Showing posts with label he-3. Show all posts
Showing posts with label he-3. Show all posts

Tuesday, October 06, 2015

Explaining the Helium-3 Enrichment of the Eocene-Oligocene Boundary With Gould's Belt

Gould’s Belt, interstellar clouds, and the Eocene–Oligocene helium-3 enhancement

Author:

Rubincam

Abstract:

Drag from hydrogen in the interstellar cloud which formed Gould’s Belt may have sent interplanetary dust particle (IDPs) and small meteoroids with embedded helium to the Earth, perhaps explaining part the helium-3 flux increase seen in the sedimentary record near the Eocene–Oligocene transition. Assuming the Solar System passed through part of the cloud, IDPs in the inner Solar System may have been dragged to Earth, while dust and small meteoroids in the asteroid belt up to centimeter size may have been dragged to the resonances, where their orbital eccentricities were pumped up into Earth-crossing orbits; however, this hypotheses does not explain the Popigai and Chesapeake Bay impacts.

Monday, September 28, 2015

Mining Helium-3 on the Moon is Nonsensical

In recent years the subject of sending humans back to the Moon has largely gone mute, initially overwhelmed by talk of NASA’s Asteroid Redirect Mission, and more recently by the agency’s media drumbeat about sending humans to Mars. Because of this, there is also subsequently very little talk about a weird bit of magical thinking that often accompanies discussions of humans on the Moon: mining the Moon for helium-3 to power nonexistent fusion reactors. But that magical thinking still lurks, like a small burning ember in a burned-down house, waiting for a chance to flare up again. Last month at the Mars Society convention in Washington, DC, the subject of helium-3 briefly sparked once more, brought up by one of its longtime proponents, Apollo astronaut Harrison Schmitt.

Schmitt is probably the smartest astronaut who walked on the Moon, and certainly the most educated. He is a Harvard-trained geologist who NASA admitted to the Apollo program under pressure from Congress, and his presence undoubtedly increased the scientific return of his Apollo 17 mission as well as the entire program considering his role in training astronauts on earlier missions. Schmitt can still deliver graduate-level geology lectures if given the opportunity. But he also embraces the dubious scientific and engineering idea of mining helium-3 on the Moon for use in fusion reactors.

The last big flurry of articles and publications, and even a congressional hearing, about helium-3 fusion occurred in 2007, when NASA was still planning to send humans to the Moon. NASA did not drive that discussion then, but rather Schmitt and a few others. But even eight years later helium-3 still pollutes the environment of discussions about human spaceflight, despite its very nebulous assumptions.