dimitar sasselov

Aliens may only be at the prehistoric time.
This is also the reason why we cannot find traces of aliens in this vast universe.
Reopen the debate about Pluto
Pluto still has a chance to be admitted into the solar system's planetary family after receiving a majority of votes
Astronomers confused because of the giant version of the earth
The Kepler space telescope detected a planet with a hard surface like the globe, but its size was 17 times larger than our planet.