Our hypothetical planet is located at 2
AU. The main problem comes from the invisible part of light, called
ultra-violet which is very strong for this type of stars (spectral
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". On this picture, we see the dawn at Sirius system.
Haze is due to the dust particles of this dead and burnt world.
Because of Sirius B, we couldn't move our hypothetical planet at
3 or 4 AU (better location) since Sirius B would disrupt this
planet's orbit and kick it out of the system.