Delta Sagittarii
From Infogalactic: the planetary knowledge core
 Location of δ Sagittarii (circled) |
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| Observation data Epoch J2000.0 Equinox J2000.0 |
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|---|---|
| Constellation | Sagittarius |
| Right ascension | 18h 20m 59.64354s[1] |
| Declination | −29° 49′ 41.1659″[1] |
| Apparent magnitude (V) | +2.70[2] |
| Characteristics | |
| Spectral type | K3 III[3] |
| U−B color index | +1.55[2] |
| B−V color index | +1.38[2] |
| Astrometry | |
| Radial velocity (Rv) | –19.9[4] km/s |
| Proper motion (μ) | RA: +32.54[1] mas/yr Dec.: −25.57[1] mas/yr |
| Parallax (π) | 9.38 ± 0.18[1] mas |
| Distance | 348 ± 7 ly (107 ± 2 pc) |
| Absolute magnitude (MV) | −1.99[5] |
| Details | |
| Other designations | |
Delta Sagittarii (Delta Sgr, δ Sagittarii, δ Sgr) is a double star[6] in the southern zodiac constellation of Sagittarius. It has the traditional names Kaus Media, Kaus Meridionalis, and Media.The apparent visual magnitude of this star is +2.70,[2] making it easily visible to the naked eye. Parallax measurements place the distance at roughly 348 light-years (107 parsecs) from Earth.[1]
This is a giant star with a stellar classification K3 III.
It has three dim companions:[citation needed]
- a 14th magnitude star at a separation of 26 arcseconds,
- a 15th magnitude star at a separation of 40 arcseconds, and
- a 13th magnitude star at a separation of 58 arcseconds from the primary.
It is not certain that these stars form a physical system or whether they are merely aligned by chance.
Name and etymology
- The names Kaus Media, Kaus Meridionalis, and Media, are come from the Arabic قوس qaws 'bow' and Latin media 'middle'.
- This star, together with :
- In the catalogue of stars in the Calendarium of Al Achsasi al Mouakket, this star was designated Thanih al Waridah, which was translated into Latin as Secunda τού al Warida, meaning second going ostrich.[10]
- In Chinese, 箕 (Jī), meaning Winnowing Basket, refers to an asterism consisting of δ Sagittarii γ Sagittarii, ε Sagittarii and η Sagittarii. Consequently, δ Sagittarii itself is known as 箕宿二 (Jī Sù èr, English: the Second Star of Winnowing Basket.)[11]
- In the Hindu system of astrology, this star is also called "Purvashada Nakshatra".
See also
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 2.0 2.1 2.2 2.3 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 6.0 6.1 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ skywatchers Archived May 17, 2007 at the Wayback Machine
- ↑ 9.0 9.1 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ (Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 5 月 11 日
