Riverside: A group of astronomers and eagle-eyed citizen scientists at the University of California, Riverside have discovered a giant gas giant hidden out of sight by a typical starry sky observation tool.
Planet TOI-2180b has the same diameter as Jupiter, but has almost three times the mass. Researchers also believed that elements heavier than helium and hydrogen contained 105 times the mass of the Earth.
Details of the findings were published in the Astronomical Journal and presented at the American Astronomical Society Virtual Press Event on January 13.
“TOI-2180b is an exciting planet to discover,” said UCR astronomer Paul Dalba, who helped confirm the existence of the planet. “It can be seen 1) having an orbit of hundreds of days, 2) relatively close to Earth (which is considered close to 379 light-years on exoplanets), and 3) passing in front of stars. It is very rare for an astronomer to discover a planet that checks all three boxes. “
Dalba also explained that the planet is special because it took 261 days to complete the journey around the star compared to many known gas giants outside our solar system. The relative proximity to the Earth and the brightness of the stars it orbits may also allow astronomers to learn more about the Earth.
To find extrasolar planets orbiting stars other than our Sun, NASA’s TESS satellites look part of the sky for a month before proceeding. Search for the diminished brightness that occurs when a planet crosses in front of a star.
“The rule of thumb is that you need to check three” dips “or transits before you believe you’ve found a planet,” Dalba said. A single transit event can be triggered by a jittery telescope, or a star disguised as a planet. For these reasons, TESS is not focused on these single transit events. However, this is the case with a small group of citizen scientists.
Looking at the TESS data, group member and former US Navy officer Tom Jacobs saw the light from the TOI-2180 star dimmed only once. His group warned Dalba, who specializes in the study of planets that take a long time to orbit the stars.
Using the Lick Observatory’s automated planet finder, Dalba and his colleagues observed the gravitational pull of the planet against the stars. This allowed us to calculate the mass of TOI-2180 b and estimate its orbital potential range.
Expecting to observe the second transit event, Dalba organized a campaign using 14 different telescopes on three continents of the Northern Hemisphere. In the 11 days of August 2021, this effort resulted in 20,000 images of the TOI-2180 star, none of which could confidently detect the planet.
However, the campaign led the group to estimate that when they planned a follow-up, TESS would see the planet pass through the star again in February.
The Citizen Planet Hunters Group retrieves publicly available data from NASA satellites such as TESS and looks for a single transit event. While professional astronomers used algorithms to automatically scan large amounts of data, the Visual Survey Group used a program they created to visually inspect telescope data.
“Their efforts are very important and impressive, as it is difficult to write code that can reliably identify a single transit event,” says Dalba. “This is one of the areas where humans are still beating the code.”
https://www.siasat.com/research-finds-gigantic-planet-hidden-in-plain-sight-2259899/ Research has shown that giant planets are hidden in clear visibility.