Sunday, January 24, 2010
The Southern Cross from Other Planets
The Cross didn't look that much different, but how far would you have to go for the skies to begin to look strange? What would you see from the surface of alien planets?
To answer that I've used Celestia again, to travel to exoplanet locations and see what their skies would look like. As most of these are "hot Jupiters" the concept of surface is problematic, and I've shown the view from orbit.
The Southern Cross from Epsilon Eridani B, 10.5 light years away. The Cross is very distorted, but still recognisably a cross. Gacrux is only 88 light years away, compared to 320 Ly for Acrux, 352 Ly for Mimosa (beta Crucis) and 364 for delta Crucis, so Gacrux moves the most. Rigel Kentaurus (alpha Centauri) at only 4 Ly moves out of the frame.
The Southern Cross from Gliese 674 b, 14 light years away. The cross is very distorted now, despite being not much further away then Epsilon Eridani b.
The Southern Cross from the super earth Gliese 581 d, 20 light years away. The Cross is unrecognisable. In fact, the only recognisable part of any constellation from Gliese 581 d (assuming the atmosphere was transparent enough for you to see through) is the head of the constellation Scorpio, all else is distorted beyond recognition.