Over the past decade the study of planetary debris at white dwarfs has become an increasingly exciting area. Observations of this debris have allowed us to make unique discoveries about the chemical composition of extrasolar rocky planets, as well as revealing the endpoints of the evolution of planetary systems very similar to our own…
Those of us who love astrobiology get really worked up about the lack of Earth-sized exoplanets found at Earth-like distances from their stars. All we want, we who hope for lots of extraterrestrial life, is a bunch of Earth-like planets doing Earth-like things so we can feel better about the odds for lots of Earth-like life in the universe.
There does not seem to be enough mass in protoplanetary disks to build the planetary systems we’ve detected. The solution: planet formation might start sooner than previously thought.
Observational biases may significantly underestimate the lifetime of protoplanetary disks.
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.
A new hypothesis posits that the ice giant planets formed between the CO and N2 icelines in the Solar System’s protoplanetary disk.
A new model explains Mercury’s major density with magnetism.
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.
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.
How do giant planets affect the water content of rocky planets in habitable zones? Astronomers have run new planet formation simulations to try to answer this question.