ALDEBARAN (ALPHA (α) TAURI)
RED GIANT STAR
Right Ascension:
4h 35m 55.2s
Best Seen:
12/1 - 4/15
Declination:
16º 30' 33"
Magnitude:
0.87
Computer File:
aldebara
Constellation:
Taurus
Actual
Compared to Sun
Distance
65 l.y.
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Actual Brightness
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141
Surface Temperature
6,700 ºF
0.69
Diameter
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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)
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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.)
Item
Updated
Notes
Coordinates
01-06-2003
tweaked a bit
Distance
01-06-2003
OK with Scott’s The Flamsteed Collection and SIMBAD
Actual Brightness
01-06-2003
previously “125" – BUT Flamsteed says 141
Surface Temperature
01-06-2003
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 ºF is too cool, according to Flamsteed: K stars lowest temp is 5,800 ºF
Diameter
01-06-2003
06-02-2005
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 anglular measurements and got an average value of 19.96milliarcsec for the uniform disk diameter and 20.58 millarcsec for limb darkened value. This gives a diameter of 44Rsun with an error of 0.9Rsun. http://www.edpsciences.org/articles/aa/abs/2005/13/aa1765/aa1765.html
Mass
Surface Gravity
Surface Composition
01-06-2003
OK for all stars
Spectral Type
01-06-2003
OK with Flamsteed and SIMBAD
Density
01-06-2003
previously said 0.00005 times Sun – BUT can find no evidence for this
Other Information
01-06-2003
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