Researchers Find New Planet Larger Than Jupiter Through Rare Einstein-Predicted Method

Researchers from Vilnius University’s Faculty of Physics, along with other scientists, have recently discovered a new exoplanet using a method based on Einstein’s theory of relativity.

Speaking to HuffPost UK, Edita Stonkutė, Associate Professor at Vilnius University, Europlanet Secretary, Institute of Theoretical Physics and Astronomy, said that the group identified a “Jupiter-mass planet around an M-dwarf star using a unique method called gravitational microlensing”.

They explained, “The discovered planet is only the third of its kind located outside the Galactic Bulge and discovered with this method.” 

The discovery of the planet, named AT2021uey (which lies approximately 3,200 light-years away from Earth), has formed the basis of a paper published in Astronomy & Astrophysics. 

What is gravitational microlensing?

Gravitational microlensing, first predicted by Albert Einstein in 1936, is an effect that “briefly brightens a distant source star when another object passes in front of it, like a natural magnifying glass,” the Europlanet Secretary revealed to us.

The light from the distant star becomes amplified, creating a “pulsation.”  Astronomers look for this momentary “pulsation” when analysing vast amounts of data. Because any planets orbiting the star will be visible when it’s “magnified,” they’ll be able to spot those if the rare event is behind the pulsation. 

“The discovery took patience, collaboration, and a bit of luck,” Professor Stonkutė told us.

Dr Marius Maskoliūnas, the head of the Lithuanian research team, agreed.

“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. 90% of observed stars pulsate for various other reasons, and only a minority of cases show the microlensing effect,” he said.

In this case, Prof Lukasz Wyrzykowski suggested analysing data from the European Space Agency’s ‘Gaia’ telescope, verifying it, and supplementing it with ground-based observations. Vilnius University’s Molėtai Astronomical Observatory hosts telescopes suitable for the task, though researchers say the discovery happened almost by chance.

“Most microlensing effects are recorded at the densest part of the galaxy – in its
centre and disk. However, we managed to find this microlensing phenomenon quite far from the centre, in the so-called galactic halo,” Professor Stonkutė shared. 

The team found a planet 1.3 times the size of Jupiter, which orbits around a so-called M dwarf – a relatively small and cool star – once every 4,170 days.

“This is only the third planet in observational history to be discovered so far from the Galactic bulge,” Stonkutė said.

It’s a promising sign for the future of space exploration

Researchers described AT2021uey as a “unique example” of how gravitational lensing can be applied in space exploration, because it is an atypical discovery.

“It also shows how much of the universe is still hidden,” Professor Stonkutė told HuffPost UK. 

“Microlensing helps scientists detect planets and objects that are otherwise invisible, opening new paths for space exploration.”