Aquila (constellation)
Constellation | |
Altair (α Aql) (0.76m) | |
Messier objects | 0 |
---|---|
Meteor showers | |
Bordering constellations | |
Visible at latitudes between + 90° and −75 °.Best visible at 21:00 (9 p.m.) during the month of August. |
Aquila is a
Its brightest star, Altair, is one vertex of the Summer Triangle asterism. The constellation is best seen in the northern summer, as it is located along the Milky Way. Because of this location, many clusters and nebulae are found within its borders, but they are dim and galaxies are few.
History
Aquila was one of the 48 constellations described by the second-century astronomer Ptolemy. It had been earlier mentioned by Eudoxus in the fourth century BC and Aratus in the third century BC.[3]
It is now one of the 88 constellations defined by the International Astronomical Union. The constellation was also known as Vultur volans (the flying vulture) to the Romans, not to be confused with Vultur cadens which was their name for Lyra. It is often held to represent the eagle which held Zeus's/Jupiter's thunderbolts in Greco-Roman mythology. Aquila is also associated with the eagle that kidnapped Ganymede, a son of one of the kings of Troy (associated with Aquarius), to Mount Olympus to serve as cup-bearer to the gods.[1]
Ptolemy catalogued 19 stars jointly in this constellation and in the now obsolete constellation of Antinous, which was named in the reign of the emperor Hadrian (AD 117–138), but sometimes erroneously attributed to Tycho Brahe, who catalogued 12 stars in Aquila and seven in Antinous. Hevelius determined 23 stars in the first[4] and 19 in the second.[4][3]
The Greek Aquila is probably based on the Babylonian constellation of the Eagle, but is sometimes mistakenly thought as a seagull which is located in the same area as the Greek constellation.[5]
Notable features
Stars
Aquila, which lies in the Milky Way, contains many rich starfields and has been the location of many novae.[1]
- γ Aql (Tarazed) is an orange-hued giant star of around magnitude 2.7,[15] 460 light-years from Earth. Its name, like that of Alshain, comes from the Arabic for "the balance".[1] It is the second-brightest star in the constellation and is an unconfirmed variable star.[16]
- F-type main sequence star.[22]
- A-type star with a lower metallicity than the Sun.[25]
- 57 Aql is a binary star. The primary is a blue-hued star of magnitude 5.7 and the secondary is a white star of magnitude 6.5. The system is approximately 350 light-years from Earth; the pair is easily resolved in small amateur telescopes.[1] Both stars in the system rotate rapidly.[28]
- R Aql is a red-hued giant star 690 light-years from Earth. It is a Mira variable with a minimum magnitude of 12.0, a maximum magnitude of 6.0, and a period around 9 months. It has a diameter of 400 D☉.[1]
- V Aql is a typical Cool Carbon Star. It's one of the most red-colored examples of this sort of stars, observable through common amateur telescopes.
- FF Aql is a yellow-white-hued supergiant star, 2500 light-years from Earth. It is a Cepheid variable star with a minimum magnitude of 5.7, a maximum magnitude of 5.2, and a period of 4.5 days.[1] It is a spectroscopic binary with a spectral type of F6Ib.[29] A third star is also a member of the system,[30] and there is also a fourth star which is probably unconnected with the main system.[31][32]
Novae
A bright nova was observed in Aquila in 1918 (
Deep-sky objects
Three interesting planetary nebulae lie in Aquila:
- NGC 6804 shows a small but bright ring.
- NGC 6781 bears some resemblance with the Owl Nebula in Ursa Major. It was discovered by William Herschel in 1788.[36]
- Glowing Eye, is a planetary nebula. The nebula is estimated to be roughly 0.8 light-years in diameter.[37]
More deep-sky objects:
- NGC 6709 is a loose open cluster containing roughly 40 stars, which range in magnitude from 9 to 11. It is about 3000 light-years from Earth.[1] It has an overall magnitude of 6.7 and is about 9100 light-years from Earth. NGC 6709 appears in a rich Milky Way star field and is classified as a Shapley class d and Trumpler class III 2 m cluster. These designations mean that it does not have many stars, is loose, does not show greater concentration at the center, and has a moderate range of star magnitudes.[38] There are 305 confirmed member stars[39] and one candidate red giant.[40]
- NGC 6755 is an open cluster of 7.5 m; it is made up of about a dozen stars with magnitudes 12 through 13. It is located approximately 8,060 light-years from the Solar System.[41]
- Shapley-Sawyer Concentration Class of IX.[43]
- NGC 6749 is an open cluster.
