in a circulation of 1,000,000 and is a legal means of cash payment in the territory of the Russian Federation.

Former constitutions

 * October Manifesto (1905)
 * Russian Constitution of 1906
 * Decree on the system of government of Russia (1918)
 * Soviet Russia Constitution of 1918
 * Act on the establishment of the All-Russian supreme power (1918)
 * 1924 Constitution of the Soviet Union
 * Russian Constitution of 1925
 * 1936 Constitution of the Soviet Union
 * Russian Constitution of 1937
 * 1977 Constitution of the Soviet Union
 * Russian Constitution of 1978

Others

 * 2008 amendments to the Constitution of Russia
 * 2020 amendments to the Constitution of Russia
 * Constitution of the Soviet Union
 * Constitutional economics
 * Constitutionalism
 * Impeachment in Russia
 * Institute of State and Law
 * Law of the Russian Federation
 * Term limits in Russia
 * Human rights in Russia

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

title: Constitution of Russia


text:
Common collector

In electronics, a common collector amplifier (also known as an emitter follower) is one of three basic single-stage bipolar junction transistor (BJT) amplifier topologies, typically used as a voltage buffer.

In this circuit the base terminal of the transistor serves as the input, the emitter is the output, and the collector is common to both (for example, it may be tied to ground reference or a power supply rail), hence its name. The analogous field-effect transistor circuit is the common drain amplifier and the analogous tube circuit is the cathode follower.

Basic circuit
The circuit can be explained by viewing the transistor as being under the control of negative feedback. From this viewpoint, a common-collector stage (Fig. 1) is an amplifier with full series negative feedback. In this configuration (Fig. 2 with β = 1), the entire output voltage Vout is placed contrary and in series with the input voltage Vin. Thus the two voltages are subtracted according to Kirchhoff's voltage law (KVL) (the subtractor from the function block diagram is implemented just by the input loop), and their difference Vdiff = Vin − Vout is applied to the base–emitter junction. The transistor continuously monitors Vdiff and adjusts its emitter voltage to equal Vin minus the mostly constant VBE by passing the collector current through the emitter resistor RE. As a result, the output voltage follows the input voltage variations from VBE up to V+; hence the name "emitter follower".

Intuitively, this behavior can be also understood by realizing that VBE is very insensitive to bias changes, so any change in base voltage is transmitted (to good approximation) directly to the emitter. It depends slightly on various disturbances (transistor tolerances, temperature variations, load resistance, a collector resistor if it is added, etc.), since the transistor reacts to these disturbances and restores the equilibrium. It never saturates even if the input voltage reaches the positive rail.

The common-collector circuit can be shown mathematically to have a voltage gain of almost unity:

A_v = \frac{v_\text{out}}{v_\text{in}} \approx 1. $$

A small voltage change on the input terminal will be replicated at the output (depending slightly on the transistor's gain and the value of the load resistance; see gain formula below). This circuit is useful because it has a large input impedance

r_\text{in} \approx \beta_0 R_\text{E}, $$ so it will not load down the previous circuit, and a small output impedance

r_\text{out} \approx \frac{R_\text{E} \parallel R_\text{source}}{\beta_0}, $$ so it can drive low-resistance loads.

Typically, the emitter resistor is significantly larger and can be removed from the equation:

r_\text{out} \approx \frac{R_\text{source}}{\beta_0}. $$

Applications

The common collector amplifier's low output impedance allows a source with a large output impedance to drive a small load impedance without changing its voltage. Thus this circuit finds applications as a voltage buffer. In other words, the circuit has current gain (which depends largely on the hFE of the transistor) instead of voltage gain. A small change to the input current results in much larger change in the output current supplied to the output load.

One aspect of buffer action is transformation of impedances. For example, the Thévenin resistance of a combination of a voltage follower driven by a voltage source with high Thévenin resistance is reduced to only the output resistance of the voltage follower (a small resistance). That resistance reduction makes the combination a more ideal voltage source. Conversely, a voltage follower inserted between a small load resistance and a driving stage presents a large load to the driving stage—an advantage in coupling a voltage signal to a small load.

This configuration is commonly used in the output stages of class-B and class-AB amplifiers. The base circuit is modified to operate the transistor in class-B or AB mode. In class-A mode, sometimes an active current source is used instead of RE (Fig. 4) to improve linearity and/or efficiency.

Characteristics
At low frequencies and using a simplified hybrid-pi model, the following small-signal characteristics can be derived. (Parameter $$\beta = g_m r_\pi$$ and the parallel lines indicate components in parallel.)

Where $$R_\text{source}\ $$ is the Thévenin equivalent source resistance.

Derivations
Figure 5 shows a low-frequency hybrid-pi model for the circuit of Figure 3. Using Ohm's law, various currents have been determined, and these results are shown on the diagram. Applying Kirchhoff's current law at the emitter one finds:
 * $$(\beta + 1) \frac{v_\text{in} - v_\text{out}}{R_\text{S} + r_\pi} = v_\text{out} \left(\frac{1}{R_\text{L}} + \frac{1}{r_\text{O}}\right).$$

Define the following resistance values:
 * $$\begin{align}

\frac{1}{R_\text{E}} &= \frac{1}{R_\text{L}} + \frac{1}{r_\text{O}}, \\[2pt] R &= \frac{R_\text{S} + r_\pi}{\beta + 1}. \end{align}$$ Then collecting terms the voltage gain is found:
 * $$A_\text{v} = \frac{v_\text{out}}{v_\text{in}} = \frac{1}{1 + \frac{R}{R_\text{E}}}.$$

From this result, the gain approaches unity (as expected for a buffer amplifier) if the resistance ratio in the denominator is small. This ratio decreases with larger values of current gain β and with larger values of $$R_\text{E}$$. The input resistance is found as
 * $$\begin{align}

R_\text{in} &= \frac{v_\text{in}}{i_\text{b}} = \frac{R_\text{S} + r_\pi}{1 - A_\text{v}} \\ &= \left(R_\text{S} + r_\pi\right)\left(1 + \frac{R_\text{E}}{R}\right) \\ &= R_\text{S} + r_\pi + (\beta + 1) R_\text{E}. \end{align}$$ The transistor output resistance $$r_\text{O}$$ ordinarily is large compared to the load $$R_\text{L}$$, and therefore $$R_\text{L}$$ dominates $$R_\text{E}$$. From this result, the input resistance of the amplifier is much larger than the output load resistance $$R_\text{L}$$ for large current gain $$\beta$$. That is, placing the amplifier between the load and the source presents a larger (high-resistive) load to the source than direct coupling to $$R_\text{L}$$, which results in less signal attenuation in the source impedance $$R_\text{S}$$ as a consequence of voltage division.

