New Theory Explains Seeds Of Life In Asteroids; Disputes Theory Taught In Schools For Decades
Oct 02, 2013 01:30 PM EDT
A new study gives a new explanation for how the "seeds of life" were able to form inside of asteroids.
The researchers believe their conclusions will replace the outdated theory of how biomolecules form, a Rensselaur press release reported.
The asteroid belt between Mars and Jupiter is now a dry and barren wasteland, but researchers believed it was once wet, warm, and perfect for spawning biomolecules. Scientists have found traces of these organisms in rocks from the asteroid belt, meaning the conditions must have been favorable for the biomolecule's growth.
"The early sun was actually dimmer than the sun today, so in terms of sunlight, the asteroid belt would have been even colder than it is now. And yet we know that some asteroids were heated to the temperature of liquid water, the 'goldilocks zone,' which enabled some of these interesting biomolecules to form," Wayne Roberge, a professor of physics within the School of Science at Rensselaer, and member of the New York Center for Astrobiology, who co-authored a paper on the subject, said. "Here's the question: How could that have happened? How could that environment have existed inside an asteroid?"
There are two commonly taught theories on how asteroids could have been heated, one claims the area heated in a way similar to the Earth's core, and the other theory involves interactions between plasma and magnetic fields.
The researcher's new theory claims that when an asteroid moves through a magnetic field it experiences and electric field, which would push electric currents through the asteroid and heat it.
"It's a very clever idea, and the mechanism is viable, but the problem is that they made a subtle error in how it should be applied, and that's what we correct in this paper," Roberge said. "In our work, we correct the physics, and also apply it to a more modern understanding of the young solar system."
"The mechanism requires some extreme assumptions about the young solar system," Ray Menzel, a graduate student in physics and co-author, said. "They assumed some things about what the young sun was doing which are just not believed to be true today. For example, the young sun would have had to produce a powerful solar wind which blew past the asteroids, and that's just no longer believed to be true."
The solar winds and plasma stream are not believed to have been as strong as scientists once thought.
"We've calculated the electric field everywhere, including the interior of the asteroid," Roberge said. "How that electric field comes about is a very specialized thing; about 10 people in the world study that kind of physics. Fortunately, two of them are here at RPI working together."
One mechanism in the process is called multi-fluid magneto-hydrodynamics. Magneto-hydrodynamics is the study of how charged fluids such as plasma interact with magnetic fields.
"The neutral particles interact with the charged particles by friction," Menzel said. "So this creates a complex problem of treating the dynamics of the neutral gas and allowing for the presence of the small number of charged particles interacting with the magnetic field."
"We're just at the beginning of this. It would be wrong to assert that we've solved this problem," Roberge said. "What we've done is to introduce a new idea. But through observations and theoretical work, we know have a pretty good paradigm."