Lynx (constellation)

Lynx
Constellation

Abbreviation Lyn
Genitive Lyncis
Pronunciation /ˈlɪŋks/,
genitive /ˈlɪnsᵻs/
Symbolism the Lynx
Right ascension 8
Declination +45
Family Ursa Major
Quadrant NQ2
Area 545 sq. deg. (28th)
Main stars 4
Bayer/Flamsteed
stars		 42
Stars with planets 6
Stars brighter than 3.00m 0
Stars within 10.00 pc (32.62 ly) 1
Brightest star α Lyn (3.14m)
Nearest star LHS 1963
(28.1 ± 0.9 ly, 8.6 ± 0.3 pc)
Messier objects 0
Meteor showers Alpha Lyncids
September Lyncids
Bordering
constellations		 Ursa Major
Camelopardalis
Auriga
Gemini
Cancer
Leo (corner)
Leo Minor
Visible at latitudes between +90° and −55°.
Best visible at 21:00 (9 p.m.) during the month of March.

Lynx, named after the animal, is a constellation in the northern sky that was introduced in the 17th century by Johannes Hevelius. It is a faint constellation with its brightest stars forming a zigzag line. The orange giant Alpha Lyncis is the brightest star in the constellation, while the semiregular variable star Y Lyncis is a target for amateur astronomers. Six star systems have been found to contain planets. Those of 6 Lyncis and HD 75898 were discovered by the Doppler method; those of XO-2, XO-4, XO-5 and WASP-13 were observed as they passed in front of the host star.

Within the constellation's borders lie NGC 2419, an unusually remote globular cluster; the galaxy NGC 2770, which has hosted three recent Type Ib supernovae; the distant quasar APM 08279+5255, whose light is magnified and split into multiple images by the gravitational lensing effect of a foreground galaxy; and the Lynx Supercluster, which was the most distant supercluster known at the time of its discovery in 1999.

History

Depictions on star charts
An old drawing depicting a lynx overlaying a chart of stars
Earliest depiction of Lynx, in 1690
An old drawing depicting a lynx and telescope overlaying a chart of stars
Illustration from Urania's Mirror (1825). The obsolete constellation Telescopium Herschelii is to its right.

Polish astronomer Johannes Hevelius formed the constellation in the 17th century from 19 faint stars that he observed with the unaided eye between the constellations Ursa Major and Auriga. Naming it Lynx because of its faintness, he challenged future stargazers to see it, declaring that only the lynx-eyed (those with good sight) would have been able to recognize it. Hevelius gave it the alternate name of Tiger in his catalogue as well, but kept the former name only in his atlas. English astronomer John Flamsteed adopted the constellation in his catalogue, published in 1712, and his subsequent atlas.[1] According to 19th-century amateur astronomer Richard Hinckley Allen, the chief stars in Lynx "might well have been utilized by the modern constructor, whoever he was, of our Ursa Major to complete the quartette of feet."[2]

Characteristics

Lynx is bordered by Camelopardalis to the north, Auriga to the west, Gemini to the southwest, Cancer to the south, Leo to the east and Ursa Major to the northeast. Covering 545.4 square degrees and 1.322% of the night sky, it ranks 28th of the 88 constellations in size,[3] surpassing better known constellations such as Gemini.[4] The three-letter abbreviation for the constellation, as adopted by the International Astronomical Union in 1922, is 'Lyn'.[5] The official constellation boundaries, as set by Eugène Delporte in 1930,[lower-alpha 1] are defined by a polygon of 20 segments (illustrated in infobox). In the equatorial coordinate system, the right ascension coordinates of these borders lie between 06h 16m 13.76s and 09h 42m 50.22s, while the declination coordinates are between +32.97° and +61.96°.[7] On dark nights, the brighter stars can be seen as a crooked line extending roughly between Camelopardalis and Leo,[8] and north of the bright star Castor.[2] Lynx is most readily observed from the late winter to late summer to northern hemisphere observers, with midnight culmination occurring on 20 January.[8] The whole constellation is visible to observers north of latitude 28°S.[lower-alpha 2]

