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Bohrium

Bohrium is a synthetic chemical element; it has symbol Bh and atomic number 107. It is named after Danish physicist Niels Bohr. As a synthetic element, it can be created in particle accelerators but is not found in nature. All known isotopes of bohrium are highly radioactive; the most stable known isotope is 270Bh with a half-life of approximately 2.4 minutes, though the unconfirmed 278Bh may have a longer half-life of about 11.5 minutes.

In the periodic table, it is a d-block transactinide element. It is a member of the 7th period and belongs to the group 7 elements as the fifth member of the 6d series of transition metals. Chemistry experiments have confirmed that bohrium behaves as the heavier homologue to rhenium in group 7. The chemical properties of bohrium are characterized only partly, but they compare well with the chemistry of the other group 7 elements.

Discovery
Two groups claimed discovery of the element. Evidence of bohrium was first reported in 1976 by a Soviet research team led by Yuri Oganessian, in which targets of bismuth-209 and lead-208 were bombarded with accelerated nuclei of chromium-54 and manganese-55 respectively. Two activities, one with a half-life of one to two milliseconds, and the other with an approximately five-second half-life, were seen. Since the ratio of the intensities of these two activities was constant throughout the experiment, it was proposed that the first was from the isotope bohrium-261 and that the second was from its daughter dubnium-257. Later, the dubnium isotope was corrected to dubnium-258, which indeed has a five-second half-life (dubnium-257 has a one-second half-life); however, the half-life observed for its parent is much shorter than the half-lives later observed in the definitive discovery of bohrium at Darmstadt in 1981. The IUPAC/IUPAP Transfermium Working Group (TWG) concluded that while dubnium-258 was probably seen in this experiment, the evidence for the production of its parent bohrium-262 was not convincing enough.

In 1981, a German research team led by Peter Armbruster and Gottfried Münzenberg at the GSI Helmholtz Centre for Heavy Ion Research (GSI Helmholtzzentrum für Schwerionenforschung) in Darmstadt bombarded a target of bismuth-209 with accelerated nuclei of chromium-54 to produce 5 atoms of the isotope bohrium-262:

This discovery was further substantiated by their detailed measurements of the alpha decay chain of the produced bohrium atoms to previously known isotopes of fermium and californium. The IUPAC/IUPAP Transfermium Working Group (TWG) recognised the GSI collaboration as official discoverers in their 1992 report.

Proposed names
In September 1992, the German group suggested the name nielsbohrium with symbol Ns to honor the Danish physicist Niels Bohr. The Soviet scientists at the Joint Institute for Nuclear Research in Dubna, Russia had suggested this name be given to element 105 (which was finally called dubnium) and the German team wished to recognise both Bohr and the fact that the Dubna team had been the first to propose the cold fusion reaction, and simultaneously help to solve the controversial problem of the naming of element 105. The Dubna team agreed with the German group's naming proposal for element 107.

There was an element naming controversy as to what the elements from 104 to 106 were to be called; the IUPAC adopted unnilseptium (symbol Uns) as a temporary, systematic element name for this element. In 1994 a committee of IUPAC recommended that element 107 be named bohrium, not nielsbohrium, since there was no precedent for using a scientist's complete name in the naming of an element. This was opposed by the discoverers as there was some concern that the name might be confused with boron and in particular the distinguishing of the names of their respective oxyanions, bohrate and borate. The matter was handed to the Danish branch of IUPAC which, despite this, voted in favour of the name bohrium, and thus the name bohrium for element 107 was recognized internationally in 1997; the names of the respective oxyanions of boron and bohrium remain unchanged despite their homophony.

Isotopes
Bohrium has no stable or naturally occurring isotopes. Several radioactive isotopes have been synthesized in the laboratory, either by fusing two atoms or by observing the decay of heavier elements. Twelve different isotopes of bohrium have been reported with atomic masses 260–262, 264–267, 270–272, 274, and 278, one of which, bohrium-262, has a known metastable state. All of these but the unconfirmed 278Bh decay only through alpha decay, although some unknown bohrium isotopes are predicted to undergo spontaneous fission.

The lighter isotopes usually have shorter half-lives; half-lives of under 100 ms for 260Bh, 261Bh, 262Bh, and 262mBh were observed. 264Bh, 265Bh, 266Bh, and 271Bh are more stable at around 1 s, and 267Bh and 272Bh have half-lives of about 10 s. The heaviest isotopes are the most stable, with 270Bh and 274Bh having measured half-lives of about 2.4 min and 40 s respectively, and the even heavier unconfirmed isotope 278Bh appearing to have an even longer half-life of about 11.5 minutes.

The most proton-rich isotopes with masses 260, 261, and 262 were directly produced by cold fusion, those with mass 262 and 264 were reported in the decay chains of meitnerium and roentgenium, while the neutron-rich isotopes with masses 265, 266, 267 were created in irradiations of actinide targets. The five most neutron-rich ones with masses 270, 271, 272, 274, and 278 (unconfirmed) appear in the decay chains of 282Nh, 287Mc, 288Mc, 294Ts, and 290Fl respectively. The half-lives of bohrium isotopes range from about ten milliseconds for 262mBh to about one minute for 270Bh and 274Bh, extending to about 11.5 minutes for the unconfirmed 278Bh, which may have one of the longest half-lives among reported superheavy nuclides.

Predicted properties
Very few properties of bohrium or its compounds have been measured; this is due to its extremely limited and expensive production and the fact that bohrium (and its parents) decays very quickly. A few singular chemistry-related properties have been measured, but properties of bohrium metal remain unknown and only predictions are available.

Chemical
Bohrium is the fifth member of the 6d series of transition metals and the heaviest member of group 7 in the periodic table, below manganese, technetium and rhenium. All the members of the group readily portray their group oxidation state of +7 and the state becomes more stable as the group is descended. Thus bohrium is expected to form a stable +7 state. Technetium also shows a stable +4 state whilst rhenium exhibits stable +4 and +3 states. Bohrium may therefore show these lower states as well. The higher +7 oxidation state is more likely to exist in oxyanions, such as perbohrate,, analogous to the lighter permanganate, pertechnetate, and perrhenate. Nevertheless, bohrium(VII) is likely to be unstable in aqueous solution, and would probably be easily reduced to the more stable bohrium(IV).

The lighter group 7 elements are known to form volatile heptoxides M2O7 (M = Mn, Tc, Re), so bohrium should also form the volatile oxide Bh2O7. The oxide should dissolve in water to form perbohric acid, HBhO4. Rhenium and technetium form a range of oxyhalides from the halogenation of the oxide. The chlorination of the oxide forms the oxychlorides MO3Cl, so BhO3Cl should be formed in this reaction. Fluorination results in MO3F and MO2F3 for the heavier elements in addition to the rhenium compounds ReOF5 and ReF7. Therefore, oxyfluoride formation for bohrium may help to indicate eka-rhenium properties. Since the oxychlorides are asymmetrical, and they should have increasingly large dipole moments going down the group, they should become less volatile in the order TcO3Cl > ReO3Cl > BhO3Cl: this was experimentally confirmed in 2000 by measuring the enthalpies of adsorption of these three compounds. The values are for TcO3Cl and ReO3Cl are −51 kJ/mol and −61 kJ/mol respectively; the experimental value for BhO3Cl is −77.8 kJ/mol, very close to the theoretically expected value of −78.5 kJ/mol.

Physical and atomic
Bohrium is expected to be a solid under normal conditions and assume a hexagonal close-packed crystal structure (c/a = 1.62), similar to its lighter congener rhenium. Early predictions by Fricke estimated its density at 37.1 g/cm3, but newer calculations predict a somewhat lower value of 26–27 g/cm3.

The atomic radius of bohrium is expected to be around 128 pm. Due to the relativistic stabilization of the 7s orbital and destabilization of the 6d orbital, the Bh+ ion is predicted to have an electron configuration of [Rn] 5f14 6d4 7s2, giving up a 6d electron instead of a 7s electron, which is the opposite of the behavior of its lighter homologues manganese and technetium. Rhenium, on the other hand, follows its heavier congener bohrium in giving up a 5d electron before a 6s electron, as relativistic effects have become significant by the sixth period, where they cause among other things the yellow color of gold and the low melting point of mercury. The Bh2+ ion is expected to have an electron configuration of [Rn] 5f14 6d3 7s2; in contrast, the Re2+ ion is expected to have a [Xe] 4f14 5d5 configuration, this time analogous to manganese and technetium. The ionic radius of hexacoordinate heptavalent bohrium is expected to be 58 pm (heptavalent manganese, technetium, and rhenium having values of 46, 57, and 53 pm respectively). Pentavalent bohrium should have a larger ionic radius of 83 pm.

Experimental chemistry
In 1995, the first report on attempted isolation of the element was unsuccessful, prompting new theoretical studies to investigate how best to investigate bohrium (using its lighter homologs technetium and rhenium for comparison) and removing unwanted contaminating elements such as the trivalent actinides, the group 5 elements, and polonium.