Figure 6 shows the small-signal circuit of Figure 5 with the input short-circuited and a test current placed at its output. The output resistance is found using this circuit as
 * $$R_\text{out} = \frac{v_\text{x}}{i_\text{x}}.$$

Using Ohm's law, various currents have been found, as indicated on the diagram. Collecting the terms for the base current, the base current is found as
 * $$(\beta + 1) i_\text{b} = i_\text{x} - \frac{v_\text{x}}{R_\text{E}},$$

where $$R_\text{E}$$ is defined above. Using this value for base current, Ohm's law provides
 * $$v_\text{x} = i_\text{b} \left(R_\text{S} + r_\pi\right).$$

Substituting for the base current, and collecting terms,
 * $$R_\text{out} = \frac{v_\text{x}}{i_\text{x}} = R \parallel R_\text{E},$$

where || denotes a parallel connection, and $$R$$ is defined above. Because $$R$$ generally is a small resistance when the current gain $$\beta$$ is large, $$R$$ dominates the output impedance, which therefore also is small. A small output impedance means that the series combination of the original voltage source and the voltage follower presents a Thévenin voltage source with a lower Thévenin resistance at its output node; that is, the combination of voltage source with voltage follower makes a more ideal voltage source than the original one.

title: Common collector


text:
Pi Beta Phi

Pi Beta Phi (ΠΒΦ), often known simply as Pi Phi, is an international women's fraternity founded at Monmouth College, in Monmouth, Illinois on April 28, 1867, as I. C. Sorosis, the first national secret college society of women to be modeled after the men's Greek-letter fraternity.

Pi Phi's headquarters are located in Town and Country, Missouri. Since its founding, the fraternity has installed over 200 chapters and more than 300 alumnae organizations across the United States and Canada. Most of the fraternity's official philanthropies fall under the category of education/literacy programs or the preservation of traditional arts and crafts. Pi Beta Phi is one of 26 international sororities which are members under the umbrella organization of the National Panhellenic Conference.

History
Pi Beta Phi was founded as a secret organization under the name of I. C. Sorosis on 1867-04-28 at Monmouth College in Monmouth, Illinois. Pi Beta Phi is regarded as the first national women's fraternity. The founders were: • Clara Brownlee Hutchinson

• Libbie Brook Gaddis

• Emma Brownlee Kilgore

• Margaret Campbell

• Rosa Moore

• Ada Bruen Grier

• Nancy Black Wallace

• Jennie Horne Turnbull

• Rachel Jane "Jennie" Nicol

• Inez Smith Soule

• Fannie Thomson

• Fannie Whitenack Libbey The organization was formed "to enjoy the benefits of a secret society similar to those formed by collegiate men." They planned their society at a home where two of the women rented a room, choosing I. C. Sorosis as the name and "Pi Beta Phi" as the motto.

Shortly after the founding, the sisters had a jeweler design their official badge: a golden arrow with the letters "I. C." on the wings. When the name was changed to "Pi Beta Phi," the Greek letters replaced "I. C." on the wings. At the Yellowstone Convention of 1934, they voted to limit the links in the badge's chain; there are 12, one for each of the founders.

The first fraternity convention was held in 1868 at the home of Fannie Thomson in Oquawka, Illinois. The fraternity's second chapter was established that same year at Iowa Wesleyan College in Mount Pleasant, Iowa. The expansion made Pi Beta Phi the first national (multi-chapter) women's secret society.

Name change and NPC membership
At the 1882 convention, the society officially adopted its motto as well as the fraternity colors of wine and silver blue. It began to use Greek letters as its name six years later in 1888, when the name was changed from I. C. Sorosis to Pi Beta Phi. In 1893, with the number of alumnae members growing, the fraternity organized a national alumnae department. Cooperation among women's fraternities and sororities was formalized in 1902 with the founding of the National Panhellenic Conference, of which Pi Beta Phi was a founding member. Meanwhile, chapter expansion continued, and in 1908 the fraternity's first Canadian chapter was established at the University of Toronto.

The fraternity's first philanthropy, Pi Beta Phi Settlement School, was organized in Gatlinburg, Tennessee, in 1912. In 1913, the fraternity created local Alumnae Advisory Committees to support its chapters individually. Central Office, the fraternity headquarters, was established in 1925.

In the 1960s, G. William Domhoff, writing in Who Rules America?, listed Pi Beta Phi as one of "the four or five sororities with nationwide prestige."

Symbols
The official symbol of Pi Beta Phi is the arrow, and the official flower is the wine carnation. The fraternity colors are wine and silver blue. The unofficial mascot is the angel, nicknamed "Angelica". Pi Beta Phi does not have an official gemstone.

The crest is a lozenge emblazoned with the crest of the Brownlee family, two of whom were founders of the fraternity. The badge (pin) is a golden arrow. The pledge pin is a golden arrowhead with the Greek letter Βeta.

The Kansas Alpha chapter began publication of The Arrow in 1885; it would eventually become a quarterly magazine published by the international fraternity for all its members. Today, dues-paying alumnae receive The Arrow by mail, while others receive it annually and can access it online at the fraternity's web site year round.

Chapters and alumnae clubs
Pi Beta Phi alumnae, initiated members in good standing who have graduated or otherwise left their college or university, can organize into local alumnae clubs which are recognized by the fraternity. Like collegiate chapters, alumnae clubs are grouped geographically into regions, which is led by an Alumnae Regional Director.

