One of the most dramatic sights through a modest-sized telescope and at low-powers is the appearance of a carbon star
within the field of view, for such stars stand out on their own thanks to their very rich reddish colouration and
appearance and in spite of the hundreds of stars that may surround each such example.
Carbon stars represent cooled supergiants and some white dwarfs which are surrounded by a cloud of dust comprised of
various forms of carbon (ex. CH, CN, C3 and SiC2). They are characterized with a surface temperature ranging between
2000 and 3000 degrees Kelvin and are invariably variable in their magnitude (periods in excess of 100 days) and with
some exhibiting fluctuations by as much as six magnitudes!
Perhaps the best known carbon star is Betelgeuse (á-Orionis), a cool supergiant which is not only one of the brightest
stars gracing our skies (M(v) = 0.58) but is also one of the closest to our solar system (427 + 76 light-years).
Of the nearly six thousand stars catalogued by Stephenson,
there are over 100 examples whose magnitude is easily within the reach of binoculars and/or very modest amateur
telescopes for visual observation.
Proper Star Name: N/A Bayer Letter: T Draco Hipparcos Catalog: HIP 87820 SAO Catalog: N/A Luminosity 00000 + 00000 x Sun Distance: N/A RA / Dec: 17h 56m 23s / +58° 13' 06" B-V Color Index: +2.55 mag Magnitude: 10.0 |
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Date: Jul 10-11, 2007 22:45 - 00:50 UT+3 Location: Athens, Greece Equipment: AP 160 f/7.5 StarFire EDF AP1200GTO GEM SBIG ST-2000XM SBIG CFW10 Integrations:
Temperatures:
Software: CCDSoft V5.00.182 CCDSharp V1.4 AIP4Win V2.1.19 Photoshop CS2 |