Notable features

Stars

English astronomer Francis Baily gave a single star a Bayer designation—Alpha Lyncis—while Flamsteed numbered 44 stars, though several lie across the boundary in Ursa Major.[9] Overall, there are 97 stars within the constellation's borders brighter than or equal to apparent magnitude 6.5.[lower-alpha 3][3]

The brightest star in this constellation is Alpha Lyncis, with an apparent (visual) magnitude of 3.14.[11] It is an orange giant of spectral type K7III located 203 ± 2 light-years distant from Earth.[12] Around twice as massive as the Sun,[13] it has exhausted the hydrogen at its core and has evolved away from the main sequence. The star has swollen to about 55 times the Sun's radius and it is emitting roughly 673 times the luminosity of the Sun. The stellar atmosphere has cooled, giving it a surface temperature of 3,880 K.[14] The only star with a proper name is Alsciaukat (from the Arabic for thorn), also known as 31 Lyncis, located 380 ± 10 light-years from Earth.[12] This star is also an evolved giant with around twice the Sun's mass that has swollen and cooled since exhausting its core hydrogen. It is anywhere from 59 to 75 times as wide as the Sun, and 740 times as luminous.[13] Alsciaukat is also a variable star, ranging in brightness by 0.05 magnitude over 25 to 30 days from its baseline magnitude of 4.25.[15]

Lynx is rich in double stars.[2] The second brightest star in the constellation is 38 Lyncis at magnitude 3.8. When viewed through a moderate telescope, the two components—a brighter blue-white star of magnitude 3.9 and a fainter star of magnitude 6.1 that has been described as lilac as well as blue-white—can be seen.[16] 15 Lyncis is another star that is found to be a double system when viewed through a telescope, separating into two yellowish stars of magnitudes 4.7 and 5.8 that are 0.9 arcseconds apart.[16] The components are a yellow giant of spectral type G8III that is around 4.01 times as massive as the Sun, and a yellow-white main sequence star of spectral type F8V that is around 3.73 times as massive as the Sun. Orbiting each other every 262 years,[17] the stars are 178 ± 2 light years distant from Earth.[12] 12 Lyncis has a combined apparent magnitude of 4.87. When seen through a telescope, it can be separated into three stars: two components with magnitudes 5.4 and 6.0 that lie at an angular separation by 1.8″ (as of 1992) and a yellow-hued star of magnitude 7.2 at a separation of 8.6″ (as of 1990).[16][18] The two brighter stars are estimated to orbit each other with a period that is poorly known but estimated to be roughly 700 to 900 years.[17] The 12 Lyncis system is 210 ± 10 light years distant from Earth.[12]

10 Ursae Majoris is the third-brightest star in Lynx. Originally in the neighbouring constellation Ursa Major, it became part of Lynx with the official establishment of the constellation's borders.[19] Appearing to be of magnitude 3.97, a telescope reveals a yellow-white main sequence star of spectral type F4V of magnitude 4.11 and a star very similar to the Sun of spectral type G5V and magnitude 6.18. The two are 10.6 astronomical units (au)[lower-alpha 4] apart and orbit each other every 21.78 years.[20] The system is 52.4 ± 0.6 light-years distant from Earth.[12] Likewise 16 Lyncis was originally known as Psi10 Aurigae and conversely, 37, 39, 41 and 44 Lyncis became part of Ursa Major.[9]

Y Lyncis is a popular target among amateur astronomers, as it is a semiregular variable ranging in brightness from magnitude 6.2 to 8.9.[21] These shifts in brightness are complex, with a shorter period of 110 days due to the star's pulsations, and a longer period of 1400 days possibly due to the star's rotation or regular cycles in its convection.[22] A red supergiant, it has an estimated diameter around 580 times that of the Sun, is around 1.5 to 2 times as massive, and has a luminosity around 25,000 times that of the Sun.[21] 1 Lyncis and UX Lyncis are red giants that are also semiregular variables with complex fluctuations in brightness.[22]