In 2000, it was confirmed that although relativistic effects are important, bohrium behaves like a typical group 7 element. A team at the Paul Scherrer Institute (PSI) conducted a chemistry reaction using six atoms of 267Bh produced in the reaction between 249Bk and 22Ne ions. The resulting atoms were thermalised and reacted with a HCl/O2 mixture to form a volatile oxychloride. The reaction also produced isotopes of its lighter homologues, technetium (as 108Tc) and rhenium (as 169Re). The isothermal adsorption curves were measured and gave strong evidence for the formation of a volatile oxychloride with properties similar to that of rhenium oxychloride. This placed bohrium as a typical member of group 7. The adsorption enthalpies of the oxychlorides of technetium, rhenium, and bohrium were measured in this experiment, agreeing very well with the theoretical predictions and implying a sequence of decreasing oxychloride volatility down group 7 of TcO3Cl > ReO3Cl > BhO3Cl.

 * 2 Bh + 3 + 2 HCl → 2  +

The longer-lived heavy isotopes of bohrium, produced as the daughters of heavier elements, offer advantages for future radiochemical experiments. Although the heavy isotope 274Bh requires a rare and highly radioactive berkelium target for its production, the isotopes 272Bh, 271Bh, and 270Bh can be readily produced as daughters of more easily produced moscovium and nihonium isotopes.

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title: Bohrium


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Barbara Olson

Barbara Kay Olson (née Bracher; December 27, 1955 – September 11, 2001) was an American lawyer and conservative television commentator who worked for CNN, Fox News Channel, and several other outlets. She was a passenger on American Airlines Flight 77 en route to a taping of Bill Maher's television show Politically Incorrect when it was flown into the Pentagon in the September 11 attacks.

Early life
Olson was born Barbara Kay Bracher in Houston, Texas, on December 27, 1955. Her older sister, Toni Bracher-Lawrence, was a member of the Houston City Council from 2004 to 2010. She graduated from Waltrip High School.

Personal life
She married Theodore Olson in 1996, becoming his third wife.

Olson was a frequent critic of the Bill Clinton administration and wrote a book about then First Lady Hillary Clinton, Hell to Pay: The Unfolding Story of Hillary Rodham Clinton (1999). Olson's second book, The Final Days: The Last, Desperate Abuses of Power by the Clinton White House was published posthumously.

Death and legacy
Olson was a passenger on American Airlines Flight 77, on her way to a taping of Politically Incorrect in Los Angeles, when it was flown into the Pentagon in the September 11 attacks.

Her original plan had been to fly to California on September 10, but she waited until the next day so that she could wake up with her husband on his birthday, September 11. At the National September 11 Memorial, Olson's name is located on Panel S-70 of the South Pool, along with those of other passengers of Flight 77.

Three months after the attacks, Olson's remains were identified. She was buried at her family's retreat in Wisconsin.

In popular culture

 * Canadian actress Marsha Mason portrayed Barbara Olson in the Canadian TV series Mayday Season 16: Episode 2 (2016) called "9/11: The Pentagon Attack" and Air Crash Investigation Special Report Season 2: Episode 1 (2019) called "Headline News".

title: Barbara Olson


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Barnard's Star

Barnard's Star is a small red dwarf star in the constellation of Ophiuchus. At a distance of 5.96 ly from Earth, it is the fourth-nearest-known individual star to the Sun after the three components of the Alpha Centauri system, and is the closest star in the northern celestial hemisphere. Its stellar mass is about 16% of the Sun's, and it has 19% of the Sun's diameter. Despite its proximity, the star has a dim apparent visual magnitude of +9.5 and is invisible to the unaided eye; it is much brighter in the infrared than in visible light.

The star is named after Edward Emerson Barnard, an American astronomer who in 1916 measured its proper motion as 10.3 arcseconds per year relative to the Sun, the highest known for any star. The star had previously appeared on Harvard University photographic plates in 1888 and 1890.

Barnard's Star is among the most studied red dwarfs because of its proximity and favorable location for observation near the celestial equator. Historically, research on Barnard's Star has focused on measuring its stellar characteristics, its astrometry, and also refining the limits of possible extrasolar planets. Although Barnard's Star is ancient, it still experiences stellar flare events, one being observed in 1998.

Barnard's Star has been subject to multiple claims of planets that were later disproven. From the early 1960s to the early 1970s, Peter van de Kamp argued that planets orbited Barnard's Star. His specific claims of large gas giants were refuted in the mid-1970s after much debate. In November 2018, a candidate super-Earth planetary companion known as Barnard's Star b was reported to orbit Barnard's Star. It was believed to have a minimum mass of and orbit at $−110.47$. However, work presented in July 2021 refuted the existence of this planet.

Naming
In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN) to catalogue and standardize proper names for stars. The WGSN approved the name Barnard's Star for this star on 1 February 2017 and it is now included in the List of IAU-approved Star Names.

Description
Barnard's Star is a red dwarf of the dim spectral type M4, and it is too faint to see without a telescope; Its apparent magnitude is 9.5.

At 7–12 billion years of age, Barnard's Star is considerably older than the Sun, which is 4.5 billion years old, and it might be among the oldest stars in the Milky Way galaxy. Barnard's Star has lost a great deal of rotational energy, and the periodic slight changes in its brightness indicate that it rotates once in 130 days (the Sun rotates in 25). Given its age, Barnard's Star was long assumed to be quiescent in terms of stellar activity. In 1998, astronomers observed an intense stellar flare, showing that Barnard's Star is a flare star. Barnard's Star has the variable star designation V2500 Ophiuchi. In 2003, Barnard's Star presented the first detectable change in the radial velocity of a star caused by its motion. Further variability in the radial velocity of Barnard's Star was attributed to its stellar activity.

The proper motion of Barnard's Star corresponds to a relative lateral speed of 90km/s. The 10.3 arcseconds it travels in a year amount to a quarter of a degree in a human lifetime, roughly half the angular diameter of the full Moon.

The radial velocity of Barnard's Star is $0.161$, as measured from the blueshift due to its motion toward the Sun. Combined with its proper motion and distance, this gives a "space velocity" (actual speed relative to the Sun) of $0.187$. Barnard's Star will make its closest approach to the Sun around 11,800 CE, when it will approach to within about 3.75 light-years.

Proxima Centauri is the closest star to the Sun at a position currently 4.24 light-years distant from it. However, despite Barnard's Star's even closer pass to the Sun in 11,800 CE, it will still not then be the nearest star, since by that time Proxima Centauri will have moved to a yet-nearer proximity to the Sun. At the time of the star's closest pass by the Sun, Barnard's Star will still be too dim to be seen with the naked eye, since its apparent magnitude will only have increased by one magnitude to about 8.5 by then, still being 2.5 magnitudes short of visibility to the naked eye.

Barnard's Star has a mass of about 0.16 solar masses, and a radius about 0.2 times that of the Sun. Thus, although Barnard's Star has roughly 150 times the mass of Jupiter, its radius is only roughly 2 times larger, due to its much higher density. Its effective temperature is about 3,220 kelvin, and it has a luminosity of only 0.0034 solar luminosities. Barnard's Star is so faint that if it were at the same distance from Earth as the Sun is, it would appear only 100 times brighter than a full moon, comparable to the brightness of the Sun at 80 astronomical units.

Barnard's Star has 10–32% of the solar metallicity. Metallicity is the proportion of stellar mass made up of elements heavier than helium and helps classify stars relative to the galactic population. Barnard's Star seems to be typical of the old, red dwarf population II stars, yet these are also generally metal-poor halo stars. While sub-solar, Barnard's Star's metallicity is higher than that of a halo star and is in keeping with the low end of the metal-rich disk star range; this, plus its high space motion, have led to the designation "intermediate population II star", between a halo and disk star. However, some recently published scientific papers have given much higher estimates for the metallicity of the star, very close to the Sun's level, between 75 and 125% of the solar metallicity.

Astrometric planetary claims
For a decade from 1963 to about 1973, a substantial number of astronomers accepted a claim by Peter van de Kamp that he had detected, by using astrometry, a perturbation in the proper motion of Barnard's Star consistent with its having one or more planets comparable in mass with Jupiter. Van de Kamp had been observing the star from 1938, attempting, with colleagues at the Sproul Observatory at Swarthmore College, to find minuscule variations of one micrometre in its position on photographic plates consistent with orbital perturbations that would indicate a planetary companion; this involved as many as ten people averaging their results in looking at plates, to avoid systemic individual errors. Van de Kamp's initial suggestion was a planet having about at a distance of 4.4AU in a slightly eccentric orbit, and these measurements were apparently refined in a 1969 paper. Later that year, Van de Kamp suggested that there were two planets of 1.1 and.

Other astronomers subsequently repeated Van de Kamp's measurements, and two papers in 1973 undermined the claim of a planet or planets. George Gatewood and Heinrich Eichhorn, at a different observatory and using newer plate measuring techniques, failed to verify the planetary companion. Another paper published by John L. Hershey four months earlier, also using the Swarthmore observatory, found that changes in the astrometric field of various stars correlated to the timing of adjustments and modifications that had been carried out on the refractor telescope's objective lens; the claimed planet was attributed to an artifact of maintenance and upgrade work. The affair has been discussed as part of a broader scientific review.

Van de Kamp never acknowledged any error and published a further claim of two planets' existence as late as 1982; he died in 1995. Wulff Heintz, Van de Kamp's successor at Swarthmore and an expert on double stars, questioned his findings and began publishing criticisms from 1976 onwards. The two men were reported to have become estranged because of this.

Barnard's Star b
In November 2018, an international team of astronomers announced the detection by radial velocity of a candidate super-Earth orbiting in relatively close proximity to Barnard's Star. Led by Ignasi Ribas of Spain their work, conducted over two decades of observation, provided strong evidence of the planet's existence. However, the existence of the planet was refuted in 2021, because the radial velocity signal was found to originate from a stellar activity cycle, and a study in 2022 confirmed this result.

