Looking for gigantic planets?
You came to the right place!
The search for a new stellar body is never-ending.
Space is full of astronomical bodies, and astronomers are constantly on the lookout
for new stars and planets in humanity’s known universe.
In one such effort, an astronomer from the University of California, Riverside (UCR),
collaborated with a group of eagle-eyed citizen scientists and discovered a giant gas planet
hidden from observation by typical stargazing tools.
The new planet, TOI-2180 b, is an exoplanet that orbits a yellow dwarf or a G-type star.
It is roughly three times the mass of Jupiter but has the same diameter.
Researchers believe that it might contain 105 times the mass of Earth with respect to
substances, which are heavier than helium and hydrogen.
It is quite a rare phenomenon because nothing like this has ever existed before in our solar
system, and astronomers are pretty excited about it.
Paul Dalba from the University of California, Riverside, assisted in the confirmation of
the planet’s existence, commented that TOI-2180 b is a fascinating planet to have discovered.
It has the trifecta of, one, a several-hundred-day orbit; two, the distance between TOI-2180
b and Earth is 379 light-years which is considered close for an exoplanet; and three, we can
see it transit in front of its star.
It is quite rare for astronomers to find a planet that ticks all three of these boxes.
Dalba also mentioned that the planet is unique in that it takes 261 days to orbit its star,
which is quite a long time compared to many other known gas giants beyond our solar system,
which take 18 hours.
Astronomers can learn more about the planet because of its relative proximity to Earth
and the brightness of the star it orbits.
In order to find exoplanets that orbit stars other than our sun, NASA’s TESS satellite
(Transiting Exoplanet Survey Satellite) looks at one section of the sky for a month, then
moves on.
It looks for brightness dips that happen when a planet passes in front of a star.
Dalba stated that the rule of thumb is that we need to see three dips or transits before
we believe we have found a planet.
Telescope jitters and stellar activity masquerading as a planet could cause a single transit event.
For such reasons, TESS is not focused on these single transit events.
Nevertheless, a small group of citizen scientists is.
Tom Jacobs, a group member, and retired U.S. naval officer, observed dim light from the
planet’s star just once while looking through TESS data.
His group informed Dalba, who has specialized in studying planets that take a long time
to orbit their stars.
To observe the planet’s gravitational tug on the star, Dalba and his colleagues used
Lick Observatory’s Automated Planet Finder Telescope, also known as Rocky Planet Finder.
This allowed them to compute the mass of TOI-2180 b and estimate a range of possibilities for
its orbit.
Dalba coordinated a campaign using 14 different telescopes across three continents in the
northern hemisphere in the hopes of observing a second transit event.
The campaign yielded 20,000 images of the TOI-2180 b for 11 days in August 2021, though
none of them reliably discovered the planet.
However, the campaign did lead the group to estimate that TESS will observe the planet
transit its star for the third time in February when they are planning to conduct a follow-up
study.
The National Science Foundation’s Astronomy and Astrophysics Postdoctoral Fellowship Program
provided funding for Dalba’s research.
The citizen planet hunters’ organization uses publicly available data from NASA spacecraft
such as TESS and searches for single transit occurrences.
While professional astronomers use algorithms to automatically scan large amounts of data,
the Visual Survey Group uses a program they designed to inspect telescope data by eye.
The effort they put in is highly significant and noteworthy because it’s difficult to
come up with codes that can consistently identify single transit events.
This is one area where humans continue to outperform code.
Finding more stellar bodies like TOI-2180 b results from a combined effort between professional
astronomers and citizen scientists.
When TESS tracks the planet next month, the team expects to find even more data.