Extrasolar Planets: November 2020

Ice shell dynamics are an important control on the habitability of icy ocean worlds. Here we present a systematic study evaluating the effect of temperature-dependent material properties on these dynamics.

We present simulations of the capabilities of the Atacama Large Millimeter/submillimeter Array (ALMA) and of a Next Generation Very Large Array (ngVLA) to detect and resolve substructures due to terrestrial planets and Super-Earths in nearby planet-forming disks.

Nitrogen is a biosignature gas that cannot be maintained in its Earth-like ratio with CO2 under abiotic conditions. It has also proven to be notoriously hard to detect at optical and infrared wavelengths.

In the broadest sense, the primary goal of exoplanet demographic surveys is to determine the frequency and distribution of planets as a function of as many of the physical parameters that may influence planet formation and evolution as possible, over as broad of a range of these parameters as possible.

Today, we know ~4330 exoplanets orbiting their host stars in ~3200 planetary systems. The diversity of these exoplanets is large, and none of the known exoplanets is a twin to any of the solar system planets, nor is any of the known extrasolar planetary systems a twin of the solar system.

One of the most promising avenues for the detailed study of temperate Earth-sized exoplanets is the detection of such planets in transit in front of stars small and nearby enough to make possible their thorough atmospheric characterisation with next generation telescopes like the James Webb Space telescope (JWST) or Extremely Large Telescope (ELT).

We report the discovery of a Neptune-like planet (LP 714-47 b, P = 4.05204 d, m_b = 30.8 +/- 1.5 M_earth , R_b = 4.7 +/- 0.3 R_earth ) located in the 'hot Neptune desert'.