A newly discovered planet in a young star system located 100 light-years away could give astronomers an idea what Jupiter looked like early in its development.
The planet, 51 Eridani b, is relatively young -- only 20 million years old. That might sound ancient to most people, but, as the researchers behind the discovery noted, it formed "40 million years after the dinosaurs died out."
It's the first planet to be discovered by the Gemini Planet Imager, located in the 26-foot Gemini South Telescope in Chile, which uses a novel method to discover exoplanets.
Instead of looking for stars that dim as planets pass between them and Earth, like the Kepler space observatory does, it searches for light generated directly by the planet.
"To detect planets, Kepler sees their shadow," Bruce Macintosh, a professor of physics at Stanford University, said in a statement. "The Gemini Planet Imager instead sees their glow, which we refer to as direct imaging."
His research is published in the current issue of the journal Science.
Dubbed "young Jupiter" by researchers, 51 Eridani b showed the strongest methane signature ever detected on an exoplanet, making it much like the gas giants in our own solar system. It's also large -- about twice the mass of Jupiter -- and relatively cool at 800 degrees Fahrenheit. (Planets as young as 51 Eridani b are often as hot as 1,200 degrees Fahrenheit).
All of those factors make for an exoplanet very similar to Jupiter, which could provide clues about how our own solar system and its gas giants formed nearly 5 billion years ago.