Governance
The international fraternity is governed by a Grand Council, elected at each biennial convention and comprising a Grand President and six Grand Vice Presidents (Alumnae, Collegians, Finance/Housing, Community Relations, Fraternity Growth, and Member Experience). Also elected biennially are seven international Directors (Alumnae, Operations, Finance/Housing, Community Relations, Recruitment, Risk Management and Member Experience) and two Directors for each region (Collegiate Regional Director and Alumnae Regional Director). The work of Directors is supervised by a member of Grand Council.

In addition to the elected officers, there are several appointed international officers assigned certain functions, such as an archivist and a fraternity historian.

Philanthropies
Like many sororities and fraternities, Pi Beta Phi members take part in a number of philanthropy programs. Over the fraternity's history, philanthropies have included education, literacy, and the preservation of regional arts and crafts.

In 1990, Pi Beta Phi created the Pi Beta Phi Foundation, a 501(c)(3) charitable organization.

Read > Lead > Achieve
Pi Phi's philanthropy is called Read>Lead>Achieve and is centered around children's literacy. Pi Phi's believe in unlocking the power of reading to create a more literate and productive society. In order to do so, Pi Phi has started a reading enrichment program for students in pre school through third grade called, "Champions are Readers". This program is funded through the Pi Beta Phi foundation and provides students with all materials needed for the program. Additionally, members can join a virtual book club to share their love of reading with their sisters.

Educational and cultural philanthropies
Pi Beta Phi opened the Pi Beta Phi Settlement School in Gatlinburg, Tennessee, in 1912 to provide education, economic opportunity, and health care to the rural area. Over the years, as the community took over childhood education, Settlement School began to adapt by offering arts and crafts classes in an effort to preserve and promote the region's crafts tradition. An extension of the Pi Beta Phi Settlement School called the Craft Work Shop was begun in 1945 in cooperation with the University of Tennessee. Now an independent nonprofit organization known as the Arrowmont School of Arts and Crafts, it is one of the oldest arts and crafts centers in the South.

Local chapter or member misconduct
In 2005, the chapter at the University of California, Los Angeles was penalized for hazing pledges.

In 2010, the chapter at Cornell University received national attention after the release of a seven-page email sent to members of the chapter to address what is acceptable and unacceptable attire for recruitment. The tone of the e-mail—with lines such as "No muffin tops or camel toe" and "I will not tolerate any gross plastic shizz [jewelry]"—drew criticism from the Huffington Post and many online young adult forums.

In 2010, the chapter at the Miami University was suspended for one year after underage drinking, vomiting, littering, and damaging Lake Lyndsay Lodge in Hamilton, Ohio. In August 2017, the organization closed its chapter at Miami, saying that "... the decision was made because the membership experience has routinely fallen below Fraternity expectations, particularly in regards to risk management and the lack of commitment to Pi Beta Phi's core values."

In 2012, the chapter at Bucknell University was suspended for at least three years for violation of the international chapter's policy and position statements regarding event planning-management and alcohol use. The chapter has since closed permanently.

In 2013, the chapter at the University of Nevada at Reno was banned from campus until the last active member graduated due to repeated hazing violations.

In 2013 and 2014, sorority women from multiple chapters at the University of Alabama – including Pi Beta Phi, Kappa Delta, Chi Omega, Delta Delta Delta, Alpha Omicron Pi, and Alpha Gamma Delta – alleged that either active members or some of their alumnae had prevented them from offering membership to black candidates because of their race. An anonymous Pi Beta Phi member told the university newspaper, The Crimson White, that alumnae threatened to cut financial support from the chapter if they offered membership to a black candidate the chapter had wanted to recruit. Students held a campus march to integrate Greek life on campus, and following media and national outcry, the university held a second round of recruitment in hopes of offering membership to more women, including black women. In 2021, Emory University's chapter faced allegations of racism and sexual assault cover-ups.

title: Pi Beta Phi


text:
St. Mary's Basilica, Kraków

Saint Mary's Basilica (Kościół Mariacki) is a Brick Gothic church adjacent to the Main Market Square in Kraków, Poland. Built in the 14th century, its foundations date back to the early 13th century and serve as one of the best examples of Polish Gothic architecture. Standing 80 m (262 ft) tall, it is particularly famous for its wooden altarpiece carved by Veit Stoss (Wit Stwosz). Some of its monumental polychrome murals were designed by Poland's leading history painter, Jan Matejko (1838–1893). In 1978 it became a UNESCO World Heritage Site alongside the Historic Centre of Kraków.

On every hour, 24 hours a day, 365 days a year, a trumpet signal—called the Hejnał mariacki—is played from the top of the taller of Saint Mary's two towers. The plaintive tune breaks off in mid-stream, to commemorate a famous 13th century trumpeter who was shot in the throat while sounding the alarm before a Mongol attack on the city. The noon-time hejnał is heard across Poland and abroad broadcast live by Polish Radio Jedynka.

Saint Mary's Basilica also served as an architectural model for many of the churches that were built by the Polish diaspora abroad, particularly those like Saint Michael's and Saint John Cantius in Chicago, designed in the Polish Cathedral style.

The church is familiar to many English-speaking readers from the 1928 book The Trumpeter of Krakow by Eric P. Kelly.

History
According to chronicler Jan Długosz, Saint Mary's Basilica in the Main Square in Kraków was founded in 1221–22 by the Bishop of Kraków, Iwo Odrowąż. The building was destroyed during the Mongol invasion of Poland. Between 1290 and 1300 the new early Gothic church was built on the remaining foundations. It was consecrated twenty years later, in 1320.

The church was completely rebuilt during the reign of Casimir III the Great between 1355 and 1365 with substantial contributions from wealthy restaurateur Mikołaj Wierzynek. The presbytery was elongated and tall windows added. The main body of the church was completed in 1395–97 with the new vault constructed by master Nicholas Wernher from Prague. However, the vault over the presbytery collapsed in 1442 due to a possible earthquake, which has never happened before nor since in Kraków.

