Barnard's star in the constellation Ophiuchus, after the Alpha Centauri system, is the nearest star to the Sun at a distance of 1.83 parsecs or 5.97 light years. Located at RA(2000) = 17h 57.9m and Dec(2000) = +4d 41' in the constellation Ophiuchus, it is classified as an M3.8 Main Sequence star with a luminosity about 0.00045 that of the Sun and an apparent visual magnitude of +9.56. From the Palomar Digital Sky Survey you can extract an image of the field where the star ought to be, but the Palomar Survey was taken so long ago that Barnard's Star has not yet arrived at its epoch 2000.0 position in the Palomar photograph!
If it were located where the Sun is from the Earth, it would be a very red sun, and the Earth would be in permanent deep freeze with no liquid water. Our Sun has an apparent magnitude of -26, and Barnard's Star is about 8.4 magnitudes fainter or -17.6 at the same distance from the Earth. The Full Moon is at -12.3 magnitudes so Barnard's Star as our 'new Sun' would be about 100 times brighter than the Full Moon.
In a 4.5-inch telescope, you should be able to see this star IF you have the proper finding charts for it for the current year. It moves 10 arc seconds per year so for a faint star like this, in a rather crowded field of other similar faint stars, it will be easy to loose it.
For more information visit the SEDS Page and Jack Schmidling's Page.
Copyright 1997 Dr. Sten Odenwald
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