Dubbed Barnard's Star b, the planet was thought to be near the stellar system's snow line, which is an ideal spot for the icy accretion of proto-planetary material. It was thought to orbit at 0.4AU every 233 days and had a proposed minimum mass of. The planet would have most likely been frigid, with an estimated surface temperature of about -170 C, and lie outside Barnard Star's presumed habitable zone. Direct imaging of the planet and its tell-tale light signature would have been possible in the decade after its discovery. Further faint and unaccounted-for perturbations in the system suggested there may be a second planetary companion even farther out.

Refining planetary boundaries
For the more than four decades between van de Kamp's rejected claim and the eventual announcement of a planet candidate, Barnard's Star was carefully studied and the mass and orbital boundaries for possible planets were slowly tightened. M dwarfs such as Barnard's Star are more easily studied than larger stars in this regard because their lower masses render perturbations more obvious.

Null results for planetary companions continued throughout the 1980s and 1990s, including interferometric work with the Hubble Space Telescope in 1999. Gatewood was able to show in 1995 that planets with were impossible around Barnard's Star, in a paper which helped refine the negative certainty regarding planetary objects in general. In 1999, the Hubble work further excluded planetary companions of with an orbital period of less than 1,000 days (Jupiter's orbital period is 4,332 days), while Kuerster determined in 2003 that within the habitable zone around Barnard's Star, planets are not possible with an "M sin i" value greater than 7.5 times the mass of the Earth, or with a mass greater than 3.1 times the mass of Neptune (much lower than van de Kamp's smallest suggested value).

In 2013, a research paper was published that further refined planet mass boundaries for the star. Using radial velocity measurements, taken over a period of 25 years, from the Lick and Keck Observatories and applying Monte Carlo analysis for both circular and eccentric orbits, upper masses for planets out to 1,000-day orbits were determined. Planets above two Earth masses in orbits of less than 10 days were excluded, and planets of more than ten Earth masses out to a two-year orbit were also confidently ruled out. It was also discovered that the habitable zone of the star seemed to be devoid of roughly Earth-mass planets or larger, save for face-on orbits.

Even though this research greatly restricted the possible properties of planets around Barnard's Star, it did not rule them out completely as terrestrial planets were always going to be difficult to detect. NASA's Space Interferometry Mission, which was to begin searching for extrasolar Earth-like planets, was reported to have chosen Barnard's Star as an early search target, however the mission was shut down in 2010. ESA's similar Darwin interferometry mission had the same goal, but was stripped of funding in 2007.

The analysis of radial velocities that eventually led to discovery of the candidate super-Earth orbiting Barnard's Star was also used to set more precise upper mass limits for possible planets, up to and within the habitable zone: a maximum of up to the inner edge and  on the outer edge of the optimistic habitable zone, corresponding to orbital periods of up to 10 and 40 days respectively. Therefore, it appears that Barnard's Star indeed does not host Earth-mass planets or larger, in hot and temperate orbits, unlike other M-dwarf stars that commonly have these types of planets in close-in orbits.

1998
In 1998 a stellar flare on Barnard's Star was detected based on changes in the spectral emissions on 17 July during an unrelated search for variations in the proper motion. Four years passed before the flare was fully analyzed, at which point it was suggested that the flare's temperature was 8,000K, more than twice the normal temperature of the star. Given the essentially random nature of flares, Diane Paulson, one of the authors of that study, noted that "the star would be fantastic for amateurs to observe".

The flare was surprising because intense stellar activity is not expected in stars of such age. Flares are not completely understood, but are believed to be caused by strong magnetic fields, which suppress plasma convection and lead to sudden outbursts: strong magnetic fields occur in rapidly rotating stars, while old stars tend to rotate slowly. For Barnard's Star to undergo an event of such magnitude is thus presumed to be a rarity. Research on the star's periodicity, or changes in stellar activity over a given timescale, also suggest it ought to be quiescent; 1998 research showed weak evidence for periodic variation in the star's brightness, noting only one possible starspot over 130 days.

Stellar activity of this sort has created interest in using Barnard's Star as a proxy to understand similar stars. It is hoped that photometric studies of its X-ray and UV emissions will shed light on the large population of old M dwarfs in the galaxy. Such research has astrobiological implications: given that the habitable zones of M dwarfs are close to the star, any planet located therein would be strongly affected by solar flares, stellar winds, and plasma ejection events.

2019
In 2019, two additional ultraviolet stellar flares were detected, each with far-ultraviolet energy of 3×1022 joules, together with one X-ray stellar flare with energy 1.6×1022 joules. The flare rate observed to date is enough to cause loss of 87 Earth atmospheres per billion years through thermal processes and ≈3 Earth atmospheres per billion years through ion loss processes on Barnard's Star b.

Environment

Barnard's Star shares much the same neighborhood as the Sun. The neighbors of Barnard's Star are generally of red dwarf size, the smallest and most common star type. Its closest neighbor is currently the red dwarf Ross 154, at a distance of 1.66 parsecs (5.41 light-years). The Sun and Alpha Centauri are, respectively, the next closest systems. From Barnard's Star, the Sun would appear on the diametrically opposite side of the sky at coordinates RA=5:57:48.5, Dec=−04°41′36″, in the westernmost part of the constellation Monoceros. The absolute magnitude of the Sun is 4.83, and at a distance of 1.834 parsecs, it would be a first-magnitude star, as Pollux is from the Earth.

Project Daedalus
Barnard's Star was studied as part of Project Daedalus. Undertaken between 1973 and 1978, the study suggested that rapid, uncrewed travel to another star system was possible with existing or near-future technology. Barnard's Star was chosen as a target partly because it was believed to have planets.

The theoretical model suggested that a nuclear pulse rocket employing nuclear fusion (specifically, electron bombardment of deuterium and helium-3) and accelerating for four years could achieve a velocity of 12% of the speed of light. The star could then be reached in 50 years, within a human lifetime. Along with detailed investigation of the star and any companions, the interstellar medium would be examined and baseline astrometric readings performed.

The initial Project Daedalus model sparked further theoretical research. In 1980, Robert Freitas suggested a more ambitious plan: a self-replicating spacecraft intended to search for and make contact with extraterrestrial life. Built and launched in Jupiter's orbit, it would reach Barnard's Star in 47 years under parameters similar to those of the original Project Daedalus. Once at the star, it would begin automated self-replication, constructing a factory, initially to manufacture exploratory probes and eventually to create a copy of the original spacecraft after 1,000 years.

title: Barnard's Star


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Bayer designation

A Bayer designation is a stellar designation in which a specific star is identified by a Greek or Latin letter followed by the genitive form of its parent constellation's Latin name. The original list of Bayer designations contained 1,564 stars. The brighter stars were assigned their first systematic names by the German astronomer Johann Bayer in 1603, in his star atlas Uranometria. Bayer catalogued only a few stars too far south to be seen from Germany, but later astronomers (including Nicolas-Louis de Lacaille and Benjamin Apthorp Gould) supplemented Bayer's catalog with entries for southern constellations.

Scheme
Bayer assigned a lowercase Greek letter (alpha (α), beta (β), gamma (γ), etc.) or a Latin letter (A, b, c, etc.) to each star he catalogued, combined with the Latin name of the star's parent constellation in genitive (possessive) form. The constellation name is frequently abbreviated to a standard three-letter form. For example, Aldebaran in the constellation Taurus (the Bull) is designated α Tauri (abbreviated α Tau, pronounced Alpha Tauri), which means "Alpha of the Bull".

Bayer used Greek letters for the brighter stars, but the Greek alphabet has only twenty-four letters, while a single constellation may contain fifty or more stars visible to the naked eye. When the Greek letters ran out, Bayer continued with Latin letters: uppercase A, followed by lowercase b through z (omitting j and v, but o was included), for a total of another 24 letters.

Bayer did not label "permanent" stars with uppercase letters (except for A, which he used instead of a to avoid confusion with α). However, a number of stars in southern constellations have uppercase letter designations, like B Centauri and G Scorpii. These letters were assigned by later astronomers, notably Lacaille in his Coelum Australe Stelliferum and Gould in his Uranometria Argentina. Lacaille followed Bayer's use of Greek letters, but this was insufficient for many constellations. He used first the lowercase letters, starting with a, and if needed the uppercase letters, starting with A, thus deviating somewhat from Bayer's practice. Lacaille used the Latin alphabet three times over in the large constellation Argo Navis, once for each of the three areas that are now the constellations of Carina, Puppis and Vela. That was still insufficient for the number of stars, so he also used uppercase Latin letters such as N Velorum and Q Puppis. Lacaille assigned uppercase letters between R and Z in several constellations, but these have either been dropped to allow the assignment of those letters to variable stars or have actually turned out to be variable.

Order by magnitude class
In most constellations, Bayer assigned Greek and Latin letters to stars within a constellation in rough order of apparent brightness, from brightest to dimmest. The order is not necessarily a precise labeling from brightest to dimmest: in Bayer's day stellar brightness could not be measured precisely. Instead, stars were traditionally assigned to one of six magnitude classes (the brightest to first magnitude, the dimmest to sixth), and Bayer typically ordered stars within a constellation by class: all the first-magnitude stars (in some order), followed by all the second-magnitude stars, and so on. Within each magnitude class, Bayer made no attempt to arrange stars by relative brightness. As a result, the brightest star in each class did not always get listed first in Bayer's order—and the brightest star overall did not necessarily get the designation "Alpha". A good example is the constellation Gemini, where Pollux is Beta Geminorum and the slightly dimmer Castor is Alpha Geminorum.

