It’s dark outside, permanently. The sun twinkles in the distance barely bigger than other stars. But the ground is warm, and oceans are teaming with life. That’s the scenario envisioned by Dan Hooper and Jason Steffen of Fermi National Laboratory in Batavia Illinois, who released a preprint yesterday about the possibility of dark matter heating planets that are otherwise too far from their host stars to be habitable.
Hooper says the pair started out with the most optimistic assumptions possible. They considered “superearths” about ten times Earth’s mass, and located in dark matter haloes surrounding galaxies, rather than on the fringes of a spiral arm of a galaxy like our solar system is. They also imagined planets rich in iron, an element with a relatively large nucleus that dark matter particles would hit and lose their speed, collecting in the center of the planet. There pairs of the particles would annihilate, releasing radiation that then heats up ordinary matter in the center of the planet. Hooper says the conversation rate would be about 10 to the 25 particles per second, providing a power source of about 100 petawatts, similar to the amount of power we get from the Sun. “It’s at least plausible,” Hooper says, “in the same way as we can use solar power, they’d have a power source in dark matter.”
Current technology isn’t able to detect the planets, Hooper says. And no, dark matter won’t work as a power source on Earth, because there aren’t enough particles in our vicinity to capture and harness. “We thought it was personally interesting and kind of fun, but it’s not going to change anything,” Hooper says.
This blog was updated on March 30th to reflect that the power produced is 100 petawatts, not terawatts.
Image: prob1t on Flickr under Creative Commons