The icy floor of one of Mars’ most ancient craters
Click for original image.
Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on April 3, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It focuses on a small crater in the center of 265-mile-wide Greeley Crater, named in 2015 after the late Ron Greeley, who had been involved in almost every planetary mission from the 1960s until his passing in 2011.
Greeley Crater is intriguing because of its age, estimated to be about four billion years old, as indicated by crater counts and the crater’s heavily eroded condition.
This ancient crater, which has already been heavily eroded and filled with sediment, is difficult to make out against the Martian landscape due to its relatively shallow depth of only 1.5 kilometres – indeed, the crater rim has disappeared altogether in places.
Greeley is also intriguing by its location in the southern mid-latitudes. On the overview map above the red dot inside Greeley marks the location of today’s picture. This is a region with lots of evidence of ice and glacial features inside craters. The picture shows a small two-mile-wide crater about 500 feet deep inside Greeley. Both inside and outside the crater the surface suggests ice, either in glacial formations on the crater floor or as a soft flat plain that allows impacts to sink in without producing a rim or much ejecta.
While research has suggested a large number of glaciers in the outlined region on the western edge of the overview map, the evidence continues to build that near-surface ice exists everywhere throughout the mid-latitudes of Mars.
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. from any other book seller, or direct from my ebook publisher, ebookit.
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, rotated, cropped, reduced, and sharpened to post here, was taken on April 3, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It focuses on a small crater in the center of 265-mile-wide Greeley Crater, named in 2015 after the late Ron Greeley, who had been involved in almost every planetary mission from the 1960s until his passing in 2011.
Greeley Crater is intriguing because of its age, estimated to be about four billion years old, as indicated by crater counts and the crater’s heavily eroded condition.
This ancient crater, which has already been heavily eroded and filled with sediment, is difficult to make out against the Martian landscape due to its relatively shallow depth of only 1.5 kilometres – indeed, the crater rim has disappeared altogether in places.
Greeley is also intriguing by its location in the southern mid-latitudes. On the overview map above the red dot inside Greeley marks the location of today’s picture. This is a region with lots of evidence of ice and glacial features inside craters. The picture shows a small two-mile-wide crater about 500 feet deep inside Greeley. Both inside and outside the crater the surface suggests ice, either in glacial formations on the crater floor or as a soft flat plain that allows impacts to sink in without producing a rim or much ejecta.
While research has suggested a large number of glaciers in the outlined region on the western edge of the overview map, the evidence continues to build that near-surface ice exists everywhere throughout the mid-latitudes of Mars.
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. from any other book seller, or direct from my ebook publisher, ebookit. 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
I have an idea for temporarily naming all of the unnamed Craters and structures on Mars.
We are familiar with the location mountains and rivers, cities and towns in countries on earth. If we can press the land masses together (like Pangea) removing the oceans, then overlay earth over Mars… every named place on earth will correspond to a location on Mars. It would be a publicity stunt that will allow every nation and place have a corresponding region on the red planet allowing easier identification with familiarity.
I have fantasized of what the lunar colonies might name themselves… The center of the moon would be the largest probably named Luna of course. Then Gotham to the east and metropolis to the west. A religious Family orientated cultural center to the north (Xanadu? Nirvana? Valhalla?) with an amusement park or Las Vegas style Sin City to the south. Something for everyone.
The tourists will want to look up to see home, but the universities, Observatories and science centers will be looking outward to the stars on the far side of the Moon.