Astronomers have found what they say are two free-floating alien Planets in the Milky Way Galaxy, each without any star to orbit.
Furthermore, astronomers predict there could be millions of such planets in the universe.
Scientists do not know exactly how far from the solar system they are located, but they have been able to estimate their possible size.
One of the rogue planets lacking a home star is the size of our plant, while the other alien world is believed to be the size o Jupiter.
According to an article published earlier this November on the prepress server (from the magazine Astronomy & Astrophysics), the team calculated that next to these celestial bodies “there is no star companion” at distances of at least 6.0 units astronomical from one of the planets and 3.9 units of the other.
Spotting the Rogue Planets
The highlight in this investigation is the method that allowed the detection of both exoplanets.
The new ‘rogue Planets’ were found in data from the Optical Gravitational Lensing Experiment (OGLE).
Cosmological theories predict the existence of this class of “independent” planets, which would have been expelled by their parent systems.
Finding them is a problem.
When searching for exoplanets, astronomers rely on the dips in brightness that occur as potential planets transit their stars.
Without these dips in brightness, it’s extremely difficult to spot any exoplanets.
Planets that do not orbit stars emit little or no light, but their presence can be seen from Earth only because of the barely visible distortion of light coming from distant galaxies.
This is why researchers rely on a technique called gravitational microlensing.
This means that scientists look for tell-tale signs when the potential planet’s gravity acts like a giant cosmic magnifying lens bending the background light coming from a star.
“While making statistical inferences out of such a small sample of events is risky, we show that these detections are consistent with low-mass lenses being common in the Milky Way unless the fact that events occurred on bright giant stars is just a coincidence,’ the researchers note in the paper.”
But despite possible uncertainties, astronomers explain that their discovery follows predictions of planet formation theories.
Astronomers argue that the ‘rogue worlds’ were most likely ejected from their parent star system a very long time ago.
“Our findings support conclusions that such Earth-mass free-floating (or wide-orbit) planets are more common than stars in the Milky Way,” explain astronomers.