In addition, Bayer did not always follow the magnitude class rule; he sometimes assigned letters to stars according to their location within a constellation, or the order of their rising, or to historical or mythological details. Occasionally the order looks quite arbitrary.

Of the 88 modern constellations, there are at least 30 in which Alpha is not the brightest star, and four of those lack a star labeled "Alpha" altogether. The constellations with no Alpha-designated star include Vela and Puppis—both formerly part of Argo Navis, whose Greek-letter stars were split among three constellations. Canopus, the former α Argus, is now α Carinae in the modern constellation Carina. Norma's Alpha and Beta were reassigned to Scorpius and re-designated N and H Scorpii respectively, leaving Norma with no Alpha. Francis Baily died before designating an Alpha in Leo Minor, so it also has no Alpha. (The star 46 Leonis Minoris would have been the obvious candidate.)

Orion as an example
In Orion, Bayer first designated Betelgeuse and Rigel, the two 1st-magnitude stars (those of magnitude 1.5 or less), as Alpha and Beta from north to south, with Betelgeuse (the shoulder) coming ahead of Rigel (the foot), even though the latter is usually the brighter. (Betelgeuse is a variable star and can at its maximum occasionally outshine Rigel.) Bayer then repeated the procedure for the stars of the 2nd magnitude, labeling them from gamma through zeta in "top-down" (north-to-south) order. Letters as far as Latin p were used for stars of the sixth magnitude.

Bayer's miscellaneous labels
Although Bayer did not use uppercase Latin letters (except A) for "fixed stars", he did use them to label other items shown on his charts, such as neighboring constellations, "temporary stars", miscellaneous astronomical objects, or reference lines like the Tropic of Cancer. In Cygnus, for example, Bayer's fixed stars run through g, and on this chart Bayer employs H through P as miscellaneous labels, mostly for neighboring constellations. Bayer did not intend such labels as catalog designations, but some have survived to refer to astronomical objects: P Cygni for example is still used as a designation for Nova Cyg 1600. Tycho's Star (SN 1572), another "temporary star", appears as B Cassiopeiae. In charts for constellations that did not exhaust the Greek letters, Bayer sometimes used the leftover Greek letters for miscellaneous labels as well.

Revised designations
Ptolemy designated four stars as "border stars", each shared by two constellations: Alpheratz (in Andromeda and Pegasus), Elnath (in Taurus and Auriga), Nu Boötis (Nu1 and Nu2)(in Boötes and Hercules) and Fomalhaut (in Piscis Austrinus and Aquarius). Bayer assigned the first three of these stars a Greek letter from both constellations: Alpha Andromedae = Delta Pegasi, Beta Tauri = Gamma Aurigae, and Nu Boötis = Psi Herculis. (He catalogued Fomalhaut only once, as Alpha Piscis Austrini.) When the International Astronomical Union (IAU) assigned definite boundaries to the constellations in 1930, it declared that stars and other celestial objects can belong to only one constellation. Consequently, the redundant second designation in each pair above has dropped out of use.

Bayer assigned two stars duplicate names by mistake: Xi Arietis (duplicated as Psi Ceti) and Kappa Ceti (Kappa1 and Kappa2) (duplicated as g Tauri). He corrected these in a later atlas, and the duplicate names were no longer used.

Other cases of multiple Bayer designations arose when stars named by Bayer in one constellation were transferred by later astronomers to a different constellation. Bayer's Gamma and Omicron Scorpii, for example, were later reassigned from Scorpius to Libra and given the new names Sigma and Upsilon Librae. (To add to the confusion, the star now known as Omicron Scorpii was not named by Bayer but was assigned the designation o Scorpii (Latin lowercase 'o') by Lacaille—which later astronomers misinterpreted as omicron once Bayer's omicron had been reassigned to Libra.)

A few stars no longer lie (according to the modern constellation boundaries) within the constellation for which they are named. The proper motion of Rho Aquilae, for example, carried it across the boundary into Delphinus in 1992.

A further complication is the use of numeric superscripts to distinguish neighboring stars that Bayer (or a later astronomer) labeled with a common letter. Usually these are double stars (mostly optical doubles rather than true binary stars), but there are some exceptions such as the chain of stars π1, π2, π3, π4, π5 and π6 Orionis. The most stars given the same Bayer designation but with an extra number attached to it is Psi Aurigae. (ψ1, ψ2, ψ3, ψ4, ψ5, ψ6, ψ7, ψ8, ψ9, ψ10)

title: Bayer designation


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Boötes

Boötes is a constellation in the northern sky, located between 0° and +60° declination, and 13 and 16 hours of right ascension on the celestial sphere. The name comes from Boōtēs, which comes from Βοώτης 'herdsman' or 'plowman' (literally, 'ox-driver'; from βοῦς boûs 'cow').

One of the 48 constellations described by the 2nd-century astronomer Ptolemy, Boötes is now one of the 88 modern constellations. It contains the fourth-brightest star in the night sky, the orange giant Arcturus. Epsilon Boötis, or Izar, is a colourful multiple star popular with amateur astronomers. Boötes is home to many other bright stars, including eight above the fourth magnitude and an additional 21 above the fifth magnitude, making a total of 29 stars easily visible to the naked eye.

History and mythology
In ancient Babylon, the stars of Boötes were known as SHU.PA. They were apparently depicted as the god Enlil, who was the leader of the Babylonian pantheon and special patron of farmers. Boötes may have been represented by the animal foreleg constellation in ancient Egypt, resembling that of an ox sufficiently to have been originally proposed as the "foreleg of ox" by Berio.

Homer mentions Boötes in the Odyssey as a celestial reference for navigation, describing it as "late-setting" or "slow to set". Exactly whom Boötes is supposed to represent in Greek mythology is not clear. According to one version, he was a son of Demeter, Philomenus, twin brother of Plutus, a plowman who drove the oxen in the constellation Ursa Major. This agrees with the constellation's name. The ancient Greeks saw the asterism now called the "Big Dipper" or "Plough" as a cart with oxen. Some myths say that Boötes invented the plow and was memorialized for his ingenuity as a constellation.

Another myth associated with Boötes by Hyginus is that of Icarius, who was schooled as a grape farmer and winemaker by Dionysus. Icarius made wine so strong that those who drank it appeared poisoned, which caused shepherds to avenge their supposedly poisoned friends by killing Icarius. Maera, Icarius' dog, brought his daughter Erigone to her father's body, whereupon both she and the dog committed suicide. Zeus then chose to honor all three by placing them in the sky as constellations: Icarius as Boötes, Erigone as Virgo, and Maera as Canis Major or Canis Minor.

Following another reading, the constellation is identified with Arcas and also referred to as Arcas and Arcturus, son of Zeus and Callisto. Arcas was brought up by his maternal grandfather Lycaon, to whom one day Zeus went and had a meal. To verify that the guest was really the king of the gods, Lycaon killed his grandson and prepared a meal made from his flesh. Zeus noticed and became very angry, transforming Lycaon into a wolf and giving life back to his son. In the meantime Callisto had been transformed into a she-bear by Zeus's wife Hera, who was angry at Zeus's infidelity. This is corroborated by the Greek name for Boötes, Arctophylax, which means "Bear Watcher".

Callisto, in the form of a bear was almost killed by her son, who was out hunting. Zeus rescued her, taking her into the sky where she became Ursa Major, "the Great Bear". Arcturus, the name of the constellation's brightest star, comes from the Greek word meaning "guardian of the bear". Sometimes Arcturus is depicted as leading the hunting dogs of nearby Canes Venatici and driving the bears of Ursa Major and Ursa Minor.

Several former constellations were formed from stars now included in Boötes. Quadrans Muralis, the Quadrant, was a constellation created near Beta Boötis from faint stars. It was designated in 1795 by Jérôme Lalande, an astronomer who used a quadrant to perform detailed astronometric measurements. Lalande worked with Nicole-Reine Lepaute and others to predict the 1758 return of Halley's Comet. Quadrans Muralis was formed from the stars of eastern Boötes, western Hercules and Draco. It was originally called Le Mural by Jean Fortin in his 1795 Atlas Céleste; it was not given the name Quadrans Muralis until Johann Bode's 1801 Uranographia. The constellation was quite faint, with its brightest stars reaching the 5th magnitude. Mons Maenalus, representing the Maenalus mountains, was created by Johannes Hevelius in 1687 at the foot of the constellation's figure. The mountain was named for the son of Lycaon, Maenalus. The mountain, one of Diana's hunting grounds, was also holy to Pan.

Non-Western astronomy
The stars of Boötes were incorporated into many different Chinese constellations. Arcturus was part of the most prominent of these, variously designated as the celestial king's throne (Tian Wang) or the Blue Dragon's horn (Daijiao); the name Daijiao, meaning "great horn", is more common. Arcturus was given such importance in Chinese celestial mythology because of its status marking the beginning of the lunar calendar, as well as its status as the brightest star in the northern night sky.

Two constellations flanked Daijiao: Yousheti to the right and Zuosheti to the left; they represented companions that orchestrated the seasons. Zuosheti was formed from modern Zeta, Omicron and Pi Boötis, while Yousheti was formed from modern Eta, Tau and Upsilon Boötis. Dixi, the Emperor's ceremonial banquet mat, was north of Arcturus, consisting of the stars 12, 11 and 9 Boötis. Another northern constellation was Qigong, the Seven Dukes, which mostly straddled the Boötes-Hercules border. It included either Delta Boötis or Beta Boötis as its terminus.

