Astronomers find two classes of gas giant planets

According to the NASA Exoplanet Archive, astronomers have found 3,498 confirmed exoplanets as of June 29, 2017. Of those planets, 679 have measured masses, and 281 have masses greater than 300 times that of Earth (Jupiter’s mass is nearly 318 times that of Earth). As more planets circling other stars are discovered, astronomers are now hoping to use the increased statistics to understand how those planets form in the first place. And recent work has now found evidence for at least two formation mechanisms behind the growth of giant planets in extrasolar systems.

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