NASA announces there are trillions of 'rogue' Earth-sized planets wandering through our galaxy

Research from NASA and Japan's Osaka University indicates that rogue planets, worlds that aren't linked by gravity to a star, overwhelmingly outnumber the number of planets that are gravitationally linked to stars.

The scientist's findings can be traced back to a nine-year survey called Microlensing Observations in Astrophysics (MOA) which was conducted at the Mount John University Observatory located in New Zealand.

NASA explains in a blog post that due to the phenomena of mass warping the fabric of space-time, researchers are able to "microlens" objects, which is when an object comes in a near-perfect alignment with light from a distant star, the light bends around the nearest object it passes by.

More specifically, the mass of an object warping space-time acts as a natural lens allowing observers to see much further in space than they could with the instruments they are using, or in this case, learn more about the object that has come in between the observers and the light of a distant star.

According to David Bennett, a senior research scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland, and a co-author of two papers, "We estimate that our galaxy is home to 20 times more rogue planets than stars - trillions of worlds wandering alone."

"Microlensing is the only way we can find objects like low-mass free-floating planets and even primordial black holes," said Takahiro Sumi, a professor at Osaka University, and lead author of the paper with a new estimate of our galaxy's rogue planets. "It's very exciting to use gravity to discover objects we could never hope to see directly."