How to see it
Altair is the 12th brightest star, and so it is respectably bright (apparent magnitude 0.76 or 0.77), a fact that increases your likelihood of spotting it in summer or autumn skies. What’s more, Altair is flanked by two other stars, Tarazed and Alshain. When you see them, you might think of these stars as walking three abreast and arm-in-arm across the heavenly sphere.
Altair is also known as Alpha Aquilae, and it is the brightest star in the constellation Aquila the Eagle.
What’s more, stargazers know Altair as part of an entirely different and much-larger – but very recognizable – pattern. Altair is the southern apex of the Summer Triangle, which is also composed of the stars Vega and Deneb.
On the first of June, Altair rises about 90 minutes after sunset, as viewed from mid-north latitudes. By the end of September it approaches the meridian as night falls. By the end of the year, late-night observers will miss it altogether as it sets less than three hours after the sun.
Many depictions place Altair as the head or neck of an eagle with outstretched wings. The tips of the wings are formed by the Theta and Zeta stars of the constellation Aquila the Eagle, with the tail being Lambda. Once visualized, Aquila the Eagle can be seen flying eastward through the Milky Way, apparently about to devour the tiny constellation Delphinus, the Dolphin.
History and myth
The name Altair is Arabic in origin and has the same meaning as the name of the constellation Aquila in Latin; that is, they both mean simply ‘eagle.’ In classical mythology Aquila, and by extension Altair as well, was an eagle favored by Zeus. He played a part in numerous myths, including the abduction of Ganymede in which a young boy (Ganymede) is carried off to Mount Olympus on Zeus’ command to become the cupbearer to the gods. In another myth Aquila is the eagle that torments Prometheus, and is shot with a poisoned arrow by Hercules.
In India, Altair with its two flanking stars, Beta and Gamma (Tarazed and Alshain), are sometimes thought to be the celestial footprints of the god Vishnu.
Altair is separated from the similar-looking (but brighter) star Vega in the constellation Lyra by the great starlit band of the Milky Way. In Asia, this hazy band across our sky is known as the Celestial River. One story common in China, Japan and Korea a young herdsman (Altair) who falls in love with a celestial princess (Vega), who weaves the fabric of heaven. The princess became so enamored of the herdsman that she neglects her weaving duties. This acts enrages the princess’s father, the Celestial Emperor, who decrees that the herdsman must stay away from his daughter, on the opposite side of the River. The Emperor finally listened to the princess’s pleas, however, and allowed the herdsman to cross the Celestial River once per year, on the seventh day of the seventh month.
In Japan, Altair is Hikoboshi, and Vega is Orihime (or Tanabata). If it rains on the day of the festival of Tanabata, it is said to be Orihime’s tears because Hikoboshi could not navigate the treacherous waters of the Celestial River.
Science
Altair is only 16.8 light-years away from Earth, making it one of our nearer stellar neighbors. If it were substituted for our sun, at the distance the sun is now, life on Earth would be doomed, as Altair shines with 11 times the sun’s visible light. However, with a surface temperature of about 7550 K degrees, Altair isn’t much hotter than the sun (at 5800 K). Higher temperatures usually reveal greater mass, at least for Main Sequence stars, and Altair is thought to be in excess of 1.7 times the mass of our sun.
Two other things that make Altair distinctive. The first is its rapid rotation – this star requires only about 10 hours to spin once on its axis, in contrast to 24 hours for our Earth to spin or roughly a month for our sun. In other words, this mighty star spins on its axis more rapidly than Earth! This rapid rotation tends to flatten the star a bit, much as a pizza crust flattens as it spins. Estimates are roughly that Altair’s flattening is about 14 percent. The sun also is an oblate spheroid, although its flattening is difficult to measure due to the low rotation rate.
The second fact that makes Altair stand out is that it is a weak and unusual variable star with as many as 9 different rates of brightness waxings and wanings. The brightness variations are too small to measure without sensitive instruments, but likely are related to the high rotation rate.
