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How many rogue planets are there in the universe?

How many rogue planets are there in the universe?

By daniele

On December 22, 2021, Astronomers announced that they had discovered 70 to 170 rogue planets that are not currently orbiting their star. This Jupiter-sized planet is located in the Milky Way Galaxy region called the OB Scorpio cluster. Thus, the newly discovered free-floating planet is almost twice as large as the already known rogue planet.

Our Milky Way Galaxy has between 100 billion and 400 billion stars. Scientists say there may be as many or more planets around those stars. But think about it now. Researchers at Ohio State University have released a new study that suggests there may be more free-floating planets (rogue planets) that do not orbit around any star than stars in the Milky Way. Wow!

The new method of detecting floating planets

  • Until now, floating planets have been discovered by micro-lens exploration. With this method, you see the planet and the background star overlap for a moment. However, it is impossible to follow the microlens phenomenon that can be observed only once with this method.
  • Last year, another study estimated that there could be 50 billion such nomadic planets in the galaxy. There are ten or so rogue planets that have been confirmed so far. Two planets, called OGLE-2012-BLG-1323 and OGLE-2017-BLG-0560, were announced last year.
  • It is estimated that the former has a mass between Earth and Neptune and the latter between Jupiter and a brown dwarf.
  • It is difficult to find the planets around a star, especially rogue exoplanets. How does Roman find it? It uses a technique called a gravitational lens.
  • This object uses the gravity of stars and planets to bend and magnify the light from the stars that pass behind them. 
  • This technology is based on Einstein’s general theory of relativity, which can detect exoplanets thousands of light-years away from Earth. 
  • According to co-author Matthew Penney of Louisiana State University in Baton Rouge.