NASA's Spitzer Space Telescope teamed up with a telescope on Earth to discover one of the most distant planets known to science.
The gas planet is located a staggering 13,000 light-years away the Harvard-Smithsonian Center for Astrophysics reported. The findings show Spitzer could map out how planets are distributed throughout the Milky Way.
"We don't know if planets are more common in our galaxy's central bulge or the disk of the galaxy, which is why these observations are so important," said Jennifer Yee of the Harvard-Smithsonian Center for Astrophysics (CfA), and a NASA Sagan fellow.
The other telescope used in the study was OGLE's Warsaw Telescope at the Las Campanas Observatory in Chile. It scans the skies for a phenomenon called microlensing, which occurs when one star passes in front of another, creating a magnifying "lens." If a planet is orbiting that star, it can cause a "blip" in the lensing effect, allowing scientists to learn of their existence. This technique has already facilitated the discovery of about 30 new planets, the most distant of which resides 25,000 light-years away.
"Microlensing experiments are already detecting planets from the solar neighborhood to almost the center of the Milky Way," said co-author Andrew Gould of The Ohio State University, Columbus. "And so they can, in principle, tell us the relative efficiency of planet formation across this huge expanse of our galaxy."
The microlensing technique can pinpoint the presence of planets, but cannot determine their exact location. To remedy this, Spitzer can provide missing information and give scientists a better idea of the planets' place in space. The technique of two telescopes looking at an object from different vantage points is referred to as parallax.
"Spitzer is the first space telescope to make a microlens parallax measurement for a planet," Yee said. "Traditional parallax techniques that employ ground-based telescopes are not as effective at such great distances."
Spitzer is scheduled to look at about 120 microlensing events this summer.
"We've mainly explored our own solar neighborhood so far," said Sebastiano Calchi Novati, a Visiting Sagan Fellow at NASA's Exoplanet Science Institute at the California Institute of Technology, Pasadena. "Now we can use these single lenses to do statistics on planets as a whole and learn about their distribution in the galaxy."
The findings were published in the Astrophysical Journal.
