mikrolensing

Mikrolensing is a phenomenon in astrophysics where the gravitational field of a star or other compact object causes the light from a distant source to be magnified and distorted. This effect is analogous to the more familiar gravitational lensing, but on a much smaller scale. The term "mikrolensing" comes from the Greek word "mikros," meaning small.

The primary application of mikrolensing is in the search for extrasolar planets. When a planet orbits a star, it can act as a secondary lens, further magnifying and distorting the light from the background source. This results in a characteristic light curve, which can be used to infer the presence and properties of the planet. The first confirmed detection of an extrasolar planet using this method was in 1993.

Mikrolensing can also be used to study the structure and distribution of dark matter in galaxies and galaxy clusters. The gravitational field of dark matter can cause additional distortions in the light from background sources, which can be used to map out the distribution of dark matter.

The microlensing effect is typically very small, requiring precise measurements and sophisticated analysis techniques to detect and study. The first microlensing event was observed in 1989, and since then, numerous events have been detected and studied using ground-based and space-based telescopes.