Distance of a Microlensing Event Measured For the First Time

astroengine writes For the first time, astronomers have combined the observational power of a ground-based survey with a space telescope to measure the distance to a stellar-mass object that was detected through a chance microlensing event. In a new paper published in The Astrophysical Journal, astronomer Jennifer Yee of the Harvard-Smithsonian Center for Astrophysics (CfA), Mass., led the study focusing on the detection of the microlensing event called "OGLE-2014-BLG-0939." Detected by the 1.3 meter Warsaw Telescope at the Las Campanas Observatory in Chile and alerted through the Optical Gravitational Lens Experiment (OGLE) community on May 28, 2014, Yee's team seized the opportunity to use NASA's Spitzer Space Telescope to focus on the transient brightening. Both telescopes recorded a light curve of the event and was therefore able to derive the distance to the dark lens.

Comments

10,200 Light Years Away

[sycodon]

Now you don't have to RTFA.

Re:20 years late

[cusco]

I broke the rules and RTFA, this is the first time that they have managed to combine an Earth-based observation and a space-based one separated by far enough from each other to give a reasonably accurate baseline for an accurate measurement of both distance and mass. From the article:

Calculations estimated it to be 10,200 (+/- 1,300) light-years away. . . These observations also allowed the mass of the object to be measured — around 0.23 solar masses