Plato Crater on the Moon
Cool image time! The Lunar Reconnaissance Orbiter (LRO) science team this week released a new high resolution image of the western rim of 63-mile-wide Plato Crater, located near the visible edge of the Moon’s near side. On the right is a slightly reduced version cropped to show the area of most interest.
Plato crater is prominent, yet from our vantage point on Earth we never truly see it as it is. That’s because it is located far enough north of the lunar equator (center latitude 51.62°N, center longitude 350.62°E) on the curving surface of the spherical Moon that it appears foreshortened. Plato is round like most other impact craters, but from Earth we see it as an oval aligned east to west.
A dark floor makes 101-kilometer-wide Plato crater stand out against a light-colored lunar highlands background. Plato crater is also prominent by association; the crater is located just north of 1145-kilometer-wide Mare Imbrium. A small part of this mare is visible at lower left in our Featured Image. Mare Imbrium is made up of many basalt layers laid down by violent volcanic episodes over a span of about 1.5 billion years. The basalts fill the Imbrium Basin, which a large asteroid or comet impact excavated about 3.85 billion years ago. When we look at a bright full Moon, round dark Mare Imbrium captures our gaze, then we see Plato crater, which is estimated to be about a hundred million years younger than the Imbrium Basin.
The western rim of Plato crater — visible on the east (right) side of our Featured Image — includes a 23.4-kilometer-wide slump block. The roughly triangular piece of rim broke free when an asteroid impact excavated Plato crater. Its eastern edge stands up to 1.4 kilometers above the crater’s dark floor. Part of the floor is visible in the image just above right center, east of the long shadow of the rim. [emphasis mine]
That block is thus 14.5 miles wide, and almost a mile high. I am trying to imagine what it was like when it broke off the rim and fell eastward into the crater floor. I am having trouble doing so.
Below is a image of the entire crater, with the area of the image above indicated by a white box. It shows clearly how this crater splashed into the basalt lava plain of Mare Imbrium.
The asymmetrical pattern of debris surrounding the crater, mostly to the northeast, suggests the impact came from the southwest. The crater’s smooth floor also suggests that it caused the basalt in the mare to melt into a smooth pond of lava, which then solidified. The pit and rill to the west of the rim could have formed from lava drainage out of the crater and down into Mare Imbrium, though this is only a theory.
If you go to the link above, you can zoom into this image close enough to see individual boulders only tens of feet across.
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.
Cool image time! The Lunar Reconnaissance Orbiter (LRO) science team this week released a new high resolution image of the western rim of 63-mile-wide Plato Crater, located near the visible edge of the Moon’s near side. On the right is a slightly reduced version cropped to show the area of most interest.
Plato crater is prominent, yet from our vantage point on Earth we never truly see it as it is. That’s because it is located far enough north of the lunar equator (center latitude 51.62°N, center longitude 350.62°E) on the curving surface of the spherical Moon that it appears foreshortened. Plato is round like most other impact craters, but from Earth we see it as an oval aligned east to west.
A dark floor makes 101-kilometer-wide Plato crater stand out against a light-colored lunar highlands background. Plato crater is also prominent by association; the crater is located just north of 1145-kilometer-wide Mare Imbrium. A small part of this mare is visible at lower left in our Featured Image. Mare Imbrium is made up of many basalt layers laid down by violent volcanic episodes over a span of about 1.5 billion years. The basalts fill the Imbrium Basin, which a large asteroid or comet impact excavated about 3.85 billion years ago. When we look at a bright full Moon, round dark Mare Imbrium captures our gaze, then we see Plato crater, which is estimated to be about a hundred million years younger than the Imbrium Basin.
The western rim of Plato crater — visible on the east (right) side of our Featured Image — includes a 23.4-kilometer-wide slump block. The roughly triangular piece of rim broke free when an asteroid impact excavated Plato crater. Its eastern edge stands up to 1.4 kilometers above the crater’s dark floor. Part of the floor is visible in the image just above right center, east of the long shadow of the rim. [emphasis mine]
That block is thus 14.5 miles wide, and almost a mile high. I am trying to imagine what it was like when it broke off the rim and fell eastward into the crater floor. I am having trouble doing so.
Below is a image of the entire crater, with the area of the image above indicated by a white box. It shows clearly how this crater splashed into the basalt lava plain of Mare Imbrium.
The asymmetrical pattern of debris surrounding the crater, mostly to the northeast, suggests the impact came from the southwest. The crater’s smooth floor also suggests that it caused the basalt in the mare to melt into a smooth pond of lava, which then solidified. The pit and rill to the west of the rim could have formed from lava drainage out of the crater and down into Mare Imbrium, though this is only a theory.
If you go to the link above, you can zoom into this image close enough to see individual boulders only tens of feet across.
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.
“That block is thus 14.5 miles wide, and almost a mile high. I am trying to imagine what it was like when it broke off the rim and fell eastward into the crater floor.”
That it happened silently makes it more difficult to imagine.
I wonder if this impact caused a high enough wind to fly a flag like it did the day Neil Armstrong was there. (We all know it wss a movie, right?)