In the first half of the 15th century, the side chapels were added. Most of them were the work of master Franciszek Wiechoń. At the same time the northern tower was raised and designed to serve as the watch tower for the entire city. In 1478 carpenter Maciej Heringh (or Heringk) funded a helmet for the tower. A gilded crown was placed on it in 1666, which is still present today. At the end of the 15th century, Saint Mary's church was enriched with a sculptural masterpiece, an Altarpiece of Veit Stoss (Ołtarz Mariacki Wita Stwosza) of late Gothic design.

In 1536/37, King Sigismund I. declared that the sermons in the church should be changed from German to Polish. The large German community of Kraków were relocating their place of worship to the smaller Saint Barbara's church.

In the 18th century, by the decision of vicar Jacek Augustyn Łopacki, the interior was rebuilt in the late Baroque style. The author of this work was Francesco Placidi. All 26 altars, equipment, furniture, benches and paintings were replaced and the walls were decorated with polychrome, the work of Andrzej Radwański. In the years immediately before 1730 the Venetian painter Giambattista Pittoni painted five altarpieces for the side altars of the central nave: The Annunciation, The Adoration of the Magi, Madonna and Child with St. Philip Neri, Mary Magdalene, St. Sebastian.

At the beginning of the 19th century, the city decided that a cemetery near the basilica was to be shut down and replaced by a public square. Today, it is known as Plac Mariacki (Marian Square). In the years 1887–1891, under the direction of Tadeusz Stryjeński, the neo-Gothic design was introduced into the basilica. The temple gained a new design and murals painted and funded by Jan Matejko, who worked with Stanisław Wyspiański and Józef Mehoffer - the authors of stained glass in the presbytery.

Since the beginning of 1990s, the basilica underwent an extensive renovation. In 2003, in the final stage of the works, the roof of the church was replaced.

On 18 April 2010, in Saint Mary's Basilica, a funeral ceremony for Polish president Lech Kaczyński and his wife Maria was held. The coffins were later transported and buried in one of the crypts of Wawel Cathedral.

title: St. Mary's Basilica, Kraków


text:
Brothers Keepers

Brothers Keepers is a German-based transnational anti-racism project, bringing together hip hop, reggae and soul musicians, headed primarily by Afro-Germans. Their debut single, "Adriano-Letzte Warnung", was written in response to the murder of Alberto Adriano by Neo-Nazis. It remains their most popular release, with more than 6 million views on YouTube.

History
The idea for the project took root when a German of Mozambiquan origin, named Alberto Adriano, was brutally killed by neo-Nazis in Dessau in 2000. A group of musicians decided to organize and fight back.

The following quote is about Adriano's death and its effect.

Original: Als Alberto Adriano an Pfingsten 2000 von Neonazis in Dessau ermordet wird, hinterlässt er eine Ehefrau und drei Kinder – eine Familie, die nun nicht nur lernen muss, ohne ihren Vater und Mann zu leben, sondern zugleich verstehen muss, dass er starb, weil er ein Schwarzer war.

English: Alberto Adriano, killed on pentecost 2000 by neo-nazis in Dessau, is survived by a wife and three children - a family that not only must learn to live without a father and husband, but also has to understand that he died because he was black.

Brothers Keepers has local groups active in information campaigns, presenting teach-ins at schools etc. However the project primarily gained prominence in Germany through the collaborative album, Lightkultur. The title is a pun on conservative politician Günther Beckstein’s term "deutsche Leitkultur" ("German leading culture"), demanding that foreigners subject themselves to the supposed standards of German culture. The album features German musicians such as Torch, Samy Deluxe, Afrob, Denyo from the Beginner and D-Flame. The proceeds of this album went to charity.

Politicization/Critique
Brothers Keepers faced much criticism and disapproval despite being one of the first groups of Afro-German hip-hop artists that broke into the mainstream while addressing the struggles behind the Afro-German racial identity. On the one hand, the rappers are denounced for being "too German." As described by Fatima El-Tayeb, "Black Germans’ attempt to make their country their home by creating a space for themselves on its imaginary map – a step which, if successful, would mean a dramatic reconfiguration of ‘Germanness’ – is held against them by exactly those white Germans who most decry the nation's anachronistic and exclusionary concept of identity." On the other hand, they are also criticized, mostly by white German liberals, for being too Black, racially exclusive, and anti-multicultural. They also received charges for perpetuating male dominance and masculinity that undermines the notable role that women and feminism asserted during the early stages of the Hip Hop movement. The main concern is that while they have made significant contributions to the protest against racial divides and essentialization for the Afro-German community in large, they might have done so in a way that fails to subvert gender stereotypes and is quite often offensive, if not hostile, towards women.

Gender dynamics
Brothers Keepers presented themselves and delivered their message in traditionally masculine ways. Their presentation was heavily influenced by the Black masculinity of mainstream American Hip-Hop, but maintained a distinctly Afro-German identity and spoke to Afro-German issues. Especially in lyrics and videos that were explicitly against Nazism and anti-Blackness in Germany, they formed a confrontational masculine collectivity. This was reaffirmed by their exclusion of women from their music and videos, an absence which they claimed was due to female performers being pregnant or on maternity leave. Some of the female performers in question, Sisters Keepers, contrasted with that masculinity with a rhetoric of peace and coalition-building rather than direct confrontation. In fact, in the music video for Sisters Keepers's "Liebe und Verstand," members of Brothers Keepers make visual and auditory cameos, giving the song a gendered authenticity. Although Brothers Keepers sought to reaffirm Afro-German identity with a masculinist perspective, it is important to note that the formation of the Afro-German identity was done largely by Afro-German women.

Black Lesbian feminist theorist and poet Audre Lorde can be identified as instrumental in facilitating contemporary articulations of Black Germanness. In 1984, Lorde visited Berlin and met with Black German women (such as Maya Ayim, Katharina Oguntoye, and Ika Hügel-Marshall) and coined the term "Afro-German". Following the consolidation of terminology, a movement emerged led by the publication of Farbe bekennen (translated as Showing Our Colors: Afro-German Women Speak Out). Then, several organizations coalesced to critique the racism of the German feminist movement, including Initiative Schwarze Deutsche" (ISD), and "Afro-deutsche Frauen" (ADEFRA). These organizations' early activities involved publishing magazines and organizing the first Black History Month celebrations in Berlin. They were foundational for community building along gendered and racialized lines in Germany and elsewhere, and they were pioneered by Afro-German women.

