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Aquila supplies the low, southern corner of the Summer Triangle; for the full picture of the Triangle — Vega, Deneb, and Altair together — and how to use it to orient yourself, see Cygnus. On its own, look for the tight Tarazed–Altair–Alshain line: nothing else nearby has that same bracketed, weighing-scale look. Aquila straddles the celestial equator (its stars run from about Dec +14° to Dec -5°), so from Ohio it behaves roughly like the Sun near the equinoxes — up for something close to half of each 24-hour period, well clear of the horizon by full dark from June through September, and not circumpolar. Best viewed full dark, roughly 9:30–11:30 p.m., in August.

Star	RA (h)	Dec (°)	Mag	Name
Altair	19.846	+8.87	0.76	Arabic al-nasr al-tā'ir, "the flying eagle"
Tarazed (Gamma Aql)	19.771	+10.61	2.72	Persian shāhīn-i tarāzū, "the balance beam"
Alshain (Beta Aql)	19.921	+6.41	3.71	Same Persian "balance" root as Tarazed
Okab (Zeta Aql)	19.090	+13.86	2.99	Arabic dhanab al-'uqāb, "tail of the eagle"; renamed Okab by the IAU in 2018
Antinous (Theta Aql)	20.188	-0.82	3.23	Named by the IAU in 2024 for Ptolemy's now-obsolete sub-constellation, below
Delta Aql	19.425	+3.11	3.36	Bayer letter only
Lambda Aql	19.104	-4.88	3.43	Bayer letter only

Distances and spectral types for Tarazed, Alshain, and the other named stars in this table aren't included here because they weren't independently verified for this page — better a gap than a guess.

Altair up close

Altair is one of the fastest-spinning naked-eye stars known. It completes a full rotation in roughly 7 hours 46 minutes — for comparison, the Sun takes about 27 days — and that speed physically distorts the star. Interferometric measurements with the CHARA Array, a network of linked telescopes on Mount Wilson that combine their light to resolve detail no single telescope could, show Altair's equatorial diameter running about 22–24% larger than its polar diameter: it isn't a sphere, it's a measurably oblate spheroid, flattened by its own spin. In 2006–2007, astronomers assembled the first direct image of that shape rather than only inferring it.

Altair is also close. At about 16.7 light years, it's one of the nearest stars visible to the naked eye from Earth, and by a wide margin the nearest of the three Summer Triangle stars — Vega, at 25 light years, is the next closest, and Deneb, well over a thousand light years off, isn't in the same category at all.

Aquila is one of Ptolemy's 48 constellations in the Almagest. In Greek and Roman mythology, the eagle is Zeus's own bird, the carrier of his thunderbolts — but it's also tangled up in at least two love stories. In the more famous one, the eagle (Zeus himself transformed, according to Ovid, or an eagle Zeus simply sent, according to other sources) snatches the beautiful Trojan boy Ganymede to become cup-bearer to the gods on Olympus; Ganymede himself is the neighbouring constellation Aquarius, and old star charts show Aquila swooping down toward him. In a second story, told by Hyginus, the eagle and the swan are linked directly: Zeus fell for the goddess Nemesis, and when she resisted, he turned himself into a swan while Aphrodite, disguised as an eagle, pretended to chase him. Nemesis sheltered the fleeing swan — and found herself in Zeus's arms. To commemorate the trick, Zeus set both birds in the sky as Cygnus and Aquila (compare Cygnus's own telling of that myth).

The southern part of Aquila used to be its own constellation. Ptolemy subdivided it into Antinous, six stars from 3rd to 5th magnitude visualized on some old star charts as a young man held in the eagle's claws — a Roman-era addition honouring Hadrian's companion Antinous, not a classical Greek figure. The constellation fell out of official use, but its stars were simply folded back into Aquila; one of them, Eta Aquilae, is among the brightest Cepheid variable stars in the sky, its variability discovered in 1784 by the English amateur astronomer Edward Pigott. In 2024, the IAU revived the old name for one last star: Theta Aquilae is now officially Antinous.

Altair carries a second, entirely separate mythology in East Asia, and it earns the space here in full. In Chinese folklore, Vega is Zhinü, the Weaving Girl — granddaughter of the Celestial Emperor and a maker of beautiful silk — and Altair is Niulang, a humble cowherd, flanked by the two stars either side of him (Tarazed and Alshain) who represent the couple's children. The two fell in love, married, and began neglecting their heavenly duties; to put a stop to it, the Celestial Emperor separated them with a stroke of a hairpin that became the Milky Way. Ever after, the couple has been allowed to meet only once a year, on a single night when a flock of magpies forms a bridge across the Milky Way with their wings, letting Zhinü cross to Niulang.

That reunion is celebrated as Qixi, the Double Seventh Festival — held on the seventh day of the seventh month of the Chinese lunar calendar (see Lunar Calendar for how that calendar is reckoned), which usually lands in August on the Gregorian calendar and is sometimes called the Chinese Valentine's Day. It's worth noticing that this story and the older Arabic tradition arrive at oddly parallel imagery from opposite directions: Arab astronomers saw Vega and Altair as a matched pair of birds of prey, one folded and diving, one outstretched and soaring (see Lyra); Chinese folklore saw the same two stars as a separated husband and wife. Two unrelated traditions, looking at the same two bright points on either side of the Milky Way, both built a relationship out of them.

For Vega's other stories — its long turn as pole star, its role defining the zero point of stellar magnitude, and its status as the first star ever photographed — see Lyra.

• NGC 6709, an open cluster about 3,500 light years away, magnitude 6.7 — faint but reachable in binoculars from a dark site, five degrees southwest of Zeta Aquilae.
• NGC 6741 ("Phantom Streak Nebula"), a small, faint planetary nebula roughly 7,000 light years away, magnitude 11.5 — a telescope target, not a binocular one.

Date	Event
c. 275 BCE	Aratus's Phaenomena describes the eagle.
c. 150 CE	Ptolemy catalogues Aquila in the Almagest and subdivides its south into the now-obsolete Antinous.
1784	Edward Pigott discovers the variability of Eta Aquilae, one of the sky's brightest Cepheids.
1930	The IAU adopts Eugène Delporte's precise boundaries for the 88 constellations, fixing Aquila's borders on the sky.
1992	Rho Aquilae's own proper motion carries it across the border into neighbouring Delphinus.
2018	The IAU formally names Zeta Aquilae "Okab."
2024	The IAU names Theta Aquilae "Antinous," reviving Ptolemy's old sub-constellation.

• Cygnus — the Summer Triangle, explained in full.
• Lyra — Vega, the Weaver Girl's other half.
• Delphinus — the nearest neighbouring figure, and the destination of Rho Aquilae's border crossing.
• Lunar Calendar — how the date of Qixi is actually reckoned.