Another model attempts to show how liquid water could have once existed on Mars
The uncertainty of science: Scientists today published a new model that attempts to show how it was possible in the distant past for liquid water to have existed on the surface of Mars.
New research published in Earth and Planetary Science Letters suggests that Mars was born wet, with a dense atmosphere allowing warm-to-hot oceans for millions of years. To reach this conclusion, researchers developed the first model of the evolution of the Martian atmosphere that links the high temperatures associated with Mars’s formation in a molten state through to the formation of the first oceans and atmosphere. This model shows that — as on the modern Earth — water vapor in the Martian atmosphere was concentrated in the lower atmosphere and that the upper atmosphere of Mars was “dry” because the water vapor would condense out as clouds at lower levels in the atmosphere. Molecular hydrogen (H2), by contrast, did not condense and was transported to the upper atmosphere of Mars, where it was lost to space. This conclusion – that water vapor condensed and was retained on early Mars whereas molecular hydrogen did not condense and escaped – allows the model to be linked directly to measurements made by spacecraft, specifically, the Mars Science Laboratory rover Curiosity.
As a model, this theory proves nothing, though it is very intriguing. The scientists propose that the heat from the planet’s interior replaces the known lack of energy that came from the Sun in Mars’ far past. While this could work, what makes it very uncertain is that its surface data is based on a single measurement from Curiosity, hardly a deep and convincing baseline.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
The uncertainty of science: Scientists today published a new model that attempts to show how it was possible in the distant past for liquid water to have existed on the surface of Mars.
New research published in Earth and Planetary Science Letters suggests that Mars was born wet, with a dense atmosphere allowing warm-to-hot oceans for millions of years. To reach this conclusion, researchers developed the first model of the evolution of the Martian atmosphere that links the high temperatures associated with Mars’s formation in a molten state through to the formation of the first oceans and atmosphere. This model shows that — as on the modern Earth — water vapor in the Martian atmosphere was concentrated in the lower atmosphere and that the upper atmosphere of Mars was “dry” because the water vapor would condense out as clouds at lower levels in the atmosphere. Molecular hydrogen (H2), by contrast, did not condense and was transported to the upper atmosphere of Mars, where it was lost to space. This conclusion – that water vapor condensed and was retained on early Mars whereas molecular hydrogen did not condense and escaped – allows the model to be linked directly to measurements made by spacecraft, specifically, the Mars Science Laboratory rover Curiosity.
As a model, this theory proves nothing, though it is very intriguing. The scientists propose that the heat from the planet’s interior replaces the known lack of energy that came from the Sun in Mars’ far past. While this could work, what makes it very uncertain is that its surface data is based on a single measurement from Curiosity, hardly a deep and convincing baseline.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
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