What are the well -known extrasolar planets?

Extrasolar planet or exoplanet is a planet in the solar system different from our own. We have always assumed that they exist, but until 1992 the presence of the extrasolar planet was definitely confirmed. Another discovery was done a little earlier, in 1988, but it would not be confirmed until 2003. The discovery of 1992, which was radio astronomers Aleksander Wolszczan and Dale Frail, revealed the planetary system around the rapid rotating Pulsar PSR 1257+12. It is assumed that these unusual planets have either formed from the remnants of the supernova explosion that created pulsar, or otherwise were rocky cores of gas giants whose atmosphere was deprived of supernovni. He discovered an extrasolar planet orbiting the main sequence (Sun -like Sun), 51 Pegasi, about 50 lights. The planet was discovered using a radial speed method that uses a sensitive spectroscope to detect regular speed changes in the spectral stars line with a size of up to 70 meters per second.The planet was named 51 Pegasi B, the name Convention used for all extrasolar planets. The first extrasolar planet orbiting the star is marked "B", the second "C", the third "D" and so on.

51 Pegasi B was an interesting example of the extrasolar planet, because it was very massive, about half of Jupiter-Asi 150 times larger than Earth on Earth-but orbits exceptionally close to its home star, only 0.05 Au, about the eighth small than the distance between Mercury and the Sun. 51 Pegasi B orbits its home star every four days. This discovery forced astronomers to acknowledge that such a planet - a massive and small orbit - could exist. Before that, the thoughts of that massive planet were created further in solar systems, as we observe ourselves.

This class of planets has become known as "hot jupiters" because of their great heat and matter. Many other hots were discovered in the following yearsJupiters, which forces scientists to study how much planets can engage in orbital migration - forming in the external range of the star system and then migrate inside. The question is still not entirely answered.

Another class of discovered extrasolar planets is known as Super-Země. Given the sensitivity of our current detection methods, these are the smallest extrasolar planets that we have discovered - planets with 2 and 10 Earth's masses (although the definition differs). Discovered the first two exoplanets, PSR B1257+12 B and PSR B1257+12 ° C, are super-země, each with a matter of about 4 times larger than the ground. Several other super land has been discovered since then. The most remarkable is the Gliese 581 C, discovered in April 2, a team led by Stephane Sain based in Switzerland.

This was the first super-country to be discovered in the habitable zone of the star, which means that its surface temperature is probably between 0 and 40 degrees Celsius without taking into account any possible atmosphere. This is the first discoveredThe extrasolar planet that could be habitable for people and it will not be the last.