Antares
From Wikipedia, the free encyclopedia
- This article is about the star. For other meanings, see Antares (disambiguation)
| Observation data Epoch J2000 | |
|---|---|
| Constellation | Scorpius |
| Right ascension | 16h 29m 24s<ref name="simbad">SIMBAD Astronomical Database. Results for CCDM J16294-2626A/B. Retrieved on 2006-10-23.</ref> |
| Declination | -26° 25′ 55″<ref name="simbad" /> |
| Apparent magnitude (V) | 1.09<ref name="simbad" /> |
| Characteristics | |
| Spectral type | M1.5Iab-b / B2.5V<ref name="simbad" /> |
| B-V color index | 1.87 |
| U-B color index | 1.34 |
| Variable type | LC-type |
| Astrometry <tr valign=top><td>Radial velocity (Rv)</td><td>−3.4<ref name="simbad" /> km/s</td></tr><tr valign=top><td>Proper motion (μ)</td><td> RA: −10.16<ref name="simbad" /> mas/yr Dec.: −23.21<ref name="simbad" /> mas/yr </td></tr><tr valign=top><td>Parallax (π)</td><td>5.40 ± 1.68 mas</td></tr><tr valign=top><td>Distance</td><td>approx. 600 ly (approx. 190 pc)</td></tr><tr valign=top><td>Absolute magnitude (MV)</td><td>−5.28</td></tr> | |
| Details | |
| Mass | 15-18 M☉ |
| Radius | 700 R☉ |
| Luminosity | 65,000(bolometric) L☉ |
| Temperature | 3,500 K |
| Metallicity | - |
| Rotation | - |
| Age | - years |
| Other designations | |
| α Scorpii,<ref name="simbad" /> 21 Sco,<ref name="simbad" /> Cor Scorpii, Kalb al Akrab, Scorpion's Heart, Vespertilio, HR 6134,<ref name="simbad" /> CD -26°11359,<ref name="simbad" /> HD 148478,<ref name="simbad" /> SAO 184415,<ref name="simbad" /> FK5 616,<ref name="simbad" /> WDS 16294-2626, CCDM J16294-2626A/B,<ref name="simbad" /> HIP 80763.<ref name="simbad" />
| |
| Database references | |
| SIMBAD | data
|
Antares (α Scorpii / Alpha Scorpii) is the brightest star in the constellation Scorpius and one of the brightest stars in the nighttime sky. Along with Aldebaran, Spica, and Regulus it is one of the four brightest stars near the ecliptic. The similarly colored Aldebaran lies almost directly opposite Antares in the Zodiac.
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[edit] Antares in ancient cultures
Antares' name derives from the Greek Αντάρης, meaning "(holds) against Ares (Mars)", due to the similarity of its reddish hue to the appearance of the planet Mars. This distinctive coloration has made the star an object of interest to many societies throughout history. According to ancient Arab tradition, Antares is the warrior-poet Antar's star. Many of the old Egyptian temples are oriented so that the light of Antares plays a role in the ceremonies performed there. Some writers claim that it is the "lance star" referred to in the Biblical book of Job. Antares was also known as Satevis in ancient Persia and was one of the four "royal stars" of the Persians around 3000 BC. It is also known as Jyeshtha in ancient India. In the religion of Stregheria, Antares is a fallen angel and quarter guardian of the western gate. In astrology Antares is one of the Behenian fixed stars and has the symbol 
. antares is the 15th brightest star that we know of.
[edit] Properties
Antares is a class M supergiant star, with a diameter of approximately 1.33 × 109 km, or if in place of our sun, it would slightly more than encompass the average orbit of Mars. Antares is approximately 600 light years from our solar system. Visually, its luminosity is about 10,000 times that of the Sun but overall, taking into account that the star radiates a considerable part of its energy in the infrared part of the spectrum the luminosity equals roughly 65,000 times that of the Sun. The mass of the star is calculated to be 15 to 18 solar masses. Its large size and relatively small mass give Antares a very low density.
The best time to view Antares is on or around May 31 of each year, when the star is at "opposition" to the Sun. At this time, Antares rises at dusk and sets at dawn, and is thus in view all night (this of course depends entirely on your own position on the globe). For approximately two to three weeks on either side of November 30, Antares is not visible at all, being lost in the Sun's glare; this period of invisibility is longer in the Northern Hemisphere than in the Southern Hemisphere, since the star's declination is a few degrees south of the ecliptic.
[edit] Companion star
Antares has a hot blue companion star (Antares B) at a distance of about 2.9″. Although it is 5th magnitude, it is normally difficult to see because of Antares' glare, but can be observed with a small telescope for a few seconds during lunar occultations while Antares itself is hidden by the Moon; it was discovered during one such occultation on April 13 1819. The orbital period is 878 years.
[edit] Position on the ecliptic
Antares is one of the 4 first magnitude stars which lie within 5° of the ecliptic and therefore can be occulted by the Moon and rarely by the planets. On 17 Nov 2400 Antares will be occulted by Venus.
Of the 21 first-magnitude stars, Antares now lies further in angular distance from any first-magnitude star than any other first magnitude star, i.e. you could draw the largest circle centered around Antares without including any other first-magnitude star inside that circle. The nearest first-magnitude star to Antares is Alpha Centauri, lying approximately 39°6.75′ away. The high proper motion of Alpha Centauri is gradually increasing this angle. Before about March 2000, Achernar and Fomalhaut held this distinction.
[edit] Antares in popular culture
[edit] Trivia
- Antares is a symbol for the Swedish historical province of Småland.
- In 1971, the crew of Apollo 14 named their lunar module after the star.
- A song in beatmania IIDX 11 (IIDX RED), "Piano Concerto No. 1 'Scorpion Fire'" (ピアノ協奏曲第1番"蠍火" Piano Kyousoukyoku Dai-ichiban "Sasoribi"?), is named after the star; the subtitle refers to the star's superlative brightness as α Sco, thereby being the figurative "fire" of Scorpius. It is also referred to by other names, most of them translations of "Sasoribi" (蠍火); IIDX RED's music selection wheel uses "Anti-ares".
- Antares is the name of the restaurant atop Reunion Tower, the largely illuminated sphere usually visible in most pictures of Dallas, TX, US.
- PC Game Master of Orion II: Battle at Antares (MOO2) featured a race of intergalactic beings named Antarans whose homeworld Antares was sealed in another dimension by a rival intergalactic race
[edit] Fiction
- See Antares in fiction.
[edit] External links
- http://www.co-intelligence.org/newsletter/comparisons.html - A comparison of the size of Antares to other solar objects.
[edit] References
an:Antares ca:Antares da:Antares de:Antares es:Antares fr:Antarès gl:Antares ko:안타레스 it:Antares he:אנטארס lt:Antaris nl:Antares ja:アンタレス pl:Antares pt:Antares ru:Антарес sk:Antares fi:Antares sv:Antares tr:Antares zh:心宿二