Six star systems have been found to contain exoplanets, of which two were discovered by the Doppler method and four by the transit method. 6 Lyncis, an orange subgiant that spent much of its life as an A-type or F-type main sequence star, is orbited by a planet with a minimum mass of 2.4 Jupiter masses and an orbital period of 899 days.[23] HD 75898 is a 3.8 ± 0.8 billion-year-old yellow star of spectral type G0V that has just begun expanding and cooling off the main sequence. It has a planet at least 2.51 times as massive as Jupiter orbiting with a period of around 418 days. The centre of mass of the system is accelerating, indicating there is a third, more distant, component at least the size of Jupiter.[24] Three star systems were found to have planets that were observed by the XO Telescope in Hawaii as they passed in front of them. XO-2 is a binary star system, both the stars of which are slightly less massive and cooler than the Sun and have planetary companions: XO-2S has a Saturn-mass planet at 0.13 au distance with a period of around 18 days, and one a little more massive than Jupiter at a distance of 0.48 au and with a period of around 120 days,[25] while XO-2N has a hot jupiter with around half Jupiter's mass that has an orbit of only 2.6 days.[26] XO-4 is an F-type main sequence star that is a little hotter and more massive than the Sun that has a hot jupiter orbiting with a period of around 4.1 days.[27] XO-5 is a Sun-like star with a hot jupiter about as massive as Jupiter that takes around 4.2 days to complete an orbit.[28] WASP-13, a sun-like star that has begun to swell and cool off the main sequence, had a transiting planet discovered by the SuperWASP program in 2009. The planet is around half as massive as Jupiter and takes 4.35 days to complete a revolution.[29]

Deep-sky objects

a round cluster of tiny distant stars with two bright bluish stars to the upper left
NGC 2419 (Credit: Adam Block/Mount Lemmon SkyCenter/University of Arizona)

Lynx's most notable deep sky object is NGC 2419, also called the "Intergalactic Wanderer" as it was assumed to lie outside the Milky Way. At a distance of between 275,000 and 300,000 light-years from Earth, it is one of the most distant known globular clusters within our galaxy. NGC 2419 is likely in a highly elliptical orbit around the Milky Way.[30] It has a magnitude of 10.3 and is a Shapley class II cluster; this classification indicates that it is extremely concentrated at its center. Originally thought to be a star, NGC 2419 was discovered to be a globular cluster by American astronomer Carl Lampland.[31]

NGC 2537, known as the Bear's Paw Galaxy, lies about 3 degrees north-northwest of 31 Lyncis.[32] It is a blue compact dwarf galaxy that is somewhere between 17 and 30 million light-years away from Earth. Close by is IC 2233, a very flat and thin spiral galaxy that is between 26 and 40 million light-years away from Earth. A comparatively quiet galaxy with a low rate of star formation (less than one solar mass every twenty years), it was long suspected to be interacting with the Bear's Paw galaxy. This is now considered highly unlikely as observations with the Very Large Array showed the two galaxies lie at different distances.[33]

The NGC 2841 group is a group of galaxies that lie both in Lynx and neighbouring Ursa Major. It includes the loose triplet NGC 2541, NGC 2500, and NGC 2552 within Lynx. Using cepheids of NGC 2541 as standard candles, the distance to that galaxy (and the group) has been estimated at around 40 million light–years.[34] NGC 2841 itself lies in Ursa Major.[35]

NGC 2770 is a type SASc spiral galaxy located about 88 million light–years away that has hosted Type Ib supernovae: SN 1999eh, SN 2007uy, and SN 2008D.[36] The last of these is famous for being the first supernova detected by the X-Rays released very early on in its formation, rather than by the optical light emitted during later stages, which allowed the first moments of the outburst to be observed. It is possible that NGC 2770's interactions with a suspected companion galaxy may have created the massive stars causing this activity.[37] UGC 4904 is a galaxy located about 77 million light-years from Earth. On 20 October 2004, a supernova impostor was observed by Japanese amateur astronomer Koichi Itagaki within the galaxy. Observations of its spectrum suggest that it shed massive amounts of material in a two-year period, transforming from a LBV star to a Wolf–Rayet star,[38][39] before it was observed erupting as hypernova SN 2006jc on October 11, 2006.[40]

