Astronomers discover scaled-down Jupiter and Saturn in a faraway solar system like our own

Previously, astronomers had found four planets using microlensing; two of those were found by the Ohio State University-based MicroFUN group. The latest two planets make six, and he expects that number to double over the next year as other teams publish new findings.

"We're just getting better at what we do," Gaudi said. "We've hit our stride with this technique."

He has also calculated that the next generation of microlensing experiments -- using telescopes on the ground and in space -- will likely be able to detect analogs to all of our solar system’s planets, except for the tiniest one, Mercury.

The current discovery relied on 11 different ground-based telescopes in countries around the world, including New Zealand, Tasmania, Israel, Chile, the Canary Islands, and the United States.

Both professional and amateur skywatchers joined in. People from three other microlensing collaborations -- the Microlensing Observations in Astrophysics (MOA) Collaboration, the Probing Lensing Anomalies NETwork (PLANET), and the RoboNet Collaboration -- all contributed observations and are co-authors of the study with MicroFUN and OGLE.

Gaudi described this microlensing event as the most complicated one ever studied. The astronomers carefully modeled their data on computers, and explored all possible explanations for the light signal. A year and a half later, they were confident that they’d found two planets. In part, their confidence came from additional observations from the W.M. Keck Observatory in Hawaii, which they used to calculate the mass of the star.

Ohio State coauthors on the Science paper included Darren DePoy and Richard Pogge, both professors of astronomy; and Subo Dong and Stephan Frank, both graduate students.

Other coauthors hailed from the University of Notre Dame, Warsaw University Observatory, Auckland Observatory, Tel-Aviv University, Farm Cove Observatory, Mt. John Observatory, Lawrence Livermore National Laboratory, Princeton University Observatory, Universidad de Concepción, University of Cambridge, Chungbuk National University, Korea Astronomy and Space Science Institute, Campo Catino Astronomical Observatory, Nagoya University, Massey University, University of Auckland, University of Canterbury, Victoria University, Konan University, Nagano National College of Technology, University of Manchester, Tokyo Metropolitan College of Aeronautics, University of Exeter, Université Pierre et Marie Curie, Liverpool John Moores University, University of St. Andrews, University of Tasmania, Université Paul Sabatier-Toulouse, Dartmouth College, and the University of Oxford.

This work was sponsored by the National Science Foundation; NASA; the Polish Ministry of Scientific Research and Information Technology; the SRC Korea Science & Engineering Foundation; the Korea Astronomy & Space Science Institute; Deutsche Forschungsgemeinschaft; the Particle Physics and Astronomy Research Council; The European Union’s Framework Programme for Research and Technological Development; The Israel Science Foundation; the Marsden Fund of New Zealand; the Japan Ministry of Education, Culture, Sports, Science and Technology; and the Japan Society for the Promotion of Science.