The position of Altair is RA: 19h 50m 47.0s, dec: +08° 52′ 06″
i wanted to know what the SURFACE TEMPERATURE was, not the myths and the other boring stuff that grown-ups want. oh, well. i guess i will have to go to another website…
Dear Ms. Hogg, sorry to have disappointed you. In fact, however, the article does state the surface temperature at 7550 kelvins, which is about 13,130 degrees Fahrenheit. Kelvins are degrees in the Absolute system that those boring grown up scientists use. How’s your sister, Ura? (Or was Ura just one of those myths, too?)
this is helpful, thanks c: bahaha
altair is from assasins creed
Assassins Creed is a video game. Altair is a name for the star that has been in use for hundreds of years.
Thank you. I appreciate the time and knowledge that you share with us by creating this site. I found your information invigorating, we live in such a great time of illumination and insight into what is all around us, above and below us … not to mention what is inside of us. We all are made of what the stars are made of.
Thanks, Lisa. Not only are we “star stuff” as Carl Sagan used to say, but almost every atom in your body is at least 5 billion years old, and some date to within a few minutes after the Big Bang, 13.7 billion years ago. Pretty amazing stuff.
thanks this was really helpful i loved the myth
Hunter, glad you liked it.
This is pretty neat and not to mention helpful. I was wondering where the Eagle was so this helped.
I thought that Altair meant “the flying one” in Arabic? Flying does not always mean eagle but it could loosely translate to eagle.
The myth however was most interesting to me. The myth correlates into Chinese and Vietnamese constellation lore.
Overall, thank you for taking the time to showcase this information.
Aeros,
Glad to be of service. My understanding (from Star Names by Richard Hinckley Allen) is that the name is derived from the Arabic phrase for the name of the constellation, which some have translated as the “Soaring Eagle.” It may be that the phrase, the “Flying one” was an idomatic reference to an eagle in ancient Arabic, although I certinly am not an expert in that field.
Rana, glad it works for you. Hope you keep coming back.
This site was really helpful. Not only WAS THE SURFACE TEMPATURE in the article, but it also had some intresting facts I could use for my science project! Thanks! The thing is, I just need to know what kind of star it is. Thank you!
Dee,
Not sure what you mean by what “kind” of star, but Altair is larger, hotter, brighter and more massive than our Sun. It’s bluish tinge is characteristic to the higher temperature, as very hot stars are blue, medium stars like our sun yellowish, and less hot stars are red. The spectral classification is A7V, where the A stands for the “A” class in the Harvard spectral sequence, OBAFGKM, 7 the subclass, and the V is the Roman numeral 5, which indicates that Altair is a “normal” or “Main Sequence” star. Some references list it as A8V, bu tthe difference is minor.
My name is Altairs and of course I was named from the star Altair. Im always curious about the star and what it means. I think its the best name in the world cause I think Im the only one with the name. Anyway, when I try to find out what I want to know about the star itss hard to pinpoint the information that Im looking for. When I went on your website i found alot of information and answers that I have been looking for in years. Thats for the great information.
Doubtless you know, but others may not, that Altairis (Anne Francis) was the female lead in the 50s scifi classic, “Forbidden Planet,” set on a planet (Altair IV) orbitting Altair.
I take my 3 year old daughter for a walk every night armed with a $10 astronomical laser pointer. The first asterism she got introduced was the summer triangle.. After 2 months of nightly walks, she can now identify vega, daneb, altair, northern cross, square of pegasus, cassiopea, andromeda, perseus, arcturus and antares. I am always looking for making it interesting with stories to connect the dots.. The story about altair and vega will be on the cards this week :-)
Glad to hear it. Don’t feel shy about asking questions or making requests. I cannot promise to respond to everything immediately, but I will try.
Thank you so much for this! I’m doing a report on this star and all this information is extremely helpful! especially the history, not many sites put up information on that. :D
Perhaps you could include Altair’s apparent magnitude? I know it is bright, but if I had a number specifying exactly how bright, I might better understand why Altair and Tarazed make such a pretty pair. Thanks.
It’s apparent magnitude is 0.76 or 0.77, depending on whose data you rely.