Skip to main content

Previously unknown exoplanet discovered using machine learning

When it comes to discovering new astronomical bodies, sometimes humans are irreplaceable thanks to their skills in pattern detection. But in other cases, computers can spot things that aren’t visible to humans — including a recent instance where an exoplanet was discovered using machine learning.

The exoplanet was discovered by University of Georgia researchers within a protoplanetary disk called HD 142666. A protoplanetary disk is a rotating disk of gas that swirls around young stars, and from which planets are formed. Planets are formed within these disks as matter clumps together until it eventually has enough gravity to pull more material in. The researchers looked at a previous set of observations of a whole set of protoplanetary disks, and used a machine learning model to search for exoplanets that might have been missed the first time around. They identified one disk where a planet was likely to be, based on the unusual way that gas moved around within the disk.

Disk Substructures at High Angular Resolution Project (DSHARP)

“We confirmed the planet using traditional techniques, but our models directed us to run those simulations and showed us exactly where the planet might be,” said lead author Jason Terry in a statement. “When we applied our models to a set of older observations, they identified a disk that wasn’t known to have a planet despite having already been analyzed. Like previous discoveries, we ran simulations of the disk and found that a planet could recreate the observation.”

The researchers say that this is a proof of concept showing that machine learning can be used to make new discoveries of exoplanets, even with data that has previously been analyzed. That could mean more exoplanet discoveries in the future, as well as discoveries being made faster.

“This demonstrates that our models — and machine learning in general — have the ability to quickly and accurately identify important information that people can miss. This has the potential to dramatically speed up analysis and subsequent theoretical insights,” Terry said. “It only took about an hour to analyze that entire catalog and find strong evidence for a new planet in a specific spot, so we think there will be an important place for these types of techniques as our data sets get even larger.”

The research is published in The Astrophysical Journal.

Editors' Recommendations

Georgina Torbet
Georgina is the Digital Trends space writer, covering human space exploration, planetary science, and cosmology. She…
Hubble spots an Earth-sized exoplanet just 22 light-years away
An artist’s concept of the nearby exoplanet, LTT 1445Ac, which is the size of Earth. The planet orbits a red dwarf star.

Although astronomers have now discovered more than 5,000 exoplanets, or planets outside of the solar system, the large majority of these planets are considerably larger than Earth. That's partly because it's easier to spot larger planets from tremendous distances across space. So it's exciting when an Earth-sized planet is discovered -- and the Hubble Space Telescope has recently confirmed that a nearby planet, which is diminutive by exoplanet standards, is 1.07 times the size of Earth.

The planet LTT 1445Ac was first discovered by NASA's Transiting Exoplanet Survey Satellite (TESS) in 2022, but it was hard to determine its exact size due to the plane of its orbit around its star as seen from Earth. “There was a chance that this system has an unlucky geometry and if that’s the case, we wouldn’t measure the right size. But with Hubble’s capabilities we nailed its diameter,” said lead researcher Emily Pass of the Harvard-Smithsonian Center for Astrophysics in a statement.

Read more
James Webb sees evidence of an ocean-covered ‘Hycean’ exoplanet
This illustration shows what exoplanet K2-18 b could look like based on science data. K2-18 b, an exoplanet 8.6 times as massive as Earth, orbits the cool dwarf star K2-18 in the habitable zone and lies 120 light years from Earth.

The James Webb Space Telescope has once again peered into the atmosphere of an exoplanet, and this time it has identified indications that the planet could be covered in oceans. The planet K2-18 b is just 120 light-years away from Earth in the constellation of Leo and is a type of planet called a sub-Neptune which is unlike any planet in our solar system.

Researchers used Webb to investigate K2-18 b, which is more than eight times the mass of Earth and orbits a small, cool dwarf star. It is located within the habitable zone of the star, where it is possible for water to exist on the planet's surface, and the data suggests that this could be an ocean world.

Read more
Watch a video of an exoplanet orbiting its star — made from 17 years of observations
Artist’s impression of the planet Beta Pictoris b orbiting its star.

It's rare that we get to see exoplanets themselves. Most often, planets in other star systems are too small and too dim to be directly detected, so astronomers infer their presence based on their effects on their host stars. But occasionally, it is possible to image a star directly -- and recently, astronomers managed to create not only an image, but a video of an exoplanet orbiting its star.

17 years of real footage of an exoplanet (Beta Pic b)

Read more