The other Chinese constellations made up of the stars of Boötes existed in the modern constellation's north; they are all representations of weapons. Tianqiang, the spear, was formed from Iota, Kappa and Theta Boötis; Genghe, variously representing a lance or shield, was formed from Epsilon, Rho and Sigma Boötis.

There were also two weapons made up of a singular star. Xuange, the halberd, was represented by Lambda Boötis, and Zhaoyao, either the sword or the spear, was represented by Gamma Boötis.

Two Chinese constellations have an uncertain placement in Boötes. Kangchi, the lake, was placed south of Arcturus, though its specific location is disputed. It may have been placed entirely in Boötes, on either side of the Boötes-Virgo border, or on either side of the Virgo-Libra border. The constellation Zhouding, a bronze tripod-mounted container used for food, was sometimes cited as the stars 1, 2 and 6 Boötis. However, it has also been associated with three stars in Coma Berenices.

Boötes is also known to Native American cultures. In Yup'ik language, Boötes is Taluyaq, literally "fish trap," and the funnel-shaped part of the fish trap is known as Ilulirat.

Characteristics
Boötes is a constellation bordered by Virgo to the south, Coma Berenices and Canes Venatici to the west, Ursa Major to the northwest, Draco to the northeast, and Hercules, Corona Borealis and Serpens Caput to the east. The three-letter abbreviation for the constellation, as adopted by the International Astronomical Union in 1922, is "Boo". The official constellation boundaries, as set by Belgian astronomer Eugène Delporte in 1930, are defined by a polygon of 16 segments. In the equatorial coordinate system, the right ascension coordinates of these borders lie between 13:36.1:0 and 15:49.3:0, while the declination coordinates stretch from +7.36° to +55.1°. Covering 907 square degrees, Boötes culminates at midnight around 2 May and ranks 13th in area.

Colloquially, its pattern of stars has been likened to a kite or ice cream cone. However, depictions of Boötes have varied historically. Aratus described him circling the north pole, herding the two bears. Later ancient Greek depictions, described by Ptolemy, have him holding the reins of his hunting dogs (Canes Venatici) in his left hand, with a spear, club, or staff in his right hand. After Hevelius introduced Mons Maenalus in 1681, Boötes was often depicted standing on the Peloponnese mountain. By 1801, when Johann Bode published his Uranographia, Boötes had acquired a sickle, which was also held in his left hand.

The placement of Arcturus has also been mutable through the centuries. Traditionally, Arcturus lay between his thighs, as Ptolemy depicted him. However, Germanicus Caesar deviated from this tradition by placing Arcturus "where his garment is fastened by a knot".

Stars
In his Uranometria, Johann Bayer used the Greek letters alpha through to omega and then A to k to label what he saw as the most prominent 35 stars in the constellation, with subsequent astronomers splitting Kappa, Mu, Nu and Pi as two stars each. Nu is also the same star as Psi Herculis. John Flamsteed numbered 54 stars for the constellation.

Located 36.7 light-years from Earth, Arcturus, or Alpha Boötis, is the brightest star in Boötes and the fourth-brightest star in the sky at an apparent magnitude of −0.05; It is also the brightest star north of the celestial equator, just shading out Vega and Capella. Its name comes from the Greek for "bear-keeper". An orange giant of spectral class K1.5III, Arcturus is an ageing star that has exhausted its core supply of hydrogen and cooled and expanded to a diameter of 27 solar diameters, equivalent to approximately 32 million kilometers. Though its mass is approximately one solar mass, Arcturus shines with 133 times the luminosity of the Sun.

Bayer located Arcturus above the Herdman's left knee in his Uranometria. Nearby Eta Boötis, or Muphrid, is the uppermost star denoting the left leg. It is a 2.68-magnitude star 37 light-years distant with a spectral class of G0IV, indicating it has just exhausted its core hydrogen and is beginning to expand and cool. It is 9 times as luminous as the Sun and has 2.7 times its diameter. Analysis of its spectrum reveals that it is a spectroscopic binary. Muphrid and Arcturus lie only 3.3 light-years away from each other. Viewed from Arcturus, Muphrid would have a visual magnitude of −2½, while Arcturus would be around visual magnitude −4½ when seen from Muphrid.

Marking the herdsman's head is Beta Boötis, or Nekkar, a yellow giant of magnitude 3.5 and spectral type G8IIIa. Like Arcturus, it has expanded and cooled off the main sequence—likely to have lived most of its stellar life as a blue-white B-type main sequence star. Its common name comes from the Arabic phrase for "ox-driver". It is 219 light-years away and has a luminosity of.

Located 86 light-years distant, Gamma Boötis, or Seginus, is a white giant star of spectral class A7III, with a luminosity 34 times and diameter 3.5 times that of the Sun. It is a Delta Scuti variable, ranging between magnitudes 3.02 and 3.07 every 7 hours. These stars are short period (six hours at most) pulsating stars that have been used as standard candles and as subjects to study asteroseismology.

Delta Boötis is a wide double star with a primary of magnitude 3.5 and a secondary of magnitude 7.8. The primary is a yellow giant that has cooled and expanded to 10.4 times the diameter of the Sun. Of spectral class G8IV, it is around 121 light-years away, while the secondary is a yellow main sequence star of spectral type G0V. The two are thought to take 120,000 years to orbit each other.

Mu Boötis, known as Alkalurops, is a triple star popular with amateur astronomers. It has an overall magnitude of 4.3 and is 121 light-years away. Its name is from the Arabic phrase for "club" or "staff". The primary appears to be of magnitude 4.3 and is blue-white. The secondary appears to be of magnitude 6.5, but is actually a close double star itself with a primary of magnitude 7.0 and a secondary of magnitude 7.6. The secondary and tertiary stars have an orbital period of 260 years. The primary has an absolute magnitude of 2.6 and is of spectral class F0. The secondary and tertiary stars are separated by 2 arcseconds; the primary and secondary are separated by 109.1 arcseconds at an angle of 171 degrees.

Nu Boötis is an optical double star. The primary is an orange giant of magnitude 5.0 and the secondary is a white star of magnitude 5.0. The primary is 870 light-years away and the secondary is 430 light-years.

Epsilon Boötis, also known as Izar or Pulcherrima, is a close triple star popular with amateur astronomers and the most prominent binary star in Boötes. The primary is a yellow- or orange-hued magnitude 2.5 giant star, the secondary is a magnitude 4.6 blue-hued main-sequence star, and the tertiary is a magnitude 12.0 star. The system is 210 light-years away. The name "Izar" comes from the Arabic word for "girdle" or "loincloth", referring to its location in the constellation. The name "Pulcherrima" comes from the Latin phrase for "most beautiful", referring to its contrasting colors in a telescope. The primary and secondary stars are separated by 2.9 arcseconds at an angle of 341 degrees; the primary's spectral class is K0 and it has a luminosity of. To the naked eye, Izar has a magnitude of 2.37.

Nearby Rho and Sigma Boötis denote the herdsman's waist. Rho is an orange giant of spectral type K3III located around 160 light-years from Earth. It is ever so slightly variable, wavering by 0.003 of a magnitude from its average of 3.57. Sigma, a yellow-white main-sequence star of spectral type F3V, is suspected of varying in brightness from 4.45 to 4.49. It is around 52 light-years distant.

Traditionally known as Aulād al Dhiʼbah (أولاد الضباع – aulād al dhiʼb), "the Whelps of the Hyenas", Theta, Iota, Kappa and Lambda Boötis (or Xuange ) are a small group of stars in the far north of the constellation. The magnitude 4.05 Theta Boötis has a spectral type of F7 and an absolute magnitude of 3.8. Iota Boötis is a triple star with a primary of magnitude 4.8 and spectral class of A7, a secondary of magnitude 7.5, and a tertiary of magnitude 12.6. The primary is 97 light-years away. The primary and secondary stars are separated by 38.5 arcseconds, at an angle of 33 degrees. The primary and tertiary stars are separated by 86.7 arcseconds at an angle of 194 degrees. Both the primary and tertiary appear white in a telescope, but the secondary appears yellow-hued.

Kappa Boötis is another wide double star. The primary is 155 light-years away and has a magnitude of 4.5. The secondary is 196 light-years away and has a magnitude of 6.6. The two components are separated by 13.4 arcseconds, at an angle of 236 degrees. The primary, with spectral class A7, appears white and the secondary appears bluish.

An apparent magnitude 4.18 type A0p star, Lambda Boötis is the prototype of a class of chemically peculiar stars, only some of which pulsate as Delta Scuti-type stars. The distinction between the Lambda Boötis stars as a class of stars with peculiar spectra, and the Delta Scuti stars whose class describes pulsation in low-overtone pressure modes, is an important one. While many Lambda Boötis stars pulsate and are Delta Scuti stars, not many Delta Scuti stars have Lambda Boötis peculiarities, since the Lambda Boötis stars are a much rarer class whose members can be found both inside and outside the Delta Scuti instability strip. Lambda Boötis stars are dwarf stars that can be either spectral class A or F. Like BL Boötis-type stars they are metal-poor. Scientists have had difficulty explaining the characteristics of Lambda Boötis stars, partly because only around 60 confirmed members exist, but also due to heterogeneity in the literature. Lambda has an absolute magnitude of 1.8.