- NGC 6778 is a planetary nebula located about 10,300 light-years away from the Solar System.[44]
- NGC 6741 is a planetary nebula.
- NGC 6772 is a planetary nebula.
- W51 (3C400) is one of the largest stellar nurseries in the Milky Way. Located about 17,000 light-years from Earth, W51 is about 350 light-years – or about 2 quadrillion miles – across. However, it's located in an area so thick with interstellar dust that it's opaque to visible light. Observations by the Chandra X-Ray Observatory and the Spitzer Infrared Telescope reveal W51 would appear about as large as the full Moon in visible light.[45][46]
Aquila also holds some extragalactic objects. One of them is what may be the largest single mass concentration of galaxies in the Universe known, the Hercules–Corona Borealis Great Wall. It was discovered in November 2013, and has the size of 10 billion light years. It is the biggest and the most massive structure in the Universe known.
Other
NASA's Pioneer 11 space probe, which flew by Jupiter and Saturn in the 1970s, is expected to pass near the star Lambda (λ) Aquilae in about 4 million years.[47]
Illustrations
In illustrations of Aquila that represent it as an eagle, a nearly straight line of three stars symbolizes part of the wings. The center and brightest of these three stars is Altair.[citation needed]
Mythology
This section needs additional citations for verification. (November 2009) |
According to Gavin White, the Babylonian Eagle carried the constellation called the Dead Man in its talons. The author also draws a comparison to the classical stories of Antinous and Ganymede.[5]
In classical Greek mythology, Aquila was identified as Αετός Δίας (
In the Chinese love story of
In Hinduism, the constellation Aquila is identified with the half-eagle half-human deity Garuda.[50][51]
In ancient Egypt, Aquila possibly was seen as the falcon of Horus.[52] According to Berio, the identification of Aquila as an Egyptian constellation, and not merely Graeco-Babylonian, is corroborated by the Daressy Zodiac.[53] It depicts an outer ring showing the Sphaera Graeca, the familiar Hellenistic zodiac, while the middle ring depicts the Sphaera Barbarica or foreigner's zodiac with the zodiacal signs of the Egyptian dodekaoros which were also recorded by Teucros of Babylon.[54] Under the sign of Sagittarius is the falcon of Horus, presumably because Aquila rises with Sagittarius.
Equivalents
In
Several different
See also
- Aquila (Chinese astronomy)
References
- Citations
- ^ a b c d e f g h i j k l m n o p Ridpath 2001, pp. 80–82
- ^ a b "Aquila, constellation boundary". The Constellations. International Astronomical Union. Retrieved 14 February 2014.
- ^ a b Chisholm 1911.
- ^ a b "Prodromus astronomiae". 1690. pp. 272–273. Archived from the original on 2011-07-27.
- ^ a b White 2008, p. 95
- ^ NAME ALTAIR -- Variable Star of delta Sct type, database entry, SIMBAD. Accessed on line November 25, 2008.
- ^ Altair, entry, The Internet Encyclopedia of Science, David Darling. Accessed on line November 25, 2008.
- ^ Summer Triangle, entry, The Internet Encyclopedia of Science, David Darling. Accessed on line November 26, 2008.
- ^ S2CID 4615273. See second column of Table 1 for stellar parameters.)
{{cite journal}}
: CS1 maint: postscript (link - ^ S2CID 18683397. See Table 2 for stellar parameters.
- S2CID 13969695.
- S2CID 119476992.
- .
- S2CID 214802418
- Bibcode:1984SAAOC...8...59C
- Bibcode:1991TrSht..63....1K.
- ^ "Naming Stars". IAU.org. Retrieved 30 July 2018.
- ^ .
- doi:10.1086/110819
- S2CID 186212958.
