NASA's TESS spots earth sized planet

New Delhi : NASA's latest planet-hunting probe has discovered an Earth size exoplanet orbiting a star 53 light-years away.

The Transiting Exoplanets Survey Satellite (TESS) also spotted a Neptune size planet in the same system.

The latest discoveries have been published in the Astrophysical Journal Letters.

"It’s so exciting that TESS, which launched just about a year ago, is already a game-changer in the planet-hunting business," said Johanna Teske, Carnegie Institution for Science in the US.

"The spacecraft surveys the sky and we collaborate with the TESS follow-up community to flag potentially interesting targets for additional observations using ground-based telescopes and instruments," Teske said in a statement.

During the research the Planet Finder Spectrograph (PFS) on the Magellan II telescope in Chile, played the role of a crucial component. With its help, the planetary nature of the TESS signal was measured.

The PFS works using a technique called the radial velocity method, which is currently the only way for astronomers to measure the masses of individual planets. 

 “PFS is one of the only instruments in the Southern Hemisphere that can do these types of measurements. So, it will be a very important part of further characterising the planets found by the TESS mission,” Teske said.

With an orbit that takes about 36 days to complete, the sub-Neptune, HD 21749b, has the longest period of any of the TESS discoveries published so far, researchers said.