As hip-hop became means of forwarding Afro-German activism, Brother Keepers’ select historical consciousness demonstrates how "the strong presence of women – articulate, feminist, often lesbian – in the first decades of the Afro-German struggle has been hard for young male MCs to stomach, given that they generally model themselves after images of black masculinity that are often deeply sexist and homophobic". In other words, "By relegating female performers to the margins... Brothers Keepers runs counter to the strong presence of women and feminism in the history of Afro-German political organizing". Brother Keepers’ female counterpart, Sisters Keepers, emerged as an ostensible afterthought, and in their collaboration, Sisters Keepers were relinquished to the background as apolitical and demure sidekicks. This representation is a far cry from the true role Afro-German women have played in activism. Sisters Keepers later diverged from Brother Keepers, renaming themselves to "Sisters" and releasing the more radical record Gender Riots in 2008.

Song lyrics
The lyrics on the album are influenced by Black Power rhetoric and are militantly anti-Nazi, proposing solutions to racism ranging from education to violence. The militancy is especially well illustrated in the German Top 10 hit "Adriano", a seven-minute tour de force produced by DJ Desue, featuring the crème of German rap. Its video shows a procession of rappers, marching as a united front and the chorus, sung by South African-descended R&B star Xavier Naidoo, goes thus:

Original: Dies' ist so 'was wie eine letzte Warnung, / Denn unser Rückschlag ist längst in Planung. / Wir fall’n darein, wo ihr auffallt, / Wir bieten eurer braunen Scheiße endlich Aufhalt. / Denn was ihr sucht, ist das Ende. / Und was wir reichen sind geballte Fäuste und keine Hände. / Euer Niedergang für immer! / Und was wir hören denn ist euer Weinen und euer Gewimmer.

English: "This is something like a final warning, / As we have been planning our counterstrike for a long time. / We intervene where you emerge, / At last, we offer resistance to your brown shit. / ‘Cause what you want is the end. / And what we offer are clenched fists and not our hands. / Your downfall forever! / And what we’ll hear is your crying and your whimpering."

or

Ich sage K, sage Z, sage Nazis rein / Ich will nicht labern, denn ich kenn mein Vaterland / Macht es mich krank wie Masern, dann verspür ich Tatendrang / Ich fühle mich eingeengt und will statt Prominenz / Und statt großer Fans, Nazis die wie Poster hängen.

"I say K, I say Z, I say Nazis inside / I don't wanna talk 'cause I know my country / Does it make me sick like measles, then I wanna act / Then I feel constricted and want instead of prominence / and lots of fans, Nazis who hang like posters."

The project is not limited to Germany. It focuses on manifestations of the African diaspora throughout the world and is supported by international artists such as Jamaican reggae musician Ziggy Marley and Senegalese mbalax musician Youssou N'Dour. There is a UK Brothers Keepers, which, while lacking the organizational superstructure of its German counterpart, contributed a track to Lightkultur.

There is also a female version of this Movement/Band called the Sisters Keepers consisting of Nadja Benaissa, Ayọ, Kaye, Nicole Hadfield (Groove Guerrilla), and Tamika, along with Tesiree, Lisa, Mamadee, Pat and Meli (Skills en Masse, Ischen Impossible) with Onejiru (Pielina Schindler).

Performers
A list is available on the website.

 * Adé Bantu
 * Afrob
 * Chima
 * Denyo
 * D-Flame
 * Don Abi
 * Ebony Prince, Germ
 * Eased of Seeed
 * Gentleman
 * Harry Belafonte
 * Joachim Deutschland
 * Jah Meek
 * Nosliw
 * Ono Ngcala
 * Patrice Bart-Williams
 * Such A Surge
 * Sékou
 * Samy Deluxe
 * Toni L
 * Torch
 * Tyron Ricketts
 * UB40
 * Xavier Naidoo
 * Youssou N’Dour
 * Ziggy Marley

title: Brothers Keepers


text:
Wingsuit flying

Wingsuit flying (or wingsuiting) is the sport of skydiving using a webbing-sleeved jumpsuit called a wingsuit to add webbed area to the diver's body and generate increased lift, which allows extended air time by gliding flight rather than just free falling. The modern wingsuit, first developed in the late 1990s, uses a pair of fabric membranes stretched flat between the arms and flanks/thighs to imitate an airfoil, and often also between the legs to function as a tail and allow some aerial steering.

Like all skydiving disciplines, a wingsuit flight almost always ends by deploying a parachute, and so a wingsuit can be flown from any point that provides sufficient altitude for flight and parachute deployment – a drop aircraft, or BASE-jump exit point such as a tall cliff or mountain top. The wingsuit flier wears parachuting equipment specially designed for skydiving or BASE jumping. While the parachute flight is normal, the canopy pilot must unzip arm wings (after deployment) to be able to reach the steering parachute toggles and control the descent path.

Wingsuits are sometimes referred to as "birdman suits" (after the brand name of the makers of the first commercial wingsuit), "squirrel suits" (from their resemblance to flying squirrels' wing membrane), and "bat suits" (due to their resemblance to bat wings or perhaps the aptly named DC Comics superhero Batman and his signature costume).

History
An early attempt at wingsuit flying was made on 4 February 1912 by a 33-year-old tailor, Franz Reichelt, who jumped from the Eiffel Tower to test his invention of a combination of parachute and wing, which was similar to modern wingsuits. He misled the guards by saying that the experiment was going to be conducted with a dummy. He hesitated quite a long time before he jumped, and died when he hit the ground head first, opening a measurable hole in the frozen ground.

