First Evidence Of a Possible 'Exomoon' Found
Astronomers have reportedly found the first signs of what might be an 'exomoon' - a moon orbiting a planet that lies outside the solar system - in the far world.
At present around 850 extrasolar planets-planets outside the solar system are known and among them most are sterile gas giants, similar to Jupiter.
The study has been led by the joint Japan-New Zealand-American Microlensing Observations in Astrophysics (MOA) and the Probing Lensing Anomalies NETwork (PLANET) programs, using telescopes installed in New Zealand and Tasmania.
In their experiment, astronomers used a technique called gravitational microlensing in which one star passes in front of another as seen from Earth. The closer one can act like a magnifying glass to focus and brighten the light of the more distant star for a period of days to weeks during the event.
Researchers said though it was impossible to confirm the presence of 'exomoon', it was tantalizing first step toward locating others. The discovery was possible by watching a chance encounter of objects in our galaxy which can be witnessed only once.
"We won't have a chance to observe the exomoon candidate again," said David Bennett of the University of Notre Dame, Ind., lead author of a new paper in the press release. "But we can expect more unexpected finds like this."
Researchers however warned that in some cases, the nature of the foreground, lensing object is not clear.
"One possibility is for the lensing system to be a planet and its moon, which if true, would be a spectacular discovery of a totally new type of system," said Wes Traub, the chief scientist for NASA's Exoplanet Exploration Program office at NASA's Jet Propulsion Laboratory, Pasadena, Calif., who was not involved in the study, according to RedOrbit. "The researchers' models point to the moon solution, but if you simply look at what scenario is more likely in nature, the star solution wins."
The findings of the study is appearing in the Astrophysical Journal.