APM 08279+5255 is a very distant, broad absorption line quasar discovered in 1998 and initially considered the most luminous object yet found. It is magnified and split into multiple images by the gravitational lensing effect of a foreground galaxy through which its light passes.[41] It appears to be a giant elliptical galaxy with a supermassive black hole around 23 billion times as massive as the Sun and an associated accretion disk that has a diameter of 3600 light years. The galaxy possesses large regions of hot dust and molecular gas, as well as regions with starburst activity. It has a cosmological redshift of 3.911.[42][lower-alpha 5] While observing the quasar in 2008, astronomers using ESA's XMM Newton and the Large Binocular Telescope (LBT) in Arizona discovered the huge galaxy cluster 2XMM J083026+524133.[43][44]

The Lynx Supercluster is a remote supercluster with a redshift of 1.26–1.27.[45] It was the most distant supercluster known at the time of its discovery in 1999.[46] It is made up of two main clusters of galaxies—RX J0849+4452 or Lynx E and RX J0848+4453 or Lynx W—and several smaller clumps.[45] Further still lies the Lynx Arc, located around 12 billion light years away (a redshift of 3.357). It is a distant region containing a million extremely hot, young blue stars with surface temperatures of 80,000–100,000 K that are twice as hot as similar stars in the Milky Way galaxy. Only visible through gravitational lensing produced by a closer cluster of galaxies, the Arc is a feature of the early days of the universe, when "furious firestorms of star birth" were more common.[47]

Meteor showers

The September Lyncids are a minor meteor shower that appears around 6 September. They were historically more prominent, described as such by Chinese observers in 1037 and 1063, and Korean astronomers in 1560.[48] The Alpha Lyncids were discovered in 1971 by Malcolm Currie,[49] and appear between 10 December and 3 January.[50]

See also

Notes

  1. ↑ Delporte had proposed standardising the constellation boundaries to the International Astronomical Union, who had agreed and gave him the lead role[6]
  2. ↑ While parts of the constellation technically rise above the horizon to observers between 28°S and 57°S, stars within a few degrees of the horizon are to all intents and purposes unobservable.[3]
  3. ↑ Objects of magnitude 6.5 are among the faintest visible to the unaided eye in suburban-rural transition night skies.[10]
  4. ↑ the distance between the Earth and the Sun is one astronomical unit
  5. ↑ Far distant objects are measured in redshift rather than light-years. See also Hubble's law

