British-born astronomer Caleb Sharf has come up with a theory which suggests that planets with a biosphere usually rotate faster than lifeless celestial bodies of similar age and size.
The ‘revolutionary’ (pardon the pun) theory may become extremely helpful to astronomers searching for traces of extraterrestrial life outside our solar system.
Speaking with Space.com, Sharf, the director of the Columbia Astrobiology Center at Columbia University and author of a new study on the subject, explained that while the idea “that biology, or a biosphere, could conceivably influence the rotation of a planet by altering [its] atmospheric composition” may sound “crazy,” it actually “seems that it’s not impossible.”
Space.com explained that as life forms release gases, such as oxygen, into a planet’s atmosphere, they can speed up its rotation along its axis. Of course, Sharf admitted that an atmosphere is “much, much less dramatic” in its effects on a planet’s spin speed than other factors such as gravity pulls. Nonetheless, “over geological timescales, they can matter and they can counter the effects of things like lunar and solar gravitational tides,” he explained.
The same can be said of the impact an atmosphere has on a planet’s heating and cooling cycle, the atmosphere effectively providing “a handle, if you will, like a big wrench, for gravitational forces from the star or moons to pull on the atmosphere,” the scientist said.
The astronomer pointed out that a great deal more research still needs to be done on the subject. “What I’ve done is just lay out a plausible ‘what if’ scenario, with some educated guesses for the numbers,” he said. Future work using 3D computer models simulating the impact lifeforms have on planets can confirm or contest his hypothesis, according to Sharf.
Since the launch of the Kepler space observatory in 2009, astronomers have discovered some 2,000 planets outside our solar system, several dozens of them deemed to be in the so-called ‘habitable zone’ for life forms. The discovery has prompted astrobiologists to begin working on ways to assess these planets’ suitability for life, and to try to find its traces in their atmosphere. If Sharf’s theory is confirmed, it can help lead to a major breakthrough in the search for extraterrestrial life.