Dr. David Nesvorny has published the result of 6,000 simulations that suggest that there was a fifth giant planet with a mass similar to that of Uranus and Neptune which at a certain point got lost in interstellar space.
Eris is a dwarf planet whose discovery led to the creation of the new category of dwarf planets with the “demotion” of Pluto. New observation allowed astronomers to establish that Eris and Pluto have almost the same exact size.
Kepler-16b, this is the name of this planet distant about two hundred light years from Earth and discovered by NASA’s Kepler space telescope, is cold and at least partially gaseous, more or less the size of Saturn. What it has in common with Tatooine is the fact that it orbits two stars so there are astronomers who began to call it informally with that name.
The Mars Rover Opportunity reached the Endeavour crater about three weeks ago after a long journey and it’s already making discoveries that are very interesting from a scientific point of view. In fact the first analysis confirms that the environmental conditions of ancient Mars were favorable to life.
Accoring to a research made by an international team of scientists Mars small size might be the result of Jupiter moving towards the Sun while it was forming, which might have absorbed part of the matter present in the orbit of what then coalesced into the red planet.