There are two dimmer F-type stars, magnitude 4.83 12 Boötis, class F8; and magnitude 4.93 45 Boötis, class F5. Xi Boötis is a G8 yellow dwarf of magnitude 4.55, and absolute magnitude is 5.5. Two dimmer G-type stars are magnitude 4.86 31 Boötis, class G8, and magnitude 4.76 44 Boötis, class G0.

Of apparent magnitude 4.06, Upsilon Boötis has a spectral class of K5 and an absolute magnitude of −0.3. Dimmer than Upsilon Boötis is magnitude 4.54 Phi Boötis, with a spectral class of K2 and an absolute magnitude of −0.1. Just slightly dimmer than Phi at magnitude 4.60 is O Boötis, which, like Izar, has a spectral class of K0. O Boötis has an absolute magnitude of 0.2. The other four dim stars are magnitude 4.91 6 Boötis, class K4; magnitude 4.86 20 Boötis, class K3; magnitude 4.81 Omega Boötis, class K4; and magnitude 4.83 A Boötis, class K1.

There is one bright B-class star in Boötes; magnitude 4.93 Pi1 Boötis, also called Alazal. It has a spectral class of B9 and is 40 parsecs from Earth. There is also one M-type star, magnitude 4.81 34 Boötis. It is of class gM0.

Multiple stars
Besides Pulcherrima and Alkalurops, there are several other binary stars in Boötes:
 * Xi Boötis is a quadruple star popular with amateur astronomers. The primary is a yellow star of magnitude 4.7 and the secondary is an orange star of magnitude 6.8. The system is 22 light-years away and has an orbital period of 150 years. The primary and secondary have a separation of 6.7 arcseconds at an angle of 319 degrees. The tertiary is a magnitude 12.6 star (though it may be observed to be brighter) and the quaternary is a magnitude 13.6 star.
 * Pi Boötis is a close triple star. The primary is a blue-white star of magnitude 4.9, the secondary is a blue-white star of magnitude 5.8, and the tertiary is a star of magnitude 10.4. The primary and secondary components are separated by 5.6 arcseconds at an angle of 108 degrees; the primary and tertiary components are separated by 128 arcseconds at an angle of 128 degrees.
 * Zeta Boötis is a triple star that consists of a physical binary pair with an optical companion. Lying 205 light-years away from Earth, The physical pair has a period of 123.3 years and consists of a magnitude 4.5 and a magnitude 4.6 star. The two components are separated by 1.0 arcseconds at an angle of 303 degrees. The optical companion is of magnitude 10.9, separated by 99.3 arcseconds at an angle of 259 degrees. 44 Boötis is an eclipsing variable star. The primary is of variable magnitude and the secondary is of magnitude 6.2; they have an orbital period of 225 years. The components are separated by 1.0 arcsecond at an angle of 40 degrees.

44 Boötis (i Boötis) is a double variable star 42 light-years away. It has an overall magnitude of 4.8 and appears yellow to the naked eye. The primary is of magnitude 5.3 and the secondary is of magnitude 6.1; their orbital period is 220 years. The secondary is itself an eclipsing variable star with a range of 0.6 magnitudes; its orbital period is 6.4 hours. It is a W Ursae Majoris variable that ranges in magnitude from a minimum of 7.1 to a maximum of 6.5 every 0.27 days. Both stars are G-type stars. Another eclipsing binary star is ZZ Boötis, which has two F2-type components of almost equal mass, and ranges in magnitude from a minimum of 6.79 to a maximum of 7.44 over a period of 5.0 days.

Variable stars
Two of the brighter Mira-type variable stars in the constellation are R and S Boötis. Both are red giants that range greatly in magnitude—from 6.2 to 13.1 over 223.4 days, and 7.8 to 13.8 over a period of 270.7 days, respectively. Also red giants, V and W Boötis are semi-regular variable stars that range in magnitude from 7.0 to 12.0 over a period of 258 days, and magnitude 4.7 to 5.4 over 450 days, respectively.

BL Boötis is the prototype of its class of pulsating variable stars, the anomalous Cepheids. These stars are somewhat similar to Cepheid variables, but they do not have the same relationship between their period and luminosity. Their periods are similar to RRAB variables; however, they are far brighter than these stars. BL Boötis is a member of the cluster NGC 5466. Anomalous Cepheids are metal poor and have masses not much larger than the Sun's, on average,. BL Boötis type stars are a subtype of RR Lyrae variables.

T Boötis was a nova observed in April 1860 at a magnitude of 9.7. It has never been observed since, but that does not preclude the possibility of it being a highly irregular variable star or a recurrent nova.

Stars with planetary systems

Extrasolar planets have been discovered encircling ten stars in Boötes as of 2012. Tau Boötis is orbited by a large planet, discovered in 1999. The host star itself is a magnitude 4.5 star of type F7V, 15.6 parsecs from Earth. It has a mass of and a radius of 1.331 solar radii ; a companion, GJ527B, orbits at a distance of 240 AU. Tau Boötis b, the sole planet discovered in the system, orbits at a distance of 0.046 AU every 3.31 days. Discovered through radial velocity measurements, it has a mass of 5.95 Jupiter masses. This makes it a hot Jupiter. The host star and planet are tidally locked, meaning that the planet's orbit and the star's particularly high rotation are synchronized. Furthermore, a slight variability in the host star's light may be caused by magnetic interactions with the planet. Carbon monoxide is present in the planet's atmosphere. Tau Boötis b does not transit its star, rather, its orbit is inclined 46 degrees.

Like Tau Boötis b, HAT-P-4b is also a hot Jupiter. It is noted for orbiting a particularly metal-rich host star and being of low density. Discovered in 2007, HAT-P-4 b has a mass of and a radius of. It orbits every 3.05 days at a distance of 0.04 AU. HAT-P-4, the host star, is an F-type star of magnitude 11.2, 310 parsecs from Earth. It is larger than the Sun, with a mass of and a radius of.

Boötes is also home to multiple-planet systems. HD 128311 is the host star for a two-planet system, consisting of HD 128311 b and HD 128311 c, discovered in 2002 and 2005, respectively. HD 128311 b is the smaller planet, with a mass of ; it was discovered through radial velocity observations. It orbits at almost the same distance as Earth, at 1.099 AU; however, its orbital period is significantly longer at 448.6 days.

The larger of the two, HD 128311 c, has a mass of and was discovered in the same manner. It orbits every 919 days inclined at 50°, and is 1.76 AU from the host star. The host star, HD 128311, is a K0V-type star located 16.6 parsecs from Earth. It is smaller than the Sun, with a mass of and a radius of ; it also appears below the threshold of naked-eye visibility at an apparent magnitude of 7.51.

There are several single-planet systems in Boötes. HD 132406 is a Sun-like star of spectral type G0V with an apparent magnitude of 8.45, 231.5 light-years from Earth. It has a mass of and a radius of. The star is orbited by a gas giant, HD 132406 b, discovered in 2007. HD 132406 orbits 1.98 AU from its host star with a period of 974 days and has a mass of. The planet was discovered by the radial velocity method.

WASP-23 is a star with one orbiting planet, WASP-23 b. The planet, discovered by the transit method in 2010, orbits every 2.944 days very close to its Sun, at 0.0376 AU. It is smaller than Jupiter, at and. Its star is a K1V-type star of apparent magnitude 12.7, far below naked-eye visibility, and smaller than the Sun at and.

HD 131496 is also encircled by one planet, HD 131496 b. The star is of type K0 and is located 110 parsecs from Earth; it appears at a visual magnitude of 7.96. It is significantly larger than the Sun, with a mass of and a radius of 4.6 solar radii. Its one planet, discovered in 2011 by the radial velocity method, has a mass of ; its radius is as yet undetermined. HD 131496 b orbits at a distance of 2.09 AU with a period of 883 days.

Another single planetary system in Boötes is the HD 132563 system, a triple star system. The parent star, technically HD 132563B, is a star of magnitude 9.47, 96 parsecs from Earth. It is almost exactly the size of the Sun, with the same radius and a mass only 1% greater. Its planet, HD 132563B b, was discovered in 2011 by the radial velocity method. , it orbits 2.62 AU from its star with a period of 1544 days. Its orbit is somewhat elliptical, with an eccentricity of 0.22. HD 132563B b is one of very few planets found in triple star systems; it orbits the isolated member of the system, which is separated from the other components, a spectroscopic binary, by 400 AU.

Also discovered through the radial velocity method, albeit a year earlier, is HD 136418 b, a two-Jupiter-mass planet that orbits the star HD 136418 at a distance of 1.32 AU with a period of 464.3 days. Its host star is a magnitude 7.88 G5-type star, 98.2 parsecs from Earth. It has a radius of and a mass of.

WASP-14 b is one of the most massive and dense exoplanets known, with a mass of and a radius of. Discovered via the transit method, it orbits 0.036 AU from its host star with a period of 2.24 days. WASP-14 b has a density of 4.6 grams per cubic centimeter, making it one of the densest exoplanets known. Its host star, WASP-14, is an F5V-type star of magnitude 9.75, 160 parsecs from Earth. It has a radius of and a mass of. It also has a very high proportion of lithium.

