Gullies and glaciers in a crater on Mars
Click for full image.
Cool image time! The photo to the right, rotated, cropped, and reduced to post here, was taken on July 10, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows the floor of 4-mile-wide Avire Crater, located at about 41 degrees south latitude inside the much larger 185-mile wide Newton Crater.
This picture was taken as part of a long term monitoring program of the many gullies that flow down the slopes of the crater’s interior rim. In fact, the gullies of this crater have so interested scientists that one even proposed [pdf] this location as a potential future rover landing site.
Avire Crater, a small … gullied crater within Newton Crater, provides many aspects ideal to a future rover mission. It has been previously hypothesized to be the location of a former paleolake with multiple episodes of ponding and deposition. Gullies occur almost continuously on the southwest wall clockwise to the northeastern wall. Dark-toned dunes are present in the northern portion of the crater, in some places obscuring gullies while cut by gullies in others. No changes in the extent or appearance of the dunes have been observed since they were first imaged … in January of 2000. The dunes lack superimposed craters, indicating that the gullies that cut through them are geologically very youthful. Layered lobate features are present at the base of the gullies on the northern wall, seen in many other craters on Mars (not always in association with gullies), which have been suggested to have formed as terminal moraines of ice-rich flows; in Avire, these features have also been suggested to be paleolake deposits. The crater floor is obscured by mid-latitude “fill” material, hypothesized to be partially comprised of ice based on morphologic evidence that the material has been partially removed.
As gullies, dunes, and “fill” material occur in many places on Mars, a single rover mission to a site containing these features would provide valuable information applicable to thousands of other locations across the planet.
The curved ridgeline in the crater floor is thought to be a moraine. The “fill” material to the south is essentially glacial in nature. Both, as well as the gullies, appear to have been shaped either a paleolake that once existed in the crater or by cyclical glacier activity. By going to this one crater, scientists could study all these different geological features at one time.
The black cross in the overview map to the right marks the location of this crater, inside Newton Crater. Located only about 200 to 800 miles from southwest edge of the lava flood plains laid down by Mars’ biggest volcanoes, this crater sits in the southern cratered highlands. Volcanic processes might helped form the bedrock, but those processes were not directly related to those big volcanoes. The dust forming the young dunes inside the crater however could easily have come from the Medusae Fossae Formation, the planet’s largest deposit of volcanic ash that fills the lowlands to the southwest of Olympus Mons for many hundreds of miles.
Readers!
Every February I run a fund-raising drive during my birthday month. This year I celebrate my 72nd birthday, and hope and plan to continue writing and posting on Behind the Black for as long as I am able.
I hope my readers will support this effort. As I did in my November fund-raising drive, I am offering autographed copies of my books for large donations. Donate $250 and you can have a choice of the hardback of either Genesis: the Story of Apollo 8 or Conscious Choice: The origins of slavery in America and why it matters today and for our future in outer space. Donate $200 and you can get an autographed paperback copy of either.
Please consider supporting my work here at Behind the Black. My analysis of space, politics, and culture, taken from the perspective of an historian, is almost always on the money and ahead of the game. For example, in 2020 I correctly predicted that the COVID panic was unnecessary, that the virus was apparently simply a variation of the flu, that masks were not simply pointless but if worn incorrectly were a health threat, that the lockdowns were a disaster and did nothing to stop the spread of COVID. Every one of those 2020 conclusions has turned out right.
Your help allows me to do this kind of intelligent analysis. I take no advertising or sponsors, so my reporting isn't influenced by donations by established space or drug companies. Instead, I rely entirely on donations and subscriptions from my readers, which gives me the freedom to write what I think, unencumbered by outside influences.
You can support me either by giving a one-time contribution or a regular subscription. There are four ways of doing so:
1. Zelle: This is the only internet method that charges no fees. All you have to do is use the Zelle link at your internet bank and give my name and email address (zimmerman at nasw dot org). What you donate is what I get.
2. Patreon: Go to my website there and pick one of five monthly subscription amounts, or by making a one-time donation.
3. A Paypal Donation or subscription:
4. Donate by check, payable to Robert Zimmerman and mailed to
Behind The Black
c/o Robert Zimmerman
P.O.Box 1262
Cortaro, AZ 85652
You can also support me by buying one of my books, as noted in the boxes interspersed throughout the webpage or shown in the menu above.