- S2CID 34133110.
- S2CID 55702630.
- ISBN 978-1-4471-3613-2.
- Bibcode:1992JRASC..86..221L
- S2CID 131780028.
- S2CID 118361131.
- Bibcode:1964MNSSA..23..175C.
- doi:10.1086/340590.
- S2CID 122811461.
- ISSN 0004-6256.
- S2CID 55702630.
- ISSN 0004-6256.
- ^ The Contribution of Amateurs to Astronomy, Proceedings of Colloquium 98 of the International Astronomical Union, June 20–24, 1987, page 41
- ISBN 978-0-387-79946-9.
- S2CID 118403602.
- ^ Seligman, Courtney. "NGC Objects: NGC 6750 - 6799". Celestial Atlas. Retrieved 2021-01-07.
- ^ "The Glowing Eye of Planetary Nebula NGC 6751". HubbleSite. 2000-04-06. Retrieved 2021-04-12.
- ^ Levy 2005, pp. 79–80.
- . 175.
- S2CID 34294008.
- S2CID 208138247. A99.
- S2CID 119342837.
- Bibcode:1927BHarO.849...11S.
- .
- ^ "Spitzer Image of Star Factory W51". Jet Propulsion Laboratory.
- ^ "Chandra :: Photo Album :: W51 :: July 12, 2017".
- ^ "Hardware, Leaving the Solar System:Where are they now?", DK Eyewitness Space Encyclopedia
- ^ "Urania's Mirror c.1825 – Ian Ridpath's Antique Star Atlases". Ianridpath.com. Retrieved 2012-10-21.
- ^ "Star Tales – Lyra". Ianridpath.com. Retrieved 2021-07-05.
- ^ Raymond L. Langsten; Marc Jason Gilbert (1983), Research on Bengal: proceedings of the 1981 Bengal Studies Conference, Issue 34 of South Asia series, Michigan State University Asian Studies Center, Asian Studies Center, Michigan State University, 1983,
... and the appearance of the constellation Aquila that marks ... As Aquila was an eagle for the Greeks, it is the Garuda kite to Hindus...
- ISBN 978-81-223-0366-7,
... later spread to other cultures such as Arab, Hindu, Greek and Roman where the names were reinterpreted to suit the local cultures. Hence Aquila/Garuda, Leo/Singha, Hydra/Vasuki and other similarities in names ...
- Bibcode:2014SPP...253....1B.
- ^ Daressy, Georges (1916). "L'Égypte céleste". Bulletin de l'Institut Français d'Archéologie Orientale. 12: 1–37.
- ^ "Boll, Franz: Sphaera: neue griechische Texte und Untersuchungen zur Geschichte der Sternbilder (Leipzig, 1903)". digi.ub.uni-heidelberg.de. Retrieved 2016-10-21.
- ^ Makemson 1941, p. 218.
- ^ Nā Puke Wehewehe ʻŌlelo Hawaiʻi
- ^ Makemson 1941, p. 212.
- ^ Makemson 1941, p. 240.
- ^ Makemson 1941, p. 262.
- ^ Makemson 1941, p. 263.
- ^ Makemson 1941, p. 256.
- ^ Makemson 1941, p. 264.
- ^ Makemson 1941, p. 245.
- References
- public domain: Chisholm, Hugh, ed. (1911). "Aquila". Encyclopædia Britannica. Vol. 2 (11th ed.). Cambridge University Press. p. 249. This article incorporates text from a publication now in the
- Levy, David H. (2005), Deep Sky Objects, Prometheus Books, ISBN 1-59102-361-0
- Makemson, Maud Worcester (1941). The Morning Star Rises: an account of Polynesian astronomy. Bibcode:1941msra.book.....M.
- Ridpath, Ian (2001), Stars and Planets, Illustrated by Wil Tirion (3rd ed.), Princeton University Press, ISBN 0-691-08913-2
- Ridpath, Ian (2007), Stars and Planets Guide, Wil Tirion (4th ed.), Princeton University Press, ISBN 978-0-691-13556-4
- White, Gavin (2008), Babylonian Star-lore, Solaria Pubs