Ancient lava flows down the flanks of the solar system’s largest volcano
Click for full image.
Cool image time! The photo to the right, cropped, reduced, and sharpened to post here, was taken on October 2, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what appears to be very old and eroded lava on the northeast flanks of Olympus Mons, the largest volcano on Mars as well as the entire solar system. About 600 miles across, from the edge to its peak, Olympus rises about 54,000 feet, with an actual height relative to Mars’ “sea level” of just under 70,000 feet, more than twice as high as Mount Everest on Earth.
The white arrow show the downward grade. Several different flows can be seen throughout the picture, some confined to a central channel with smooth aprons of overflows on either side. Others are more broken and less coherent, and suggest that either the flows were inherently different, or are much older and have deteriorated with time.
The white box in the overview map to the right marks this picture’s location, on the northeast flank of the mountain.
The eruptions that created this volcano are thought to have occurred from 2 to 4 billion years ago, though some younger flows only 2 to 115 million years ago are suspected to exist on its northwest quadrant. Because it is a shield volcano, it was created by many eruptions, with lava flowing great distances again and again down its slopes. Thus, the picture above might be showing us many of these flows over time.
In Mars’ low gravity, about 39% of Earth’s, the data suggests that lava flows faster and with less viscosity. It is therefore possible for a single flow to travel several hundred miles, from the caldera down these slopes to the volcano’s edge, before freezing. At the same time, there is also evidence of additional vents along those flanks, which would have contributed their own flows.
Imaging what Mars was like when this volcano was active is difficult. Each eruption would have likely changed the planet’s entire climate.
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 print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. 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
Click for full image.
Cool image time! The photo to the right, cropped, reduced, and sharpened to post here, was taken on October 2, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what appears to be very old and eroded lava on the northeast flanks of Olympus Mons, the largest volcano on Mars as well as the entire solar system. About 600 miles across, from the edge to its peak, Olympus rises about 54,000 feet, with an actual height relative to Mars’ “sea level” of just under 70,000 feet, more than twice as high as Mount Everest on Earth.
The white arrow show the downward grade. Several different flows can be seen throughout the picture, some confined to a central channel with smooth aprons of overflows on either side. Others are more broken and less coherent, and suggest that either the flows were inherently different, or are much older and have deteriorated with time.
The white box in the overview map to the right marks this picture’s location, on the northeast flank of the mountain.
The eruptions that created this volcano are thought to have occurred from 2 to 4 billion years ago, though some younger flows only 2 to 115 million years ago are suspected to exist on its northwest quadrant. Because it is a shield volcano, it was created by many eruptions, with lava flowing great distances again and again down its slopes. Thus, the picture above might be showing us many of these flows over time.
In Mars’ low gravity, about 39% of Earth’s, the data suggests that lava flows faster and with less viscosity. It is therefore possible for a single flow to travel several hundred miles, from the caldera down these slopes to the volcano’s edge, before freezing. At the same time, there is also evidence of additional vents along those flanks, which would have contributed their own flows.
Imaging what Mars was like when this volcano was active is difficult. Each eruption would have likely changed the planet’s entire climate.
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 print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. 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