Click for full image.
Cool image time! The photo to the right, rotated, cropped, and reduced to post here, was taken on July 10, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows the floor of 4-mile-wide Avire Crater, located at about 41 degrees south latitude inside the much larger 185-mile wide Newton Crater.
This picture was taken as part of a long term monitoring program of the many gullies that flow down the slopes of the crater’s interior rim. In fact, the gullies of this crater have so interested scientists that one even proposed [pdf] this location as a potential future rover landing site.
Avire Crater, a small … gullied crater within Newton Crater, provides many aspects ideal to a future rover mission. It has been previously hypothesized to be the location of a former paleolake with multiple episodes of ponding and deposition. Gullies occur almost continuously on the southwest wall clockwise to the northeastern wall. Dark-toned dunes are present in the northern portion of the crater, in some places obscuring gullies while cut by gullies in others. No changes in the extent or appearance of the dunes have been observed since they were first imaged … in January of 2000. The dunes lack superimposed craters, indicating that the gullies that cut through them are geologically very youthful. Layered lobate features are present at the base of the gullies on the northern wall, seen in many other craters on Mars (not always in association with gullies), which have been suggested to have formed as terminal moraines of ice-rich flows; in Avire, these features have also been suggested to be paleolake deposits. The crater floor is obscured by mid-latitude “fill” material, hypothesized to be partially comprised of ice based on morphologic evidence that the material has been partially removed.
As gullies, dunes, and “fill” material occur in many places on Mars, a single rover mission to a site containing these features would provide valuable information applicable to thousands of other locations across the planet.
The curved ridgeline in the crater floor is thought to be a moraine. The “fill” material to the south is essentially glacial in nature. Both, as well as the gullies, appear to have been shaped either a paleolake that once existed in the crater or by cyclical glacier activity. By going to this one crater, scientists could study all these different geological features at one time.
The black cross in the overview map to the right marks the location of this crater, inside Newton Crater. Located only about 200 to 800 miles from southwest edge of the lava flood plains laid down by Mars’ biggest volcanoes, this crater sits in the southern cratered highlands. Volcanic processes might helped form the bedrock, but those processes were not directly related to those big volcanoes. The dust forming the young dunes inside the crater however could easily have come from the Medusae Fossae Formation, the planet’s largest deposit of volcanic ash that fills the lowlands to the southwest of Olympus Mons for many hundreds of miles.
Readers!
Every February I run a fund-raising drive during my birthday month. This year I celebrate my 72nd birthday, and hope and plan to continue writing and posting on Behind the Black for as long as I am able.
I hope my readers will support this effort. As I did in my November fund-raising drive, I am offering autographed copies of my books for large donations. Donate $250 and you can have a choice of the hardback of either Genesis: the Story of Apollo 8 or Conscious Choice: The origins of slavery in America and why it matters today and for our future in outer space. Donate $200 and you can get an autographed paperback copy of either.
Please consider supporting my work here at Behind the Black. My analysis of space, politics, and culture, taken from the perspective of an historian, is almost always on the money and ahead of the game. For example, in 2020 I correctly predicted that the COVID panic was unnecessary, that the virus was apparently simply a variation of the flu, that masks were not simply pointless but if worn incorrectly were a health threat, that the lockdowns were a disaster and did nothing to stop the spread of COVID. Every one of those 2020 conclusions has turned out right.
Your help allows me to do this kind of intelligent analysis. I take no advertising or sponsors, so my reporting isn't influenced by donations by established space or drug companies. Instead, I rely entirely on donations and subscriptions from my readers, which gives me the freedom to write what I think, unencumbered by outside influences.
You can support me either by giving a one-time contribution or a regular subscription. There are four ways of doing so:
1. Zelle: This is the only internet method that charges no fees. All you have to do is use the Zelle link at your internet bank and give my name and email address (zimmerman at nasw dot org). What you donate is what I get.
2. Patreon: Go to my website there and pick one of five monthly subscription amounts, or by making a one-time donation.
3. A Paypal Donation or subscription:
4. Donate by check, payable to Robert Zimmerman and mailed to
Behind The Black
c/o Robert Zimmerman
P.O.Box 1262
Cortaro, AZ 85652
You can also support me by buying one of my books, as noted in the boxes interspersed throughout the webpage or shown in the menu above.
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