Writing in Nature, they say they have found ten Jupiter-sized objects that they may not connect with any solar system. They also believe such objects could be as common as stars are throughout the Milky Way.
The objects revealed themselves by bending the light of more distant stars, an result known as "gravitational microlensing".
Objects of enormous enough mass can bend light, as Albert Einstein predicted. If a large object passes in front of a additional distant background star, it might act as a lens, bending and distorting the light of that star therefore that it might seem to brighten significantly.

The researchers examined knowledge collected from microlensing surveys of what is referred to as the Galactic Bulge, the central space of our own Milky Way.

Using the data, they found proof of ten Jupiter-sized objects with no parent star detected within 10 Astronomical Units (AU). One AU is such as the space between our Earth and Sun.
Further analysis led them to the conclusion that most of those objects did not have parent stars.
'Common' objects Based on the quantity of such bodies in the world surveyed, the astronomers then extrapolated that such objects could be extraordinarily common.

They calculated that they could be virtually twice as common as "main-sequence stars" - like our own Sun - that are still burning through their hydrogen fuel stock.
Co-author Takahiro Sumi, an associate professor at Osaka University in Japan, said these free-floating planets were "very common, as common as a daily star".

The "rogue" planets act as lenses, bending the light from distant stars

"The subsistence of free-floating planets like this can be expected from planetary formation theory. What's surprising is how common they seem to be."
According to astronomical convention, planets orbit a star or stellar remnant, therefore if these objects do not have a bunch star, then they're not technically planets, even if they may have formed in the identical approach as what we have a tendency to decision planets.
Indeed, the researchers hypothesise these objects were formed during a planetary disc, just like the planets in our own Solar System, before gravitational forces ejected them from these systems.

Professor Joachim Wambsganss of the University of Heidelberg in Germany, who reviewed the study for Nature, said this was the "most plausible theory". But, he added there was a minority read that planets may kind the identical method that stars do, but fail to reach the essential purpose of thermonuclear ignition.
He too agreed the foremost "stunning" element of the information was the projected frequency of such objects.
Dr Martin Dominik of the University of St Andrews in Scotland agreed, and said he would be "a small amount cautious" about the results.
"There is that this theory that planets shaped around a star and due to the gravitational effects between planets, one in all them gets ejected from the system, thus folks have predicted that there are planets out there that are no longer sure to stars," he said.
"But they do not predict this range of them."