Have astronomers found first moon outside our solar system?
47 views · Published 9 October 2018 · 3:26 · Indexed 22 September 2026
Channel: AP Archive · 2018 · News & Politics
(4 Oct 2018) LEADIN: Plenty of planets exist beyond our solar system, but a moon around those worlds is yet to be confirmed, until, possibly, now. Astronomers may have found the first moon outside our solar system. Two Columbia University researchers presented the tantalizing evidence Wednesday (3 October). STORYLINE: Two astronomers have found what may be the first moon orbiting a planet outside our solar system. Called an exomoon, it's a moon that goes around a planet, called an exoplanet, outside our solar system. Their findings appear in this week's Science Advances. Columbia University researchers Alex Teachey and David Kipping said more evidence is needed to confirm the exomoon. A clearer picture may be available as early as next year. "What we want to know is whether these moons are common, maybe even they are places where we might find life around them," says Kipping. "And, perhaps they will teach us about how planets and satellites form elsewhere in the universe." The planet in question is about 8,000 light-years away and orbits a star about the size of our own sun, but older. The planet that orbits the star is called Kepler 1625b and is about the size of Jupiter. The potential exomoon is about the size of Neptune. If indeed a moon, it would be about 2 million miles (3 million kilometers) from its planet and appear twice as big in its sky, as the moon does in ours. This planet was the only one of nearly 300 exoplanets surveyed by the team for possible alien moons that offered real potential. "The way we look for planets is to try and see the shadow of the planet, essentially," explains Kipping. "We can't see the planet separate from the star, because they're just too far away. So instead, we see the planet pass in front of the star, blocks out some of the light for a small amount of time and we can tell there is a planet there." Initially, the researchers used NASA'S Kepler Space Telescope to identify the potential moon. They then turned to the Hubble Space Telescope and observed what they believed to be the potential moon's fourth transit last October. "We knew there wasn't enough data with Kepler, unless we asked Hubble, which is a much more powerful telescope," says Kipping. "We get actually four-times more precise data using Hubble than we do with Kepler and that gives you a resolution power to see these tiny signatures that Kepler missed." The researchers are putting their work out there now, rather than waiting, so that others in the scientific community can chime in. They say the jury is still out on whether this is really the first moon detected outside our solar system. They hope to get some more time with Hubble to confirm it. "What we see in our data is a very clear moonlike dip and it is unprecedented compared to all our previous data," says Kipping. "So, what we really like to see is a second example of it. The only way we're going to do that is if we get more data. "So, we are asking Hubble if we can re-observe the star in the future and hopefully get that second event and really make it a clear-cut case that this is (a) real exomoon." Whether confirmed or not, the subject offers insight into how rare - or how common - our own solar system might be. Moons are abundant in our own solar system, with close to 200. Of the eight planets in our solar system, only Mercury and Venus have none. Right now, neither astronomer is addressing the possibility of habitability of this exomoon. The planet is gaseous, not rocky like Earth and the moon, if confirmed, will also be gaseous. Find out more about AP Archive: http://www.aparchive.com/HowWeWork Twitter: https://twitter.com/AP_Archive Facebook: https://www.facebook.com/APArchives Instagram: https://www.instagram.com/APNews/ You can license this story through AP Archive: http://www.aparchive.com/metadata/youtube/d9515019b82547777ea914c1126ccc71
