What would a laser-powered sail starship look like from space?

Larry Klaes (lklaes@bbn.com)
Mon, 18 Oct 1999 16:25:49 -0400

If a starship composed of a 1,000 kilometer-wide sail being pushed at nearly the speed of light by a very powerful laser beam in the terrawatt range was headed towards Earth - and was, say, less than 1/2 a light year away - how would it appear from our planet in various spectrums and wavelengths, especially optical?