How to form clumps in the intermediate ranges of massive protoplanetary disks? Could these later be planets?
A model that needs fewest parameters to explain a scenario is favourable. The fact that mm-size dust grains (chondrules) are present in the entire solar system brings rise to the question, whether all bigger solid objects are a collection of chondrules.
Planets are ubiquitous in the Milky Way. Therefore, building them must be straightforward, right? Not at all!
Earth’s atmosphere is about 100 times less massive than Venus’ atmosphere. This gave rise to the idea that Earth had a more massive atmosphere, which got then depleted by impacts. This Astrobite discusses what would have been the optimal impactor size.
By combining galaxy formation histories and planet formation models, we can estimate the number of potential civilizations in our Universe.
Why do some planets slightly more massive than Earth have gas envelopes, while others don’t?