Tuesday, March 14, 2006
OGLEing Neptune-sized planets for MicroFUN
You can read the full article at Arxiv astro-ph/0603276 by choosing one of the download options (the PDF file is here). Neither the OGLE nor the microFUN home pages mention the discovery yet. In gravitational microlensing, a foreground star's gravity well magnifies a background stars light, if there are planets around the lensing star, the brightening will be distorted in specific ways, depending on the size of the planet. The microlensing method is most sensitive between 2-4 AU out, so don't expect Earth size planets to be picked up soon, but it nicely complements both the radial velocity and transit methods of detecting exoplanets.
While the ABC release calls the planet "Earth like", we have no idea if it is a gas dominated world like Neptune, of a bare rock and ice core.