The first ever alien object to enter the Solar System may hold interstellar water in it, a study suggests.
The asteroid, named ‘Oumuamua, was discovered on October 19, and its speed and trajectory is strong proof that it’s not from this star system, the BBC reports. The mass showed no signs of “outgassing” as it neared the sun, further strengthening the proposal that it little, if any, water or ice.
The latest findings, however, suggest that there might be water trapped under a thick, carbon-rich coating on the body’s surface. This comes from signals beamed to a radio telescope, as astronomers at the Breakthrough Listen initiative have been searching across different radio frequency bands that might indicate anything in alien technology.
Preliminary results have drawn a blank, so far. They did measure the way that ‘Oumuamua reflects sunlight and found that it is similar to icy objects in the Solar System that contain a dry crust.
Alan Fitzsimmons, one of the study authors from Queen’s University Belfast, said, “We’ve got high signal-to-noise spectra (the ‘fingerprint’ of light reflected or emitted by the asteroid) both at optical wavelengths and at infrared wavelengths. Putting those together is crucial.” He added,
What we do know is that the spectra don’t look like something artificial.
According to the measurements, millions of years of exposure to cosmic rays have formed an insulating, carbon-rich layer on the asteroid that could have made a shield around an icy interior, preventing exposure to the sun. this process of irradiation has left a reddish color on ‘Oumuamua, much like what happens to objects in the frozen fringes of the solar system.
“When it was near the Sun, the surface would have been 300C (600 Kelvin), but half a meter or more beneath the surface, the ice could have remained,” Fitzsimmons said.
Initial measurements suggest this object is at least 10 times longer than it is wide, making it more extreme than any other space body ever observed. There are doubts regarding its size, though. “We don’t know its mass and so it could still be fragile and have a relatively low density. That would still be consistent with the rate at which it is spinning – which is about once every seven-and-a-half hours or so. Something with the strength of talcum powder would hold itself together at that speed,” Fitzsimmons explained.
The study was published in Nature Astronomy.