Scientists Capture Rare Direct Image of Planet 400 Light Years Away

Scientists have captured a photograph of a planet located more than 400 light years away from the Earth.

The finding is rare and adds to only a handful of planets that have been observed directly with telescopes.

The planet is also one of the youngest ever discovered around a distant infant star and could help researchers find out more about how planets form over time, according to the University of Hawai'i.

Exoplanet hunting is a branch of astronomy in which scientists peer deep into the cosmos to find hints of other planetary systems like ours. By doing this, they can help piece together how our own world was formed.

Because stars are so far away and their planets are so tiny and dim in comparison, it's usually impossible with current methods to actually see a distant world. Instead, scientists have to rely on indirect observations, detecting planets without actually seeing them.

Scientists can do this by looking at a distant star for a long time. If the star regularly appears to dim for a short while, this suggests a planet is orbiting it, and we can infer some details about what that planet might be like. This is called the transit method.

Another way we can indirectly spot distant worlds is by looking at how a star ever-so slightly wobbles or is pulled by the gravity of its orbiting planets. Again, we don't actually see the planets this way, but we can tell they are there.

Thousands of planets have been discovered in this way. Actually seeing a distant planet is much more difficult because their stars are just too bright. In NASA's words: "It's like trying to see a firefly flitting around a spotlight."

Now, scientists have found an exoplanet, called 2M0437b, located around 128 parsecs (417 light years) away from Earth, which they detected directly. Not only that, but it's newly formed at just a few million years old.

2M0437b is very far away from its host star at a distance of 118 astronomical units—Earth is one astronomical unit from the sun. It is also massive—so much so that it falls into a category of planets known as "super-Jupiters."

A Rare Combination

Because it's young, it has a high temperature of around 1,400 to 1,500 K (1,127 to 1,227 degrees Celsius). And because it's both hot and far away from its star—a rare combination—scientists can see it directly.

"This serendipitous discovery adds to an elite list of planets that we can directly observe with our telescopes," said Eric Gaidos, lead author of the study and a professor at the University of Hawai'i at Mānoa, in a university press release that also includes the direct image of the planet.

"By analyzing the light from this planet we can say something about its composition, and perhaps where and how it formed in a long-vanished disk of gas and dust around its host star."

Gaidos added that future studies with telescopes like the upcoming James Webb Space Telescope could reveal more about 2M0437b's atmosphere.

2M0437b was first spotted using the Subaru Telescope on Hawaii's Maunakea mountain, and further observations were carried out using the Keck Observatory in the same region.

The study outlining its discovery, A Directly-Imaged Planetary-Mass Companion to a Young Taurus M Dwarf Star, was published as a preprint on October 19 on the ArXiv repository and has been accepted for publication in the journal Monthly Notices of the Royal Astronomical Society.

A file photo of an exoplanet passing in front of its host star. Most exoplanets are observed indirectly. dzika_mrowka/Getty