Image description:
Even if we put a planet to orbit this star
at 4 AU, the problem comes from the invisible part of light, called
ultra-violet which is very strong for this type of stars (spectral
type A).
Also, strong stellar winds could damage the atmosphere
and make UV rays even more powerful in their destruction. Maybe
some bacteria could live below planet's surface. Even if life starts
below the surface, the star will become red giant in next 1 billion
years, which is not enough for life to develop.
This is the main
reason why O, B and A spectral type stars are excluded from the "search
for life". It would take 5 years 3 months for our Earth sized
planet to finish one orbit around this star, at approx. speed of
22,6 km/sec.
On this picture, we see the dawn at Altair system.
"Moon" and some planets can bee seen on the sky. |
