Aarhus Universitets segl

SAC seminar - Daves Hoszowski: Puffed-up planets

Oplysninger om arrangementet

Tidspunkt

Tirsdag 3. september 2013,  kl. 11:00 - 12:00

Sted

1525-323

Speaker: Daves Hoszowski, NBI, University of Copenhagen, Denmark

Title: Puffed-up planets

Abstract:

In the last decade over 900 exoplanets have been confirmed and over 2000 candidates from the Kepler mission await confirmation, with a low false-positive rate for detection. It allows planetary scientist to work on theories of planetary formation and evolution. However, the variety of planets is striking; ranging from rogue planets, CFBDSIR 2149-0403, to multiple planet systems, KOI-94 (b,c,d,e). One type of planets, are the puffy planets, or inflated planets. These are similar to the hot-Jupiters in mass and proximity to a star, but their densities are very low, some even lower than cork.

To understand planetary formation and evolution; we need to investigate how these gaseous planets can in inflate in close-in orbits. Stellar irradiation does not inflate the planets enough, thus requiring support from other models such as tidal heating and enhanced atmosphere. However these models seem to lack observational evidence supporting them, i.e. tidal heating requires an eccentric orbit, but only a few close-in orbital planets are eccentric. So, the model might explain a few cases, but not all of them.