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| # Alpha (α) Tauri | |
| Aldebaran |
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| Red Giant Star |
| Right Ascension | 4h 35m 55.2s | Best Seen | 12/1 - 4/15 |
| Declination | 16° 30' 33" | Magnitude | 0.87 |
| Constellation | Taurus | ||
| Actual | Compared to Sun | |
| Distance | ~65 ly | -- |
| Actual Brightness | -- | 141 |
| Surface Temperature | ~6,700 °F | ~0.69 |
| Diameter | -- | 44 |
| Mass | -- | -- |
| Surface Gravity | -- | -- |
| Surface Composition (by mass) | 74% hydrogen 24% helium 2% everything else |
same |
| Spectral Type | K5 III | G2 V |
| Density (gram/cubic cm) | -- | -- |
What To Look For Through The Telescope
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Recommended eyepiece: 24mm or 40 mm.
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When people look through the telescope a bright reddish-orange point of light should be seen.
Aldebaran Information:
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Aldebaran is the 9th brightest star in the Northern Hemisphere’s night sky (14th brightest star when including the Southern Hemisphere’s bright stars).
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This star is the eye of constellation Taurus the Bull.
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Aldebaran may have a companion 1.35 AU’s away, as massive as 11 Jupiters. This has yet to be confirmed. (1 AU, or Astronomical Unit, is 93 million miles, the distance between the Sun and Earth.)
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References
| Item | Updated | Notes |
| Coordinates | 2003-01-06 | tweaked a bit |
| Distance | 2003-01-06 | OK with Scott’s The Flamsteed Collection and SIMBAD |
| Actual Brightness | 2003-01-06 | previously “125" – BUT Flamsteed says 141 |
| Surface Temperature | 2003-01-06 | previously “5,600 ºF” – BUT Source says 4000 K (~6,700 ºF) http://www.eso.org/outreach/eduoff/catchastar/cas projects/uk_aldebaran_1/ At anyrate, 5,600 °F is too cool, according to Flamsteed: K stars lowest temp is 5,800 °F |
| Diameter | 2005-06-02 | previously said 32 millions miles / 40 times bigger than sun – BUT can find not support, plus, at 140 times more luminous, roughly same temp, should radius only be sqrt(140) times bigger plus more for being cooler? Paper from Astron. & Astrophys. collated all the angular measurements and got an average value of 19.96 milliarcsec for the uniform disk diameter and 20.58 millarcsec for limb darkened value. This gives a diameter of 44Rsun with an error of 0.9 Rsun. http://www.edpsciences.org/articles/aa/abs/2005/13/aa1765/aa1765.html |
| Mass | -- | |
| Surface Gravity | -- | |
| Surface Composition | 2003-01-06 | OK for all stars |
| Spectral Type | 2003-01-06 | OK with Flamsteed and SIMBAD |
| Density | 2003-01-06 | previously said 0.00005 times Sun – BUT can find no evidence for this |
| Other Information | 2003-01-06 | previously: “There is a red dwarf companion star 60 billion miles away, or about 650 times the Earth-Sun distance.” – BUT cannot find info that there IS a companion, but that there might be one, see http://www.extrasolar.net/mainframes.html |