One of the hottest topics in Astronomy is EXOPLANETS founding.
Finding exoplanets are the first steps in order to find life in our universe!!!
There are many methods in order to find the exoplanets,like astometry, spectroscopy, straight observation and...
A new physical method is gravitational microlensing mainly become in attention after founding of OGLE group by Alcock et al . published in Nature which they found and exoplanet by this method for the first time.
The story is the old one of Einstein's bending light story.When a light ray pass by from a massive object /in this case the gravitational lens a star a galaxy or cluster of galaxies/ light beams bend, consequently the shape and flux magnitude of images of the source are altered,this phenomena is named as gravitational lensing.
In 1919 Eddington's observation of gravitational lensing is the first stone like prove of general relativity view of nature.
But what is gravitational microlensing. When the lens is a star which magnify the energy flux of a distant source caused to microlensing effect.The naming comes after the situation that the effect of light bending produce new images of source which are separated in sky by micro seconds angle,which with our nowadays technology is hard to detect. So the only effect we will see is the magnification of light.
Now this method is used to finding exoplanets. If the lens is consisting of a star and planet the magnification curve which is called after Paszynski is lost its symmetry and a bump appear in it
which is a first clue of an binary lens, maybe a exoplanet!!!
This method is fine in order to find planets of less mass which will be suitable for finding life there. Anyhow this method needs tremendous effort in computer work, curve analysis and data management.
But the news is that Martin Dominik professor of physics from Saint Andrews which is a really expert in gravitational microlensing and exoplant finding/see the second link/ visiting Tehran, and has nice couple of lectures in IPM in 10-11 September.
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