A wingsuit was first used in the US in 1930 by a 19-year-old American, Rex G Finney of Los Angeles, California. The goal was to increase horizontal movement and maneuverability during a parachute jump. These early wingsuits used materials such as canvas, wood, silk, steel, and whalebone. They were not very reliable, although some "birdmen", such as Clem Sohn and Leo Valentin, claimed to have glided for miles.

Batwings, a precursor to wingsuits, were showcased in the 1969 film, The Gypsy Moths, starring Burt Lancaster and Gene Hackman.

In the mid-1990s, the modern wingsuit was developed by Patrick de Gayardon of France, adapted from the model used by John Carta. In 1997, the Bulgarian Sammy Popov designed and built a wingsuit that had a larger wing between the legs and longer wings on the arms. He tested his prototype in a vertical wind tunnel in Las Vegas at Flyaway Las Vegas. Popov's wingsuit first flew in October 1998, but never went into commercial production. In 1998, Chuck "Da Kine" Raggs built a version that incorporated hard ribs inside the wing airfoils. Although these more rigid wings were better able to keep their shape in flight, this made the wingsuit heavier and more difficult to fly. Raggs' design also never went into commercial production. Flying together for the first time, Popov and Raggs showcased their designs side by side at the World Free-fall Convention at Quincy, Illinois, in August 1999. Both designs performed well. At the same event, jumpers performed formation wingsuit skydives with de Gayardon's, Popov's, and Raggs' suits.

Commercial era
In 1999, Jari Kuosma of Finland and Robert Pečnik of Croatia teamed up to create a wingsuit that was safe and accessible to all skydivers. Kuosma established Bird-Man International Ltd. the same year. BirdMan's "Classic", designed by Pečnik, was the first wingsuit offered to the general skydiving public. BirdMan was the first manufacturer to develop an instructor program. Created by Kuosma, the instructor program's aim was to remove the stigma that wingsuits were dangerous and to provide wingsuit beginners (generally, skydivers with a minimum of 200 jumps) with a way to safely enjoy what was once considered the most dangerous feat in the skydiving world. With the help of Birdman instructors Scott Campos, Chuck Blue, and Kim Griffin, a standardized program of instruction was developed that prepared instructors. Wingsuit manufacturers Squirrel Wingsuits, TonySuits Wingsuits, Phoenix-Fly, Fly Your Body, and Nitro Rigging have also instituted coach training programs.

Launch
A wingsuit pilot enters free fall wearing both a wingsuit and parachute equipment. The details of a wingsuit launch depend on whether it is a skydive from an aircraft, or a BASE jump from a fixed object.

Exiting an aircraft in a wingsuit requires skills that differ depending on the location and size of the door. These techniques include the orientation relative to the aircraft and the airflow while exiting. It is also important that wingsuit pilots spread their legs and arms at the proper time to avoid hitting the tail or becoming unstable. The wingsuit immediately starts to fly upon exiting the aircraft in the relative wind generated by the forward speed of the aircraft.

Exiting from a BASE jumping site, such as a cliff, requires a different technique. In these situations, a vertical drop using the forces of gravity generates the airspeed that wingsuits need to generate lift. This is also the case when exiting from a helicopter, a paraglider, or a hot air balloon. Unlike when exiting an airplane, it takes time to build up airspeed to inflate the wingsuit and provide aerodynamic control. So exiting the cliff in a proper orientation is critical.

Glide
A wingsuit modifies the body area exposed to wind to increase the desired amount of lift and drag generated by the body. With training, wingsuit pilots can achieve sustained glide ratio of 3:1 or more. This means that for every meter dropped, three meters are gained moving forward. By adjusting body configuration, fliers can alter both their forward speed and fall rate. The pilot manipulates these flight characteristics by changing the shape of the torso, de-arching and rolling the shoulders and moving hips and knees, and by changing the angle of attack in which the wingsuit flies in the relative wind, and by the amount of tension applied to the fabric wings of the suit. The absence of a vertical stabilizing surface results in little damping around the yaw axis, so poor flying technique can result in a spin that requires active effort on the part of the skydiver to stop.

A typical skydiver's terminal velocity in belly to earth orientation ranges from 180 to 225 km/h (110 to 140 mph). A wingsuit can reduce these speeds dramatically. A vertical instantaneous velocity of 40 km/h (25 mph) has been recorded. However the speed at which the body advances forward through the air is still much higher (up to 100 km/h [62 mph]).

The glide ratios of older wingsuits made in the 1990s through the early 2010s were closer to 2:1. It was possible for expert flyers to achieve a 3:1 ratio but this was very difficult. However, advancements in modern wingsuits allow flyers to achieve a 3:1 ratio much more easily, allowing for higher speeds.

Flare
Wingsuits can perform a flare in which airspeed is exchanged for additional lift. By first diving to build up speed, modern wingsuits can flare enough to gain altitude, but only for a short time.

Deployment
At a planned altitude above the ground in which a skydiver or BASE jumper typically deploys the parachute, wingsuit fliers will also deploy their parachutes. Before deployment, pilots adjust their flight configuration by flaring to reduce their air speed. The pilot then reaches back and throws a pilot chute to initiate the parachute deployment sequence. The parachute is flown to a controlled landing at the desired landing spot using typical skydiving or BASE jumping techniques.

Record-keeping
Wingsuit pilots often use tools including portable GPS receivers to record their flight path. This data can be analyzed later to evaluate flight performance in terms of fall rate, speed, and glide ratio. When jumping for the first time at a new location, BASE jumpers will often evaluate terrain using maps and laser range finders. By comparing a known terrain profile with previously recorded flight data, jumpers can objectively evaluate whether a particular jump is possible. BASE jumpers also use landmarks, along with recorded video of their flight, to determine their performance relative to previous flights and the flights of other BASE jumpers at the same site.

Suit design
Modern wingsuits use a combination of materials in order to create an airfoil shape. The main surface is typically made from ripstop nylon, with various materials used to reinforce the leading edge, and reduce drag.
 * The tri-wing wingsuit has three individual ram-air wings attached under the arms and between the legs.
 * The mono-wing wingsuit design incorporates the whole suit into one large wing.

