posted by Paula .
If Deneb and Rigel were located at alpha Centauri's distance from earth, how would they appear?
Deneb and Rigel would appear much brighter than they are. Actual distances are:
alpha Centauri: 4.37 light years
Deneb: 1425 light years
Rigel: 860 light years
If you moved Deneb to the alpha Centauri distance, it would appear (1425/4.37)^2 = 106,000 times brighter than it is now. Rigel would be 39,000 times brighter. Figure out what that would do to the apparent magnitues, and compare them to other bright sources in the sky. Both would certainly be brighter then Venus at its brightest.