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LCO Data Confirm the Discovery of an Earth-Size Exoplanet

May 17, 2023

LP 791-18 d, illustrated here, is an Earth-size world about 90 light-years away. Credit: NASA’s Goddard Space Flight Center/Chris Smith (KRBwyle)

A paper published today in the scientific journal Nature describes the discovery of a world beyond our solar system, the Earth-size exoplanet LP 791-18d.

The group that discovered the planet is led by Merrin Peterson, a graduate student at the Trottier Institute for Research on Exoplanets (iREx) based at the University of Montreal. NASA and the Smithsonian Institution announced the discovery in press releases today.

The researchers found and studied the planet using data from NASA’s Transiting Exoplanet Survey Satellite (TESS) and Spitzer Space Telescope, as well as a suite of ground-based observatories, including the Las Cumbres Observatory network of 1-meter telescopes.

The new planet is the 3rd discovered in this system. The transit signal for this planet was first noticed in a Spitzer observation that was triggered after transit of two planets were detected in the TESS data. LCO follow up observations were critical in the effort to first help determine the period of the new planet and later were used to calculate the transit timing variations (TTVs). In total, there were 24 LCO 1-meter transit observations collected in support of the discovery and measurement of the TTVs. The determination of the orbital period for this exoplanet, derived from the Spitzer transit and the initial LCO observations, allowed the research team to embark on further studies to characterize the orbit of LP791-18d.

Las Cumbres Observatory provides critical follow-up data to time-sensitive astronomical discoveries.

Dr. Lisa Storrie-Lombardi, the Director of LCO, said that “Las Cumbres Observatory is very happy to be able to contribute to another exciting result from NASA missions.”