Rethinking the Planet Formation Deadline
Observational biases may significantly underestimate the lifetime of protoplanetary disks.
Migrating Super-Earths vs. Terrestrial Planets
Of all the kinds of planets we’re finding around other stars—hot Jupiters and mini-Neptunes and those dubiously called “Earth-like”—super-Earths orbiting close to their stars are among the most abundant. While planets so close to their stars are poor candidates for habitability, they are important to understanding the possibility of other habitable planets in these seemingly common systems.
Can Icelines Explain Uranus and Neptune?
A new hypothesis posits that the ice giant planets formed between the CO and N2 icelines in the Solar System’s protoplanetary disk.
Mercury’s surprising density: What about magnets?
A new model explains Mercury’s major density with magnetism.
How Easily Do Carbon-Rich Planets Form?
A new model simulates the composition of growing planetesimals in an evolving protoplanetary disk. The model predicts that carbon-rich terrestrial planets can form more easily than previously thought.
An Exoplanet’s Fast Spin
Planets in the Solar System with a higher mass spin faster than lower-mass planets. But what about planets in other systems? The authors of this paper make the first measurement of an exoplanet’s spin to compare its spin and mass to Solar System planets.