Beginner wingsuits have less surface area and lower internal pressure. This makes them easier to control and less likely to go unstable in flight. Less fabric material makes it easier to deploy the pilot chute at the end of the flight. With experience, pilots can choose to upgrade to more advanced suits that have more surface area and increased glide performance.

The air foil shape is formed by pressure inside the wing and the construction of the suit. Internal ribs help form the shape. Having a smooth leading edge is especially important as it is the source of most lift and most drag. Reducing inlet drag while maintaining high internal suit pressure is also important in modern wingsuit design. The number of air inlets and their positions vary on different suit designs. Suits which are focused on freestyle flight often have inlets on the back surface of the suit to maintain internal pressure when pilots are "back flying" in a face up orientation.

A 2010 redesign tested in a wind tunnel by the 8th Conference of the International Sports Engineering Association (ISEA) found that adding material to the wingsuit between the head/helmet area and connecting it to the wrist, thus increasing upper wings' size, would "...lower lift-to-drag ratio in most testing scenarios. The decrease in lift-to-drag ratio was due to the combination of an increased lift and a higher increased drag." Other innovations in the late 2000s and early 2010's helped increase the glide ratio further.

Wingsuit BASE
As compared to skydiving from an airplane, BASE jumping involves jumping from a "fixed object" such as a cliff. BASE jumping in its modern form has existed since at least 1978, but it was not until 1997 that Patrick de Gayardon made some of the first-ever wingsuit BASE jumps combining the two disciplines. Compared to normal BASE jumping, wingsuit BASE jumping allows pilots to fly far away from the cliffs they jumped from, and drastically increase their freefall time before deploying a parachute. Since 2003, many BASE jumpers have started using wingsuits, giving birth to wingsuit BASE.

A wingsuit BASE jump begins by jumping from a cliff. Within seconds, air inflates the suit into a semi-rigid airfoil shape. By holding a proper body position, the wingsuit flier is able to glide forward at a ratio of 3:1, meaning that they are moving forward three feet for every foot of descent (or 3 meters for every meter of descent).

As suit technology and pilot skill have improved, wingsuit BASE jumpers have learned to control their flight so that they can fly just meters away from terrain. “Proximity flying” is the practice of flying a wingsuit close to the faces and ridges of mountains. Flying near terrain gives a greater sense of speed due to having a close visual reference. Loic Jean-Albert of France is one of the first proximity flyers, and his pioneering flying brought many BASE jumpers into the sport. In November 2012, Alexander Polli became the first wingsuit BASE jumper to successfully strike a wingsuit target. Polli died August 22, 2016, in a wingsuit accident, after crashing into a tree.

Wingsuit BASE jumping carries additional risk beyond a wingsuit skydive. Jumping from a fixed object means starting with low airspeed which requires different flying positions and skills. During the flight, hazards exist such as trees, rocks and the ground which must be avoided. While skydivers typically carry two parachutes, a main and a reserve, wingsuit BASE jumpers typically only carry one BASE-specific parachute.

Wingsuit BASE jumping is an unregulated sport. But to perform the activity safely requires jumpers to be an experienced skydiver, wingsuit pilot, and BASE jumper. It takes hundreds of practice jumps to achieve skill in each of these disciplines before considering wingsuit BASE.

Jet-powered wingsuits
As of 2010, there have been experimental powered wingsuits, often using small jet engines strapped to the feet or a wingpack setup to allow for even greater horizontal speeds and even vertical ascent.

On 25 October 2009, in Lahti, Finland, Visa Parviainen jumped from a hot air balloon in a wingsuit with two small turbojet engines attached to his feet. The engines provided approximately 160 N (16 kgf, 35 lbf) of thrust each and ran on JET A-1 fuel. Parviainen achieved approximately 30 seconds of horizontal flight with no noticeable loss of altitude. Parviainen continued jumping from hot air balloons and helicopters, including one for the Stunt Junkies program on Discovery Channel.

Christian Stadler from Germany invented the "VegaV3 wingsuit system" that uses an electronic adjustable hydrogen peroxide rocket. The rocket provides 1000 Newtons (100 kgf) of thrust and produces no flames or poisonous fumes. His first successful powered wingsuit jump was in 2007, when he reached horizontal speeds of over 255 km/h (160 mph).

Electric wingsuit
In November 2020, professional BASE jumper Peter Salzmann completed the first electric wingsuit flight, using a wingsuit developed by BMW's BMW i division.

Wingpack
Another variation on which studies are being focused is the wingpack, which consists of a strap-on rigid wing made of carbon fibre.

Training
Flying a wingsuit can add considerable complexity to a skydive. According to the Skydivers' Information Manual, the United States Parachute Association requires that any jumper have a minimum of 200 freefall skydives before completing a wingsuit first jump course and making a wingsuit jump. Requirements in other nations are similar. Wingsuit manufacturers offer training courses and certify instructors, and also impose the minimum jump numbers required before purchasing a wingsuit. Wingsuit pilots start on smaller wingsuits with less surface area. With practice, pilots can learn to fly larger suits with more surface area, which allow for increased glide and airtime. Within the sport of wingsuit flying, there are many sub-disciplines that participants may pursue, including: acrobatic flying, performance flying, and wingsuit BASE jumping.

Wingsuit formation records
Fédération Aéronautique Internationale (FAI), the world governing airsports body, established judging criteria for official world record wingsuit formations in February 2015. The rules are available on the FAI website.

Prior to this, the largest wingsuit formation recognized as meeting the criteria for a national record consisted of 68 wingsuit pilots, which set a U.S. national record at Lake Elsinore, California, on 12 November 2009. The largest global record was a diamond formation involving 100 wingsuit pilots at Perris, California, on 22 September 2012. These records have since been retired as they do not meet the current rules.

Two World Records have been set since the rules update. A 42-person formation over Moorsele, Belgium, set an FAI record on 18 June 2015. This was broken on 17 October 2015, when 61 wingsuit pilots set the current FAI world record over Perris Valley Airport near Perris, California.

The current U.S. national record includes 43 wingsuit pilots. It was set on 5 October 2018 in Rosharon, Texas, at Skydive Spaceland-Houston.

