Comets might hold the key to how life started on earth.
The Rosetta spacecraft has discovered key building blocks of life in the dust of a comet, bolstering the possibility that life on Earth may have been brought by an extraterrestrial object flying across the vastness of the universe.
For the first time, scientists have detected presence of key organic compounds in the dust cloud carried along by a comet. The findings strongly support the notion that life may not have originated on Earth, but instead, it was delivered here by these celestial objects. These objects hurtling across galaxies could have carried and deposited chemical building blocks for life long ago to Earth. If the theory is extended, other planets in our solar system might have similarly received components to kick start and support life during their existence.
The European Space Agency’s Rosetta spacecraft made several detections of the amino acid glycine, used by living organisms to make proteins, in the cloud of gas and dust surrounding Comet 67P/Churyumov-Gerasimenko, confirmed scientists, reported Reuters. In other words, it means that in all likelihood, glycine was carried through space on the surface of the comet. Incidentally, there have been numerous instances in the past where space probes have detected the presence of glycine. However, past experiments were marred with “contamination issues” that “complicated the scientific analysis,” shared Kathrin Altwegg, one of the lead authors of a new paper in the journal Science Advances,
“This is the first unambiguous detection of glycine at a comet. Having found glycine in more than one comet shows that neither Wild 2 nor 67P are exceptions. The confirmation supports the idea that amino acids are common around star-forming regions of the universe and were likely delivered to Earth by a comet or other celestial object.”
Given the confirmed presence of glycine on a comet, Altwegg indicated that there are plenty of chances of life having evolved in other regions of the universe,
“Amino acids are everywhere, and life could possibly also start in many places in the universe”
Previous detections of glycine were indirect, and scientists were skeptical about the find. The space probe that collected the samples returned to Earth in 2006 landed in the Utah desert.
Besides the amino acid, Rosetta also discovered phosphorous, which is another key building block for life commonly found in all living organisms. The spacecraft found traces of other organic molecules which have varying importance in the formation and sustenance of life on any planet, not just Earth. The comet 67P isn’t very unique, which indicates there could be thousands or millions of such comets moving in the universe while holding the key components needed for life.
The possibility of life arriving on Earth has been discussed for quite some time. Comets and asteroids have routinely crashed on planets after being trapped by the gravitational force exerted by the relatively large and stable celestial objects. These miniature projectiles in space could easily crash into planets that contain water, a critical component for life, and that is what may have happened to Earth billions of years ago, said University of Washington astronomer Donald Brownlee, who led NASA’s Stardust comet sample return mission,
“Meteorites and now comets prove that Earth has been seeded with many critical biomolecules over its entire history.”
Technically, a lot more components than amino acids and phosphorus are needed to initiate life. A living cell needs a multitude of other basic elements to combine before it starts to live and thrive. Researchers speculate that while comets like 67P might have deposited glycine and phosphorous, other impacting celestial objects might have contributed the rest of the building blocks of life.
The Rosetta spacecraft has nearly completed its two-year mission trailing 67P Churyumov-Gerasimenko. The brave spacecraft spent a decade chasing the comet, reported the Daily Mail. It’s brethren Philae lander wasn’t able to last long on the comet’s surface. Scientists are now planning to crash the spacecraft on the comet’s surface, reported Engadget.