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?
Planets in binary star systems can receive a sizable amount of water from asteroids getting perturbed out of their orbits
More than 50 years ago, a Norwegian astronomer named Sjur Refsdal outlined an interesting new method for calculating the Hubble constant. Last November, astronomers found the perfect test case.