Highest altitude
On 23 May 2006, the Australian couple Heather Swan and Glenn Singleman jumped from 6604 m off Meru Peak in India, setting a world record for highest wingsuit BASE jump. This record was broken on 5 May 2013, by the Russian Valery Rozov, who jumped from 7220 m on Mount Everest's North Col. Rozov broke his own record by jumping from 7700 m on Cho Oyu in 2016.

Longest
The longest verified wingsuit BASE jump is 7.5 km by the American Dean Potter on 2 November 2011. Potter jumped from the Eiger mountain and spent 3 minutes and 20 seconds in flight, descending 9200 ft of altitude.

Biggest
The biggest wingsuit BASE jump as measured from exit to landing was performed on 11 August 2013 by Patrick Kerber with a height of 3240 m off the Jungfrau in Switzerland.

Fastest
On 22 May 2017, British wingsuit pilot Fraser Corsan set world records for the fastest speed reached in a wingsuit of 396.86 km/h.

Greatest average horizontal speed
The current world record for greatest average horizontal speed within the performance competition rules, i.e. within 1000 meters of vertical distance, was set by Travis Mickle (US) with a speed of 325.4 km/h (202.19 mph) 6 November 2017. American Ellen Brennan is considered the fastest flying woman in the world.

Longest time
On 20 and 21 April 2012, Colombian skydiver Jhonathan Florez set Guinness World Records in wingsuit flying. The jumps took place in La Guajira in Colombia. The longest (duration) wingsuit flight was 9 minutes, 6 seconds

The current world record for longest time in flight within the performance competition rules, i.e. within 1000 meters of vertical distance, was set on 28 Aug 2018 by Chris Geiler (US) with a time of 100.2 sec (1.67 min)

Highest altitude
The highest altitude wingsuit jump is 13183.70 meters, and was achieved by Aaron Smith above Whiteville, Tennessee, US, on 1 July 2023.

Farthest
, the Guinness World Record for "greatest absolute distance flown in a wing suit" is 32.094 km (19.94 mi) set by Kyle Lobpries (US) in Davis, California, on 30 May 2016.

The current world record for longest horizontal distance covered within the performance competition rules, i.e. within 1000 meters of vertical distance, was set on 27 May 2017 by U.S. wingsuit pilot Alexey Galda with a distance of 5.137 km (3.19 mi)

Highest Flare
The highest recorded flare ever achieved so far is 130.9 m (429.5ft) in altitude from lowest to highest point, set by Daniel Ossio (CH) in Piotrków Trybunalski, Poland on 03 May 2022.

The flare was made after exiting a tail gate aircraft at high speed.

Highest Flare (conventional)
The highest conventional flare ever made so far is 124.3 m (407.8ft) performed by Luke Rogers (AUS), performed in Ramblers, Australia on 9 September 2018.

The flare was made after diving and accelerating the wingsuit from altitude.

Landing
On 23 May 2012, British stuntman Gary Connery safely landed a wingsuit without deploying his parachute, landing on a crushable "runway" (landing zone) built with thousands of cardboard boxes.

Safety
Despite training and regulation, wingsuit BASE jumping remains a dangerous pastime, and fatalities occur regularly. A 2012 University of Colorado study found that in wingsuit BASE jumping, there was approximately one severe injury for every 500 jumps undertaken.

A detailed study on wingsuit deaths completed primarily by the University of Colorado found that out of 180 studied fatalities, 97% launched from cliffs and another 1% from buildings. The vast majority of these deaths were related to the use of the wingsuit, not to do with external sources. This makes aircraft descending a much less deadly form of wingsuit flying, though deemed less extreme by fans of the sport.

Legality
Some concerns regarding the nature of wingsuit flying exist due to injuries and death. The French government banned wingsuit flying multiple times following deaths from the activity.

title: Wingsuit flying


text:
User:Cygnus~enwiki

Name: Cygnus

Became a Wikipedian on: Sometime in 2003 I saw this site since then I have spend hours wandering about this site generally; but at times editing too

Crazy about: Everything under the sun and over it. Latest craze is wikipedia though.

title: User:Cygnus~enwiki


text:
Solar radius

Solar radius is a unit of distance used to express the size of stars in astronomy relative to the Sun. The solar radius is usually defined as the radius to the layer in the Sun's photosphere where the optical depth equals 2/3:

$$1\,R_{\odot} = 6.957\times 10^8 \hbox{ m} $$

695,700 km is approximately 10 times the average radius of Jupiter, 109 times the radius of the Earth, and 1/215th of an astronomical unit, the approximate distance between Earth and the Sun. The solar radius to either pole and that to the equator differ slightly due to the Sun's rotation, which induces an oblateness in the order of 10 parts per million.

Measurements
The uncrewed SOHO spacecraft was used to measure the radius of the Sun by timing transits of Mercury across the surface during 2003 and 2006. The result was a measured radius of 696342 +/-.

Haberreiter, Schmutz & Kosovichev (2008) determined the radius corresponding to the solar photosphere to be 695660 +/-. This new value is consistent with helioseismic estimates; the same study showed that previous estimates using inflection point methods had been overestimated by approximately 300 km.

Nominal solar radius
In 2015, the International Astronomical Union passed Resolution B3, which defined a set of nominal conversion constants for stellar and planetary astronomy. Resolution B3 defined the nominal solar radius (symbol $$R^{N}_{\odot}$$) to be equal to exactly $6.957$. The nominal value, which is the rounded value, within the uncertainty, given by Haberreiter, Schmutz & Kosovichev (2008), was adopted to help astronomers avoid confusion when quoting stellar radii in units of the Sun's radius, even when future observations will likely refine the Sun's actual photospheric radius (which is currently only known to about an accuracy of ±$7.354$).

Examples
Solar radii as a unit are common when describing spacecraft moving close to the sun. Two spacecraft in the 2010s include:

 * Solar Orbiter (as close as $2.255$)
 * Parker Solar Probe (as close as $695,700 km$)

title: Solar radius