NASA's TESS spacecraft discovers a weird system of exoplanets unlike anything seen before

Using NASA's exoplanet-hunting spacecraft TESS (Transiting Exoplanet Survey Satellite) and Antarctic Search for Transiting ExoPlanets (ASTEP) on the Antarctic Plateau, astronomers have discovered a rare and uniquely weird planetary system. The extrasolar planets, or exoplanets , that swirl around the star TOI-201 have orbits that are changing so rapidly that astronomers can see the changes in real time. The behavior of the system, located around 370 light-years from Earth, is something scientists have never seen before. TOI-201 is 1.3 times the mass of the sun and also has a diameter of 1.3 times the size of our home star. The exoplanets that orbit the star include a rocky super-Earth with six times the mass of our planet that has a year lasting just 5.8 Earth-days. Its planetary siblings are a gas giant with half the mass of Jupiter , completing an orbit every 53 days, designated TOI-201b, and another gas giant that has 16 times the mass of Jupiter that completes an orbit every 2,883 days (about 7.9 years). "Most planetary systems appear as 'peas in a pod,' meaning the planets have a similar range of parameters and share a similar orbital plane," team member Amaury Triaud, from the University of Birmingham in the U.K., said in a statement. "This is not the case in the TOI-201 system, which contains three orbiting objects very distinct from one another, and which interact gravitationally." The team's results were published on April 15 in the journal Science. …