Our galaxy, the Milky Way, is home to over 100 billion planets. There are also at least 50 billion galaxies in our universe. However, until recently, there were no known planets outside of the Milky Way galaxy.
Since we began studying the stars, scientists have uncovered over 5,000 planets beyond our own sun that are similar to Earth in some way. One of those was discovered by the NASA Chandra X-Ray Telescope, lightyears away in what is known as the Messier 51 galaxy—binary system M51-ULS-1.
What Is an Exoplanet?
An exoplanet is a planet orbiting another star than our own Sun. To be considered an exoplanet, the body must meet some very specific requirements. The planet must be massive enough to form its own gravity, and it must orbit a star or stellar remnant at a distance of more than about 10% of the average distance between Earth and our Sun (which would be roughly 150 million kilometers).
This is an amazing discovery, and many more are expected to be found in the near future. NASA has even announced that there could be 100 billion planets in our universe, outside of the Milky Way Galaxy.
Why Binary System M51-ULS-1 Is Critical to Space Exploration
As humans continue to push their reach outward into space, exoplanets will play a vital role in the future of all space exploration. Planets beyond our own solar system can be seen as laboratories to test other aspects of science and research. For example, astronomers are unsure how planets form so finding out if this is similar to how they formed around other stars would give them insight into how they formed around our own star, the sun.
This discovery proves that there are many undiscovered planets in our universe and gives hope to future space exploration. In time, scientists hope to discover intelligent life outside of our galaxy, or at least to find more planets similar to Earth with the possibility of being habitable. When we do, that would give us hope for the future of not only our planet but also the universe.