References

  1. ↑ Wagman 2003, pp. 202–03.
  2. 1 2 3 Allen, Richard Hinckley (1963) [1899]. Star Names: Their Lore and Meaning (reprint ed.). New York, New York: Dover Publications. p. 280. ISBN 978-0-486-21079-7.
  3. 1 2 3 Ridpath, Ian. "Constellations: Lacerta–Vulpecula". Star Tales. Self-published. Retrieved 7 March 2016.
  4. ↑ Ridpath, Ian. "Lynx". Star Tales. Self-published. Retrieved 8 March 2016.
  5. ↑ Russell, Henry Norris (1922). "The New International Symbols for the Constellations". Popular Astronomy. 30: 469. Bibcode:1922PA.....30..469R.
  6. ↑ Ridpath, Ian. "Constellation boundaries: How the modern constellation outlines came to be". Star Tales. self-published. Retrieved 1 June 2016.
  7. ↑ "Lynx, Constellation Boundary". The Constellations. International Astronomical Union. Retrieved 7 March 2016.
  8. 1 2 Thompson, Robert Bruce; Barbara Fritchman. Illustrated Guide to Astronomical Wonders: From Novice to Master Observer. Sebastopol, California: O'Reilly Media, Inc. pp. 302–07. ISBN 978-0-596-52685-6.
  9. 1 2 Wagman 2003, pp. 433–34.
  10. ↑ Bortle, John E. (February 2001). "The Bortle Dark-Sky Scale". Sky & Telescope. Sky Publishing Corporation. Retrieved 4 March 2016.
  11. ↑ Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues. 2237. Bibcode:2002yCat.2237....0D.
  12. 1 2 3 4 5 van Leeuwen, F. (2007). "Validation of the New Hipparcos Reduction". Astronomy and Astrophysics. 474 (2): 653–64. arXiv:0708.1752Freely accessible. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357.
  13. 1 2 Kaler, James B. (11 May 2005). "Alpha Lyn (Alpha Lyncis) and Alsciaukat (31 Lyncis)". Stars. University of Illinois. Retrieved 9 March 2016.
  14. ↑ Piau, L.; Kervella, P.; Dib, S.; Hauschildt, P. (2010). "Surface convection and red giants radii measurements". Astronomy and Astrophysics. 526: 100. arXiv:1010.3649Freely accessible. Bibcode:2011A&A...526A.100P. doi:10.1051/0004-6361/201014442. For Mbol, see Table 1.
  15. ↑ Percy, John R. (1993). "The photometric variability of K giants". Publications of the Astronomical Society of the Pacific. 105 (694): 1422–26. Bibcode:1993PASP..105.1422P. doi:10.1086/133324.
  16. 1 2 3 Monks, Neale (2010). Go-To Telescopes Under Suburban Skies. New York, New York: Springer Science & Business Media. pp. 56–58. ISBN 978-1-4419-6851-7.
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  18. ↑ Mason, Brian D.; Wycoff, Gary L.; Hartkopf, William I.; Douglass, Geoffrey G.; Worley, Charles E. (2001). "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog". The Astronomical Journal. 122 (6): 3466. Bibcode:2001AJ....122.3466M. doi:10.1086/323920.
  19. ↑ Bagnall, Philip M. (2012). The Star Atlas Companion: What You Need to Know about the Constellations. New York, New York: Springer. p. 281. ISBN 1-4614-0830-X.
  20. ↑ Kaler, James B. "10 UMA (10 Ursae Majoris) = HR 3579 Lyncis". Stars. University of Illinois. Retrieved 9 March 2016.
  21. 1 2 Szatmary, Karoly; Vinko, Jozsef (1992). "Periodicities of the light curve of the semiregular variable star Y Lyncis". Monthly Notices of the Royal Astronomical Society. 256 (2): 321–28. Bibcode:1992MNRAS.256..321S. doi:10.1093/mnras/256.2.321.
  22. 1 2 Percy, John R.; Wilson, Joseph B.; Henry, Gregory W. (2001). "Long-Term VRI Photometry of Small-Amplitude Red Variables. I. Light Curves and Periods". The Publications of the Astronomical Society of the Pacific. 113 (786): 983–96. Bibcode:2001PASP..113..983P. doi:10.1086/322153.
