The uncertainty of science: Using a new computer model, scientists now think they have shown how on the Saturn moon Enceladus pressure from an underground ocean can push through cracks to produce geysers on the surface.
Rudolph and his colleagues ran a physics-based model to map the conditions that could allow the cracks from the surface to reach the ocean and cause the eruptions. The model accounts for cycles of warming and cooling that last on the scale of a hundred million years, associated with changes in Enceladus’ orbit around Saturn. During each cycle, the ice shell undergoes a period of thinning and a period of thickening. The thickening happens through freezing at the base of the ice shell, which grows downward like the ice on a lake, Rudolph said.
The pressure exerted by this downward-expanding ice on the ocean below is one possible mechanism researchers have proposed to explain Enceladus’ geysers. As the outer ice shell cools and thickens, pressure increases on the ocean underneath because ice has more volume than water. The increasing pressure also generates stress in the ice, which could become pathways for fluid to reach the surface 20-30 kilometers away.
You can read the paper here.
Be warned: This is only a model. Moreover, its conclusions suggest that this mechanism will not work on Jupiter’s moon Europa, which has many planet-wide crack-like features that suggest (as yet unconfirmed) a bubbling up from below.
From the press release: In this ground-breaking new history of early America, historian Robert Zimmerman not only exposes the lie behind The New York Times 1619 Project that falsely claims slavery is central to the history of the United States, he also provides profound lessons about the nature of human societies, lessons important for Americans today as well as for all future settlers on Mars and elsewhere in space.
Conscious Choice: The origins of slavery in America and why it matters today and for our future in outer space
, is a riveting page-turning story that documents how slavery slowly became pervasive in the southern British colonies of North America, colonies founded by a people and culture that not only did not allow slavery but in every way were hostile to the practice.
does more however. In telling the tragic history of the Virginia colony and the rise of slavery there, Zimmerman lays out the proper path for creating healthy societies in places like the Moon and Mars.
“Zimmerman’s ground-breaking history provides every future generation the basic framework for establishing new societies on other worlds. We would be wise to heed what he says.” —Robert Zubrin, founder of founder of the Mars Society.
Available everywhere for $3.99 (before discount) at Amazon, Barnes & Noble, and all ebook vendors, or direct from the ebook publisher, ebookit. And if you buy it from ebookit you don't support the big tech companies and I get a bigger cut much sooner.