At first, the researchers saw the dip in light caused by the planet passing across the face of the star, but not long afterward, they saw a second, smaller dip, likely caused by the moon transiting across the star.
In a paper published Wednesday in Science Advances magazine, researchers at Columbia University outline evidence supporting the existence of a moon orbiting the exoplanet Kepler-1625b, using data from the United States space agency NASA's Hubble Space Telescope.
The discovery, detailed by researchers yesterday, was a surprise, and not because it showed that moons exist elsewhere ― they felt it was only a matter of time for one to be found in another star system. "If confirmed by follow-up Hubble observations, the finding could provide vital clues about the development of planetary systems and may cause experts to revisit theories of how moons form around planets".
Only two planets in our solar system - Mercury and Venus - don't have moons, Kipping said. Astronomers think numerous gas giants' moons are captured asteroids.
It orbits its parent star at a distance similar to the distance between the Sun and Earth, which puts it - and its candidate moon - at the inner edge of the habitable zone of the star system.
With the Hubble, they monitored the exoplanet Kepler-1625b as it passed between the star it orbits - Kepler-1625 - and Earth, and they looked at how the brightness of that star dimmed as the planet passed in front of it.
The first exomoon may be a Neptune-size world that orbits a Jupiter-size planet.
Kipping and Teachey relied on the "transit" method already used by researchers to discover almost 4,000 planets outside our solar system, called exoplanets.
I Know You’re Not Thinking, You Never Do
Do you have a question on trade? "I'm not a drinker, I can honestly say I've never had a beer in my life", Trump said. While Vega was reaching for her microphone, Trump took a few shots at her.
Despite the exomoon's huge size, proving its existence has been hard. In some configurations, that tug will be in the direction of the planet's orbit around its star, causing the transit to occur sooner than expected.
The Kepler and Hubble observations, along with modeling work, suggest that the moon is about the size of Neptune and 1.5 percent as massive as Kepler-1625b. The Kepler outcomes were sufficient enough for the group to achieve 40 hours of time with Hubble to vehemently study the planet acquiring the data four times more accurate than that of Kepler.
So far, our own solar system appears atypical in many respects, but planet-hunting remains in its infancy. It was like "a moon trailing the planet like a dog following its owner on a leash", Kipping said.
Barely noticeable dips in the Kepler light curves, just to either side of the main lightcurve dip produced by the planet, pointed to the possibility a second body making transit alongside the gas giant, and since the location of the secondary dip changed with each transit of the planet, it indicated that the second body could be orbiting around the planet.
"It was definitely a shocking moment to see that Hubble light curve, my heart started beating a little faster as I kept looking at that signature". This could explain why the moon is 3 million kilometers from its planet; they were probably closer in the past. But because both bodies are gaseous (which means neither are habitable as we understand it, in case you were wondering), and because of the moon's size, that raises questions about how it got there. "We think that they're at the right temperature to have liquid water on the surface, but of course there is no real surface because they are gas giant planets". Saturn's moons were formed from its rings. All the planets in our solar system except Mercury and Venus have moons. A giant moon like Neptune points to other mechanisms. If they are able to observe a full transit, representative of a "clean moonlike event, then I think we're done", Kipping said.
They followed up with the Hubble Space Telescope.
Until now, no exomoons have been confirmed. NASA's upcoming James Webb Space Telescope could really "clean-up" in the satellite search, Kipping said.
"If this does pan out and turn into a true discovery, it would be really revolutionary, but I don't think we're quite there yet", says Megan Bedell, an astronomer at the Flatiron Institute in NY.
- Goodale 'very concerned' by Russian spies' cyberattack on Canada, allies
- Trump taxes: NY authorities examine president's tax affairs
- Mourinho: Blame for United’s poor start to season not just on me
- Valencia look to extend Manchester United's poor run
- Donald Trump Jr Worried for Sons Amid Kavanaugh Accusations
- Amazon announces $50 4K-capable Fire TV Stick
- Key passages from Julie Swetnick's declaration alleging sexual misconduct against Brett Kavanaugh
- Kavanaugh's fellow Yalies transfixed by Senate hearing
- USA politics plumbs new depths as President Trump mocks women
- Bill Cosby spends first night in state prison