Deep-sky objects
Boötes is in a part of the celestial sphere facing away from the plane of our home Milky Way galaxy, and so does not have open clusters or nebulae. Instead, it has one bright globular cluster and many faint galaxies. The globular cluster NGC 5466 has an overall magnitude of 9.1 and a diameter of 11 arcminutes. It is a very loose globular cluster with fairly few stars and may appear as a rich, concentrated open cluster in a telescope. NGC 5466 is classified as a Shapley–Sawyer Concentration Class 12 cluster, reflecting its sparsity. Its fairly large diameter means that it has a low surface brightness, so it appears far dimmer than the catalogued magnitude of 9.1 and requires a large amateur telescope to view. Only approximately 12 stars are resolved by an amateur instrument.

Boötes has two bright galaxies. NGC 5248 (Caldwell 45) is a type Sc galaxy (a variety of spiral galaxy) of magnitude 10.2. It measures 6.5 by 4.9 arcminutes. Fifty million light-years from Earth, NGC 5248 is a member of the Virgo Cluster of galaxies; it has dim outer arms and obvious H II regions, dust lanes and young star clusters. NGC 5676 is another type Sc galaxy of magnitude 10.9. It measures 3.9 by 2.0 arcminutes. Other galaxies include NGC 5008, a type Sc emission-line galaxy, NGC 5548, a type S Seyfert galaxy, NGC 5653, a type S HII galaxy, NGC 5778 (also classified as NGC 5825), a type E galaxy that is the brightest of its cluster, NGC 5886, and NGC 5888, a type SBb galaxy. NGC 5698 is a barred spiral galaxy, notable for being the host of the 2005 supernova SN 2005bc, which peaked at magnitude 15.3.

Further away lies the 250-million-light-year-diameter Boötes void, a huge space largely empty of galaxies. Discovered by Robert Kirshner and colleagues in 1981, it is roughly 700 million light-years from Earth. Beyond it and within the bounds of the constellation, lie two superclusters at around 830 million and 1 billion light-years distant.

The Hercules–Corona Borealis Great Wall, the largest-known structure in the Universe, covers a significant part of Boötes.

Meteor showers
Boötes is home to the Quadrantid meteor shower, the most prolific annual meteor shower. It was discovered in January 1835 and named in 1864 by Alexander Herschel. The radiant is located in northern Boötes near Kappa Boötis, in its namesake former constellation of Quadrans Muralis. Quadrantid meteors are dim, but have a peak visible hourly rate of approximately 100 per hour on January 3–4. The zenithal hourly rate of the Quadrantids is approximately 130 meteors per hour at their peak; it is also a very narrow shower.

The Quadrantids are notoriously difficult to observe because of a low radiant and often inclement weather. The parent body of the meteor shower has been disputed for decades; however, Peter Jenniskens has proposed 2003 EH1, a minor planet, as the parent. 2003 EH1 may be linked to C/1490 Y1, a comet previously thought to be a potential parent body for the Quadrantids.

2003 EH1 is a short-period comet of the Jupiter family; 500 years ago, it experienced a catastrophic breakup event. It is now dormant. The Quadrantids had notable displays in 1982, 1985 and 2004. Meteors from this shower often appear to have a blue hue and travel at a moderate speed of 41.5–43 kilometers per second.

On April 28, 1984, a remarkable outburst of the normally placid Alpha Bootids was observed by visual observer Frank Witte from 00:00 to 2:30 UTC. In a 6 cm telescope, he observed 433 meteors in a field of view near Arcturus with a diameter of less than 1°. Peter Jenniskens comments that this outburst resembled a "typical dust trail crossing". The Alpha Bootids normally begin on April 14, peaking on April 27 and 28, and finishing on May 12. Its meteors are slow-moving, with a velocity of 20.9 kilometers per second. They may be related to Comet 73P/Schwassmann–Wachmann 3, but this connection is only theorized.

The June Bootids, also known as the Iota Draconids, is a meteor shower associated with the comet 7P/Pons–Winnecke, first recognized on May 27, 1916, by William F. Denning. The shower, with its slow meteors, was not observed prior to 1916 because Earth did not cross the comet's dust trail until Jupiter perturbed Pons–Winnecke's orbit, causing it to come within 0.03 AU of Earth's orbit the first year the June Bootids were observed.

In 1982, E. A. Reznikov discovered that the 1916 outburst was caused by material released from the comet in 1819. Another outburst of the June Bootids was not observed until 1998, because Comet Pons–Winnecke's orbit was not in a favorable position. However, on June 27, 1998, an outburst of meteors radiating from Boötes, later confirmed to be associated with Pons-Winnecke, was observed. They were incredibly long-lived, with trails of the brightest meteors lasting several seconds at times. Many fireballs, green-hued trails, and even some meteors that cast shadows were observed throughout the outburst, which had a maximum zenithal hourly rate of 200–300 meteors per hour.

Two Russian astronomers determined in 2002 that material ejected from the comet in 1825 was responsible for the 1998 outburst. Ejecta from the comet dating to 1819, 1825 and 1830 was predicted to enter Earth's atmosphere on June 23, 2004. The predictions of a shower less spectacular than the 1998 showing were borne out in a display that had a maximum zenithal hourly rate of 16–20 meteors per hour that night. The June Bootids are not expected to have another outburst in the next 50 years.

Typically, only 1–2 dim, very slow meteors are visible per hour; the average June Bootid has a magnitude of 5.0. It is related to the Alpha Draconids and the Bootids-Draconids. The shower lasts from June 27 to July 5, with a peak on the night of June 28. The June Bootids are classified as a class III shower (variable), and has an average entry velocity of 18 kilometers per second. Its radiant is located 7 degrees north of Beta Boötis.

The Beta Bootids is a weak shower that begins on January 5, peaks on January 16, and ends on January 18. Its meteors travel at 43 km/s. The January Bootids is a short, young meteor shower that begins on January 9, peaks from January 16 to January 18, and ends on January 18.

The Phi Bootids is another weak shower radiating from Boötes. It begins on April 16, peaks on April 30 and May 1, and ends on May 12. Its meteors are slow-moving, with a velocity of 15.1 km/s. They were discovered in 2006. The shower's peak hourly rate can be as high as six meteors per hour. Though named for a star in Boötes, the Phi Bootid radiant has moved into Hercules. The meteor stream is associated with three different asteroids: 1620 Geographos, 2062 Aten and 1978 CA.

The Lambda Bootids, part of the Bootid-Coronae Borealid Complex, are a weak annual shower with moderately fast meteors; 41.75 km/s. The complex includes the Lambda Bootids, as well as the Theta Coronae Borealids and Xi Coronae Borealids. All of the Bootid-Coronae Borealid showers are Jupiter family comet showers; the streams in the complex have highly inclined orbits.

There are several minor showers in Boötes, some of whose existence is yet to be verified. The Rho Bootids radiate from near the namesake star, and were hypothesized in 2010. The average Rho Bootid has an entry velocity of 43 km/s. It peaks in November and lasts for three days.

The Rho Bootid shower is part of the SMA complex, a group of meteor showers related to the Taurids, which is in turn linked to the comet 2P/Encke. However, the link to the Taurid shower remains unconfirmed and may be a chance correlation. Another such shower is the Gamma Bootids, which were hypothesized in 2006. Gamma Bootids have an entry velocity of 50.3 km/s. The Nu Bootids, hypothesized in 2012, have faster meteors, with an entry velocity of 62.8 km/s.

title: Boötes


text:
Bernardino Ochino

Bernardino Ochino (1487–1564) was an Italian, who was raised a Roman Catholic and later turned to Protestantism and became a Protestant reformer.

Biography
Bernardino Ochino was born in Siena, the son of the barber Domenico Ochino, and at the age of 7 or 8, in around 1504, was entrusted to the order of Franciscan Friars. From 1510 he studied medicine at Perugia.

Transfer to the Capuchins
At the age of 38, Ochino transferred himself in 1534 to the newly founded Order of Friars Minor Capuchin. By then he was the close friend of Juan de Valdés, Pietro Bembo, Vittoria Colonna, Pietro Martire, Carnesecchi. In 1538 he was elected vicar-general of his order. In 1539, urged by Bembo, he visited Venice and delivered a course of sermons showing a sympathy with justification by faith, which appeared more clearly in his Dialogues published the same year. He was suspected and denounced, but nothing ensued until the establishment of the Inquisition in Rome in June 1542, at the instigation of Cardinal Giovanni Pietro Carafa. Ochino received a citation to Rome, and set out to obey it about the middle of August. According to his own statement, he was deterred from presenting himself at Rome by the warnings of Cardinal Contarini, whom he found at Bologna, dying of poison administered by the reactionary party.

Escape to Geneva
Ochino turned aside to Florence, and after some hesitation went across the Alps to Geneva. He was cordially received by John Calvin, and published within two years several volumes of Prediche, controversial tracts rationalizing his change of religion. He also addressed replies to marchioness Vittoria Colonna, Claudio Tolomei, and other Italian sympathizers who were reluctant to go to the same length as himself. His own breach with the Roman Catholic Church was final.

Augsburg and England
In 1545 Ochino became minister of the Italian Protestant congregation at Augsburg. From this time dates his contact with Caspar Schwenckfeld. In 1546 he participated in the anti-Trinitarian Collegia Vicentina. He was compelled to flee from Augsburg when, in January 1547, the city was occupied by the imperial forces for the Diet of Augsburg.

