Interstellar Object 'Oumuamua Could Be a Comet in Disguise

  • Interstellar Object 'Oumuamua Could Be a Comet in Disguise

Interstellar Object 'Oumuamua Could Be a Comet in Disguise

Scientists announced the asteroid in November - the first discovered that had an origin outside our solar system. "I imagine the carbon-rich layer would be inhospitable to life due to the large radiation dose it has received", Alan Fitzsimmons, an astrophysicist at Queen's University Belfast in the United Kingdom and lead author of the paper published (paywall) in Nature today (Dec. 18), told Quartz via email.

In a statement last week, the $100m (£75m) Seti project Breakthrough Listen said: "Researchers working on long-distance space transportation have previously suggested that a cigar or needle shape is the most likely architecture for an interstellar spacecraft, since this would minimise friction and damage from interstellar gas and dust". It's possible that others which have yet to be identified are also immigrants to our solar system.

Scientists led by Professor Stephen Hawking, in a programme called Breakthrough Listen, even used high-tech scanners to discover if the object was sent by an alien civilisation - although they also couldn't find any evidence of this.

Scientists from Queen's University Belfast led an worldwide team of astronomers - from Britain, the United States, Canada, Taiwan and Chile -tasked with piecing together a profile of 'Oumuamua.

Dr Michele Bannister, whose research is published in Astrophysical Journal Letters, said the rock "looks so much like a tiny world from our own home system".

"Given that this object passed relatively close to our sun as it was travelling through our solar system, one would expect any ices on the surface to basically be heated and it should behave like a comet", Fitzsimmons said.

She said: 'This object went past the sun and it was only heated like a good oven cooking a cake. "I struggle to imagine how life could live at the frigid temperatures that would exist within a small object in interstellar space", he told Quartz. It wasn't particularly hot.

"This surface layer is what happens if you take comet ices and comet dust grains and bake them with high energy particles for millions or even billions of years", said Fitzsimmons.

But this comet appears to orbit at an angle, and doesn't circle the sun.

Cosmic radiation given off by things like other galaxies or supernovae has essentially baked the layer of carbon tightly onto the rest of the asteroid's body, insulating it with the equivalent of a celestial oven spill.

The studies show that 'Oumuamua more effectively reflects reddish light than bluish light-a roundabout outcome of high-energy particles flung off as shrapnel from cosmic cataclysms such as supernovae.

Spectroscopic readings revealed it sported a half-metre (1.6-foot) coat of organic-rich material which could have protected a water-ice interior from being vaporised by the Sun.

Seven researchers have been observing the object since its discovery and have concluded it is a lump of rock, albeit one with unusual features. The word means scout in Hawaiian.

"So this is a little tangible piece of evidence that the way plants formed and grew in our solar system, it's happening the same way in other solar systems far away".

She said: 'None of the astronomers have ever talked about it being anything alien, except that it comes from outside the solar system'. Astronomers couldn't find any traces of a comet tail around 'Oumuamua, though, so the rock was reclassified as an asteroid.