A Recap of Some Exoplanet News

Here is a recap of some Exoplanets news that came to my attention last week – four science stories and one music video.

Orbits of all three known planets in the TOI 700 system. 
Image credit: NASA’s Goddard Space Flight Center/Chris Smith (USRA)

First, NASA announced that Tess, the Transiting Exoplanet Survey Satellite, has discovered its first Earth-size planet in its star’s habitable zone. TOI 700 d orbits a red dwarf star that is relatively quiet – no flares were detected in 11 months of TESS data. The star is located just over 100 light-years away in the southern constellation Dorado. It has about 40% of the Sun’s mass and size and about half its surface temperature. Three planets have been detected but only the outermost is in the habitable zone where water can remain liquid on its surface.

Anna Hughes, a PhD candidate at UBC, spoke at the January RASC Vancouver monthly meeting about Magnetic Fields Around Dwarf Stars. Some types of magnetic fields are associated with active stars that can throw bursts of radiation and charged particles at orbiting planets, potentially sterilizing them. She explained her work in studying magnetic fields around ultra-cool dwarf stars and their impact on the potential habitability of surrounding exoplanets. Ultra-cool dwarfs were not expected to have magnetic fields because they are completely convective, without the shearing between different layers that generates magnetic fields in larger stars. Using large arrays of radio telescopes, Hughes studied several ultra-cool dwarf stars where the presence of magnetic fields has recently been detected. One of the system she studied was Trappist-1, a system with seven confirmed exoplanets, three of which are in the habitable zone.

Cool fact: ultra-cool dwarf stars have not yet experienced death. Their lifetimes are expected to exceed several hundred billion years which is longer than age of the universe.

A high-school student discovered a new exoplanet three days after starting his internship at NASA. NASA confirmed the work of Wolf Cukier, that was submitting in a paper announcing the discovery of TOI 1338 b at the 235th American Astronomical Society meeting. It is a binary system and Cukier saw a signal that that was first thought to be a stellar eclipse. Instead, it turned out to be a planet orbiting two stars.

Artash Nath, a Grade 8 Student from Toronto, posted a message to the RASC mail list about his project with a free module using Python and a Jupyter Notebook that allows anyone to get started with machine learning on a dataset of transit light curves to predict the exoplanet planet-star radius ratio. An online tutorial is available from his Github account www.github.com/Artash-N.

On a lighter note, a older video on exoplanets created by Montrealer, Tim Blais from A Capella Science, got my attention by fitting “Pegasi 51-b” and “Spectral Class G” into the rhyme and rhythm of his “Whole New Worlds” video.