  23. ↑ Sato, Bun'ei; Toyota, Eri; Omiya, Masashi; Izumiura, Hideyuki; Kambe, Eiji; Masuda, Seiji; Takeda, Yoichi; Itoh, Yoichi; Ando, Hiroyasu (2008). "Planetary Companions to Evolved Intermediate-Mass Stars: 14 Andromedae, 81 Ceti, 6 Lyncis, and HD167042". Publications of the Astronomical Society of Japan. 60 (6): 1317–1326. arXiv:0807.0268Freely accessible. Bibcode:2008PASJ...60.1317S. doi:10.1093/pasj/60.6.1317.
  24. ↑ Robinson, Sarah E.; Laughlin, Gregory; Vogt, Steven S.; Fischer, Debra A.; Butler, R. Paul; Marcy, Geoffrey W.; Henry, Gregory W.; Driscoll, Peter; Takeda, Genya; Johnson, John A. (2007). "Two Jovian-Mass Planets in Earthlike Orbits". The Astrophysical Journal. 670 (2): 1391–1400. arXiv:0708.0832Freely accessible. Bibcode:2007ApJ...670.1391R. doi:10.1086/522106.
  25. ↑ Desidera, S.; Bonomo, A. S.; Claudi, R.U.; Damasso, M.; Biazzo, K.; Sozzetti, A.; Marzari, F.; Benatti, S.; Gandolfi, D.; Gratton, R.; Lanza, A.F.; Nascimbeni, V.; Andreuzzi, G.; Affer, L.; Barbieri, M.; Bedin, L. R.; Bignamini, A.; Bonavita, M.; Borsa, F.; Calcidese, P.; Christille, J. M.; Cosentino, R.; Covino, E.; Esposito, M.; Giacobbe, P.; Harutyunyan, A.; Latham, D.; Lattanzi, M.; Leto, G.; Lodato, G.; Lovis, C.; Maggio, A.; Malavolta, L.; Mancini, L.; Martinez Fiorenzano, A.F.; Micela, G.; Molinari, E.; Mordasini, C.; Munari, U.; Pagano, I.; Pedani, M.; Pepe, F.; Piotto, G.; Poretti, E.; Rainer, M.; Ribas, I.; Santos, N. C.; Scandariato, G.; Silvotti, R.; Southworth, J.; Zanmar Sanchez, R. (2014). "The GAPS programme with HARPS-N at TNG IV: A planetary system around XO-2S". Astronomy & Astrophysics. 567 (6): L6. arXiv:1407.0251Freely accessible. Bibcode:2014A&A...567L...6D. doi:10.1051/0004-6361/201424339.
  26. ↑ Burke, Christopher J.; McCullough, P. R.; Valenti, Jeff A.; Johns‐Krull, Christopher M.; Janes, Kenneth A.; Heasley, J. N.; Summers, F. J.; Stys, J. E.; Bissinger, R.; Fleenor, Michael L.; Foote, Cindy N.; Garcia‐Melendo, Enrique; Gary, Bruce L.; Howell, P. J.; Mallia, F.; Masi, G.; Taylor, B.; Vanmunster, T. (2007). "XO-2b: Transiting Hot Jupiter in a Metal-rich Common Proper Motion Binary". The Astrophysical Journal. 671 (2): 2115–28. arXiv:0705.0003Freely accessible. Bibcode:2007ApJ...671.2115B. doi:10.1086/523087.
  27. ↑ McCullough, P. R.; Burke, Christopher J.; Valenti, Jeff A.; Long, Doug; Johns‐Krull, Christopher M.; Machalek, P.; Janes, K. A.; Taylor, B.; Gregorio, J. (2008). "XO-4b: An Extrasolar Planet Transiting an F5V Star". arXiv:0805.2921Freely accessible. Bibcode:2008arXiv0805.2921M.
  28. ↑ Burke, Christopher J.; McCullough, P. R.; Valenti, Jeff A.; Long, Doug; Johns‐Krull, Christopher M.; Machalek, P.; Janes, Kenneth A.; Taylor, B.; Fleenor, Michael L. (2008). "XO-5b: A Transiting Jupiter-sized Planet with a 4 day Period". The Astrophysical Journal. 686 (2): 1331–40. arXiv:0805.2399Freely accessible. Bibcode:2008ApJ...686.1331B. doi:10.1086/591497.
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  30. ↑ Harrington, Philip S. (2010). Cosmic Challenge: The Ultimate Observing List for Amateurs. Cambridge, United Kingdom: Cambridge University Press. p. 189. ISBN 978-1-139-49368-0.
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  32. ↑ Plotner, Tammy (2007). The Night Sky Companion: A Yearly Guide to Sky-Watching 2008–2009. New York, New York: Springer Science. p. 65. ISBN 978-0-387-71609-1.
  33. ↑ Matthews, Lynn D.; Uson, Juan M. (2007). "H I Imaging Observations of Superthin Galaxies. II. IC 2233 and the Blue Compact Dwarf NGC 2537". The Astronomical Journal. 135 (1): 291. Bibcode:2008AJ....135..291M. doi:10.1088/0004-6256/135/1/291.
