A Martian landscape of volcanic pimples
Click for original image.
Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken by the high resolution camera on Mars Reconnaissance Orbiter (MRO) and downloaded on August 3, 2025. Labeled as a “terrain sample,” such images are usually taken not as part of any specific research request but because the camera team needs to fill a gap in the camera’s schedule so as to maintain its proper temperature. When they do this, they always try to pick interesting targets within the time window, and usually succeed.
In this case, the camera team picked a location in the middle of Isidis Planitia, one of Mars’ four biggest basins thought to have been formed from a major impact several billion years ago, focusing on an area covered with these strange knobs that have craterlike depressions at their peaks.
According research published in 2010 [pdf], it is believed these cones — all of which are only a few feet high — are the result of volcanic activity following the impact that formed Isidis four billion years ago. In a sense, they are leftover pimples from that impact and the subsequent volcanic activity within that melted basin.
The white dot on the overview map to the right marks the location. The inset, covering a 35-mile-square area, shows that this landscape of cones extends across a wide area, and in fact covers much of Isidis Plantia’s 1,200 mile wide diameter. As I wrote in 2020 when first posting another cool image of these pimples:
The cones are thought to have formed during that volcanic period in the basin’s first billion years. Some scientists think the process that produced them was purely volcanic, others think that water ice might have also been involved. The latter theory has a problem in that it requires an ice sheet at the low equatorial latitudes of Isidis. Though this is not impossible, considering the wide swings in the planet’s rotational tilt that is thought to cause large cyclical climate changes, it has been difficult so far to come up with any scenario that makes it possible.
There is simply not enough data to determine which of these theories, if any, explains this geology. We need to go there to find out for sure.
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 original image.
Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken by the high resolution camera on Mars Reconnaissance Orbiter (MRO) and downloaded on August 3, 2025. Labeled as a “terrain sample,” such images are usually taken not as part of any specific research request but because the camera team needs to fill a gap in the camera’s schedule so as to maintain its proper temperature. When they do this, they always try to pick interesting targets within the time window, and usually succeed.
In this case, the camera team picked a location in the middle of Isidis Planitia, one of Mars’ four biggest basins thought to have been formed from a major impact several billion years ago, focusing on an area covered with these strange knobs that have craterlike depressions at their peaks.
According research published in 2010 [pdf], it is believed these cones — all of which are only a few feet high — are the result of volcanic activity following the impact that formed Isidis four billion years ago. In a sense, they are leftover pimples from that impact and the subsequent volcanic activity within that melted basin.
The white dot on the overview map to the right marks the location. The inset, covering a 35-mile-square area, shows that this landscape of cones extends across a wide area, and in fact covers much of Isidis Plantia’s 1,200 mile wide diameter. As I wrote in 2020 when first posting another cool image of these pimples:
The cones are thought to have formed during that volcanic period in the basin’s first billion years. Some scientists think the process that produced them was purely volcanic, others think that water ice might have also been involved. The latter theory has a problem in that it requires an ice sheet at the low equatorial latitudes of Isidis. Though this is not impossible, considering the wide swings in the planet’s rotational tilt that is thought to cause large cyclical climate changes, it has been difficult so far to come up with any scenario that makes it possible.
There is simply not enough data to determine which of these theories, if any, explains this geology. We need to go there to find out for sure.
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