Posts Tagged ‘gravitational microlensing’
Detecting Exoplanet Moons with Gravitational Microlensing
In a paper to be published in Astronomy and Astrophysics, available online now here, astronomers have concluded that exoplanetary moons should be detectable using orbiting satellite telescopes and a technique known as gravitational microlensing. This technique, a refinement of gravitational lensing, applies Einstein’s General Theory of Relativity and its curvature of space effect on the path that the light will follow. Although the technique has only been used to discover a very small percentage of the 430 or so known exoplanets, it apparently may be ultimately used to discover moons orbiting exoplanets, where the other techniques cannot accomplish this feat. The paper is provides the reader an excellent overview of gravitational lensing, gravitational microlensing and its link to the experiments done almost a century ago to first demonstrate that Einstein’s General Theory of Relativity was correct.
Gravitational Microlensing and the Search for Earth-like Exoplanets
In a white paper released yesterday, available online now here, astronomers address the question of where in the sky would be good candidates for observing the micro-lensing effects of exoplanets. Gravitational micro-lensing is a technique which utilizing the General Relativisitic effect that gravity has on light, allowing any massive object to act like a lens if directly in line with light from a more distant object. The authors argue that “out of the five popular planet detection techniques,
Gravitational Microlensing is the most capable of detecting rocky, earth-sized planets and seems to be more promising in the search for other habitable worlds.” Thus, they offer to astronomers “a distribution map for probability of finding stars within the Milky Way Galaxy that could harbor terrestrial planets capable of hosting life, with a particular emphasis on the Microlensing detection of exoplanets.”