Discovery Alert: Earth-sized Planet Has a ‘Lava Hemisphere’

Details: A team of astronomers analyzed this system using data from NASA’s TESS (Transiting Exoplanet Survey Satellite), which spots “transits,” or instances where planets cross in front of their star as they orbit, blocking a tiny piece of the starlight. Two planets had already been previously discovered in this planetary system, so to see what else might be lurking in the star’s orbit, the team took the data and removed the signals of the two known planets. This allowed them to see an additional signal – a small transit that would reappear every 4.2 days. Upon further investigation, they were able to validate that this was actually a third, smaller planet.