Using a technique called microlensing, astrophysics researchers from the University of Oklahoma were able to detect a “population” of planets beyond our Milky Way galaxy.
Xinyu Dai, professor in the Homer L. Dodge Department of Physics and Astronomy, OU College of Arts and Sciences, with OU postdoctoral researcher Eduardo Guerras, made the discovery with data from the National Aeronautics and Space Administration's Chandra X-ray Observatory, a telescope in space that is controlled by the Smithsonian Astrophysical Observatory.
"We are very excited about this discovery. This is the first time anyone has discovered planets outside our galaxy," said Dai. "These small planets are the best candidate for the signature we observed in this study using the microlensing technique. We analyzed the high frequency of the signature by modeling the data to determine the mass."
According to the researchers they were able to detect as many as 2,000 planets reaching as far as 3.8 billion light years away.
A technique called microlensing, which is what the researchers used in this particular effort, uses background light which is bending around an object to study the what lies in between. This time, the bright beams of a quasar helped researchers to detect the presence of large bodies in a galaxy that lies between Earth and the light source.
“We show that quasar microlensing provides a means to probe extragalactic planets in the lens galaxy, by studying the microlensing properties of emission close to the event horizon of the supermassive black hole of the background quasar, using the current generation telescopes,” the researchers write. The team then applied a formula to the data they gathered and determined that the only explanation for the particular energy signatures they were seeing was the presence of thousands of planets.
Getting a read on these planets separately is still a ways off at this point; but it is just breathtaking what is potentially possible today that could not have even been imagined a couple of decades ago.