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Microlensing strikes again. Astronomers have been using the technique to detect everything from rogue planets to the most distant star ever seen. Now, astronomers have officially found another elusive object that has long been theorized, and that Universe Today first reported on back in 2009 but has never directly detected – a rogue black hole. That detection comes at the end of a 6-year observational campaign, with dozens of authors collaborating on a paper recently published in arXiv (meaning it has not yet been peer-reviewed). Those six years of painstakingly gathered data all started back in 2011, when a star...

In an incredible world first, astrophysicists have detected multiple planets in another galaxy, ranging from masses as small as the Moon to ones as great as Jupiter. Given how difficult it is to find exoplanets even within our Milky Way galaxy, this is no mean feat. Researchers at the University of Oklahoma achieved this thanks to clever use of gravitational microlensing. The technique, first predicted by Einstein's theory of general relativity, has been used to find exoplanets within Milky Way, and it's the only known way of finding the smallest and most distant planets, thousands of light-years from Earth. As...

Planetary Discovery around Ultracool Starby Paul Gilster on April 28, 2017 I have a special enthusiasm for microlensing as a means of exoplanet discovery. With microlensing, you never know what you’re going to come up with. Transits are easier to detect when the planet is close to its star, and hence transits more frequently. Radial velocity likewise sends its loudest signal when a planet is large and close. Microlensing, detecting the ‘bending’ of light from a background object as it is affected by a nearer star’s gravitational field, can turn up a planet whether near to its star or far,...

Astronomers said Wednesday that they had found a miniature version of our own solar system 5,000 light-years across the galaxy — the first planetary system that really looks like our own, with outer giant planets and room for smaller inner planets. “It looks like a scale model of our solar system,” said Scott Gaudi, an assistant professor of astronomy at Ohio State University. Dr. Gaudi led an international team of 69 professional and amateur astronomers who announced the discovery in a news conference with reporters. Their results are being published Friday in the journal Science. The discovery, they said, means...

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2002 December 15 A Network of Microlensing Caustics Credit & Copyright: Joachim Wambsganss (Ap. Inst. Potsdam) Explanation: A virtual sky map like this would be of interest to astronomers studying gravitational microlensing. In microlensing, the gravity of stars near the line of sight can act to magnify the light of background objects such as distant stars, or quasars. Nowhere is this magnification greater than near a gravitational lensing...