Astronomers used a method once theorized by Albert Einstein to find a mysterious and rare planet on the edge of our galaxy.
The planet, AT2021uey b, is a Jupiter-sized gas giant located about 3,200 light-years from Earth in the galactic bulge. It takes AT2021uey b 4,170 days to orbit its dwarf star, according to a study published in the journal Astronomy & Astrophysics.
According to Live Scence, AT2021uey b’s shadow was first spotted in 2021 in data taken by the European Space Agency’s Gaia telescope.
It took the astronomers multiple check-ins to confirm the details of the planet.
The astronomers discovered the planet using microlensing, a method used only three times previously, according to the study.
Microlensing, which is based on Einstein’s theory of relativity, relies on massive objects moving through the galaxy to warp the fabric of the universe, called space-time.
Dr. Marius Maskoliunas, astronomer at Vilnius University and co-author of the study, discussed in a statement posted in Phys.org just how much work goes into using this method.
“This kind of work requires a lot of expertise, patience and, frankly, a bit of luck. You have to wait for a long time for the source star and the lensing object to align and then check an enormous amount of data,” Maskoliunas said in the statement. “Ninety percent of observed stars pulsate for various other reasons, and only a minority of cases show the microlensing effect.”
According to the study, microlensing occurs when a massive celestial body briefly positions itself directly in front of an even more distant star.
As the planet settles in front of the star during its journey, the light begins to curve around the planet, magnifying the light of the star. According to the study, this temporary magnified light is what astronomers are searching for.
Maskoliunas gave an example of how to imagine how microlensing works.
“What fascinates me about this method is that it can detect those invisible bodies. Imagine a bird flying past you. You don’t see the bird itself and don’t know what color it is — only its shadow,” Maskoliunas said in the statement. “But from it, you can, with some level of probability, determine whether it was a sparrow or a swan and at what distance from us. It’s an incredibly intriguing process.”
According to Live Science, there have been nearly 6,000 planets discovered since 1992 using two other more common practices known as transmit photometry and radial velocity.
These more common practices will detect planets through host stars becoming dimmer due to said planets. They will also detect the wobble of the planets’ gravitational pulls that occur.