Ochino found asylum in England, where he was made a prebendary of Canterbury Cathedral, received a pension from Edward VI's privy purse, and composed his major work, the Tragoedie or Dialoge of the unjuste usurped primacie of the Bishop of Rome. This text, originally written in Latin, is extant only in the 1549 translation of Bishop John Ponet. The form is a series of dialogues. Lucifer, enraged at the spread of Jesus's kingdom, convokes the fiends in council, and resolves to set up the pope as antichrist. The state, represented by the emperor Phocas, is persuaded to connive at the pope's assumption of spiritual authority; the other churches are intimidated into acquiescence; Lucifer's projects seem fully accomplished, when Heaven raises up Henry VIII of England and his son for their overthrow.

Several of Ochino's Prediche were translated into English by Anna Cooke; and he published numerous controversial treatises on the Continent. Ochino's Che Cosa è Christo was translated into Latin and English by the future Queen Elizabeth I of England in 1547.

Zürich
In 1553 the accession of Mary I drove Ochino from England. He went to Basel, where Lelio Sozzini and the lawyer Martino Muralto were sent to secure Ochino as pastor of the Italian church at Zürich, which Ochino accepted. The Italian congregation there was composed mainly of refugees from Locarno. There for 10 years Ochino wrote books which gave increasing evidence of his alienation from the orthodoxy around him. The most important of these was the Labyrinth, a discussion of the freedom of the will, covertly undermining the Calvinistic doctrine of predestination.

In 1563 a long simmering storm burst on Ochino with the publication of his Thirty Dialogues, in one of which his adversaries maintained that he had justified polygamy under the disguise of a pretended refutation. His dialogues on divorce and against the Trinity were also considered heretical.

Poland, and death
Ochino was not given opportunity to defend himself, and was banished from Zürich. After being refused admission by other Protestant cities, he directed his steps towards Poland, at that time the most tolerant state in Europe. He had not resided there long when an edict appeared (August 8, 1564) banishing all foreign dissidents. Fleeing the country, he encountered the plague at Pińczów; three of his four children were carried off; and he himself, worn out by misfortune, died in solitude and obscurity at Slavkov in Moravia, about the end of 1564.

Legacy
Ochino's reputation among Protestants was low. He was charged by Thomas Browne in 1643 with the authorship of the legendary-apocryphal heretical treatise De tribus Impostoribus, as well as with having carried his alleged approval of polygamy into practice.

His biographer Karl Benrath justified him, representing him as a fervent evangelist and at the same time as a speculative thinker with a passion for free inquiry. The picture is of Ochino always learning and unlearning and arguing out difficult questions with himself in his dialogues, frequently without attaining to any absolute conviction.

Works

 * Prediche (1542)
 * Epistola alli Signori di Balia della città di Siena (1543)
 * Responsio ad Marcum Brixiensem Abbatem Ordinis S. Benedicti (Geneva, 1543)
 * Responsio ad Mutium Justinopolitanum to Girolamo Muzio (1496-1576)
 * Tragoedie or Dialoge of the unjuste usurped primacie of the Bishop of Rome. 1549 translation of Bishop John Ponet.
 * Disputa intorno alla presenza del corpo di Cristo nel Sacramento della Cena
 * Labyrinth - Laberinti del libero arbitrio (1563) dedicated to Elisabeth I
 * Dialogi XXX (1563)
 * Prediche

title: Bernardino Ochino


text:
Bay of Quinte

The Bay of Quinte is a long, narrow bay shaped like the letter "Z" on the northern shore of Lake Ontario in the province of Ontario, Canada. It is just west of the head of the Saint Lawrence River that drains the Great Lakes into the Gulf of Saint Lawrence. It is located about 200 km east of Toronto and 350 km west of Montreal.

The name "Quinte" is derived from "Kenté" or Kentio, an Iroquoian village located near the south shore of the Bay. Later on, an early French Catholic mission was built at Kenté, located on the north shore of what is now Prince Edward County, leading to the Bay being named after the Mission. Officially, in the Mohawk language, the community is called Kenhtèːke, which means "the place of the bay". The Cayuga name is Tayędaːneːgęˀ or Detgayęːdaːnegęˀ, "land of two logs."

The Bay, as it is known locally, provides some of the best trophy walleye angling in North America as well as most sport fish common to the great lakes. The bay is subject to algal blooms in late summer. Zebra mussels as well as the other invasive species found in the Great Lakes are present.

The Quinte area played a vital role in bootlegging during prohibition in the United States, with large volumes of liquor being produced in the area, and shipped via boat on the bay to Lake Ontario finally arriving in New York State where it was distributed. Illegal sales of liquor accounted for many fortunes in and around Belleville.

Tourism in the area is significant, especially in the summer months due to the Bay of Quinte and its fishing, local golf courses, provincial parks, and wineries.

Geography
The northern side of the bay is defined by Ontario's mainland, while the southern side follows the shore of the Prince Edward County headland. Beginning in the east with the outlet to Lake Ontario, the bay runs west-southwest for 25 km to Picton (although this section is also called Adolphus Reach), where it turns north-northwest for another 20 km as far as Deseronto. From there it turns south-southwest again for another 40 km, running past Big Island on the south and Belleville on the north. The width of the bay rarely exceeds 2 km. The bay ends at Trenton (Quinte West) and the Trent River, both also on the north side. The Murray Canal has been cut through the "Carrying Place", the few kilometres separating the end of the bay and Lake Ontario on the west side. The Trent River is part of the Trent-Severn Waterway, a canal connecting Lake Ontario to Lake Simcoe and then Georgian Bay on Lake Huron.

There are several sub-bays off the Bay of Quinte, including Hay Bay, Big Bay, and Muscote Bay.

Bay of Quinte Region
Quinte is also a region comprising several communities situated along the Bay of Quinte, including Quinte West, Brighton and the City of Belleville, which is the largest city in the Quinte Region, and represents a midpoint between Montreal, Ottawa, and Toronto.

The Greater Bay of Quinte area includes the municipalities of Brighton, Quinte West, Belleville, Prince Edward County, and Greater Napanee as well as the Native Tyendinaga Mohawk Territory. Overall population of the area exceeds 200,000.

Mohawks of the Bay of Quinte
The Mohawks of the Bay of Quinte (Kenhtè:ke Kanyen'kehá:ka) live on traditional Tyendinaga Mohawk Territory. Their reserve Band number 244, their current land base, is 73 km2 on the Bay of Quinte in southeastern Ontario east of Belleville and immediately to the west of Deseronto.

The community takes its name from a variant spelling of Mohawk leader Joseph Brant's traditional Mohawk name, Thayendanegea (standardized spelling Thayentiné:ken), which means 'two pieces of fire wood beside each other'. Officially, in the Mohawk language, the community is called "Kenhtè:ke" (Tyendinaga), which means "on the bay", and was the birthplace of Tekanawí:ta. The Cayuga name is Tyendinaga, Tayęda:ne:gęˀ or Detgayę:da:negęˀ, "land of two logs."

Communities

 * Belleville
 * Quinte West
 * Brighton
 * Shannonville
 * Napanee
 * Deseronto
 * Tyendinaga Mohawk Territory
 * Rossmore
 * Ameliasburgh
 * Picton
 * Consecon
 * Carrying Place

Education
The Quinte Region, specifically the City of Belleville, is home to Loyalist College of Applied Arts and Technology. Other post-secondary schools in the region include Maxwell College of Advanced Technology, CDI College, and Quinte Literacy. Secondary schools in the region include Albert College (private school) and Sir James Whitney (a school for the deaf and severely hearing-impaired).

Industry and employment
The Bay of Quinte region is a hub for industry in eastern Ontario. The region is home to a diverse cluster of domestic and multi-national manufacturing and logistics companies. Sectors include; food processing, auto-parts, plastics and packaging, consumer goods, and more. The region's close proximity to North American markets, strong labour force and start-up and operating costs have attracted attention and new investment from companies all over the globe. Industry in the Bay of Quinte region is supported by a workforce of over 11,000.

Investment attraction and industrial retention are supported regionally by the Quinte Economic Development Commission.

Just a few of over 350 industries located in the Bay of Quinte Region include:
 * Schütz Canada, German manufacturer of intermediate bulk containers
 * Essroc Canada a division of Italcementi
 * Magna Autosystems - lighting division (3 facilities)
 * Hannon Climate Control Canada Ltd.—Automotive parts
 * Procter and Gamble Inc.— Feminine hygiene products
 * Kellogg — Breakfast cereal manufacturer
 * Kruger - manufacturing facial and toilet tissue for the away from home market
 * Hain Celestial - manufacturing Yves Veggie Cuisine products
 * Sprague Foods - canned and jarred soups and beans
 * Donini Chocolate - a division of John Vince Foods
 * Redpath Sugar
 * Trenton Cold Storage Group Inc.—Refrigerated warehousing and distribution. Custom co-packing
 * Lactalis Canada—Black Diamond Cheese Division—Cheese manufacturing and packaging
 * Avaya—A telecommunications research and product development centre
 * Research Casting International—Canadian company specializing in moulding and casting for the production of museum exhibits
 * Cooney Transport Ltd.—Trucking company
 * Wellington Mushroom Farm / Highline Produce—Mushroom farm
 * Domtech—Copper wiring
 * ClearWater Design Canoe and Kayak—Boat manufacturer
 * The SAB Group of Companies Limited—Consumer goods company
 * Mapco Plastics—Biodegradable plastic packaging manufacturer
 * Citipack Distribution—Cash and carry
 * Babars Bazaar—International commodity trading
 * Jobsters Staffing—Staffing agency

title: Bay of Quinte