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  35. ↑ Crossen, Craig; Rhemann, Gerald (2012). Sky Vistas: Astronomy for Binoculars and Richest-Field Telescopes. New York, New York: Springer. p. 230. ISBN 978-3-7091-0626-6.
  36. ↑ Thoene, Christina C.; Michałowski, Michał J.; Leloudas, Giorgos; Cox, Nick L.J.; Fynbo, Johan P.U.; Sollerman, Jesper; Hjorth, Jens; Vreeswijk, Paul M. (2009). "NGC 2770 – a supernova Ib factory?". The Astrophysical Journal. 698 (2): 1307. arXiv:0807.0473v1Freely accessible. doi:10.1088/0004-637X/698/2/1307.
  37. ↑ "Catching the Light of a Baby Supernova". Gemini Observatory. Archived from the original on 7 July 2015. Retrieved 7 July 2015.
  38. ↑ Foley, Ryan J.; Smith, Nathan; Ganeshalingam, Mohan; Li, Weidong; Chornock, Ryan; Filippenko, Alexei V. (2007). "SN 2006jc: A Wolf-Rayet star exploding in a dense He-rich circumstellar medium.". The Astrophysical Journal Letters. 657 (2): L105.
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  42. ↑ Riechers, Dominik A.; Walter, Fabian; Carilli, Christopher L.; Lewis, Geraint F. (2009). "Imaging The Molecular Gas in a z = 3.9 Quasar Host Galaxy at 0."3 Resolution: A Central, Sub-Kiloparsec Scale Star Formation Reservoir in APM 08279+5255". The Astrophysical Journal. 690 (1): 463–85. arXiv:0809.0754Freely accessible. Bibcode:2009ApJ...690..463R. doi:10.1088/0004-637X/690/1/463.
  43. ↑ Baldwin, Emily (27 August 2008). "XMM discovers monster galaxy cluster". Astronomy Now. Retrieved 4 July 2016.
  44. ↑ Lamer, G.; Hoeft, M.; Kohnert, J.; Schwope, A.; Storm, J. (2008). "2XMM J083026+524133: the most X-ray luminous cluster at redshift 1". Astronomy and Astrophysics. 487 (2): L33–L36. arXiv:0805.3817Freely accessible. Bibcode:2008A&A...487L..33L. doi:10.1051/0004-6361:200810255.
  45. 1 2 Mei, Simona; Stanford, S. Adam; Holden, Brad P.; Raichoor, Anand; Postman, Marc; Nakata, Fumiaki; Finoguenov, Alexis; Ford, Holland C.; Illingworth, Garth D.; Kodama, Tadayuki; Rosati, Piero; Tanaka, Masayuki; Huertas-Company, Marc; Rettura, Alessandro; Shankar, Francesco; Carrasco, Eleazar R.; Demarco, Ricardo; Eisenhardt, Peter; Jee, Myungkook J.; Koyama, Yusei; White, Richard L. (2012). "Early-type Galaxies at z = 1.3. I. The Lynx Supercluster: Cluster and Groups at z = 1.3. Morphology and Color-Magnitude Relation". The Astrophysical Journal. 754 (2): 20. arXiv:1205.1785Freely accessible. Bibcode:2012ApJ...754..141M. doi:10.1088/0004-637X/754/2/141. 141.
  46. ↑ Nakata, F. (2004). Discovery of a large-scale clumpy structure of the Lynx supercluster at z~1.27. Proceedings of the International Astronomical Union. 2004. Cambridge University Press. pp. 29–33. Bibcode:2004ogci.conf...29N. doi:10.1017/S1743921304000080. ISBN 0-521-84908-X.
  47. ↑ Fosbury, R.A.E.; Villar-Martín, M.; Humphrey, A.; Lombardi, M.; Rosati, P.; Stern, D.; Hook, R.N.; Holden, B.P.; Stanford, S.A.; Squires, G.K.; Rauch, M.; Sargent, W.L.W. (2003). "Massive Star Formation in a Gravitationally Lensed H II Galaxy at z = 3.357". The Astrophysical Journal. 596 (2): 797–809. arXiv:astro-ph/0307162Freely accessible. Bibcode:2003ApJ...596..797F. doi:10.1086/378228.
  48. ↑ Sherrod, P. Clay; Koed, Thomas L. (2003). A Complete Manual of Amateur Astronomy: Tools and Techniques for Astronomical Observations. New York, New York: Dover Publications. p. 56. ISBN 978-0-486-42820-8.
  49. ↑ Jenniskens 2006, p. 198.
  50. ↑ Jenniskens 2006, p. 738.

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