Only a few Planets were known in 2000 and they were in our own Solar System. They form two categories, one is the small rocky planets in the inner Solar System and the other is cold gaseous Planets located in the outer part. With the new findings, we get a new understanding of our solar system. This study was published in the Astrophysical Journal letter.
According to the data from the Kepler mission has shown that large, gaseous exoplanets can orbit very close to their star; this is the same case in our Solar System, causing them to reach temperatures exceeding 727 degrees Celsius. These have been dubbed hot Jupiters. While most other exoplanets are smaller, between the size of Neptune and Earth, we don’t know much about their composition.
There are two main methods to study exoplanet atmospheres. In the transit method, researchers can pick up stellar light that is filtered through the exoplanet’s atmosphere when it passes in front of its star, revealing the fingerprints of any chemical elements that exist there.
The other method to investigate a planet is during the eclipse. when it passes behind its host star. Planets also emit and reflect a small fraction of light, so by comparing the small changes in the total light when the planet is hidden and visible, we can extract the light coming from the planet. Both experiments are performed at different wavelengths of colors.