Perseverance’s first sample grab fails
Click for full image.
The first attempt by the Mars rover Perseverance to obtain a core sample has apparently failed.
The failure does not appear to be technical. All the hardware appears to have worked. When they inspected the interior of the hollow core drill however no sample was seen inside.
“The sampling process is autonomous from beginning to end,” said Jessica Samuels, the surface mission manager for Perseverance at NASA’s Jet Propulsion Laboratory in Southern California. “One of the steps that occurs after placing a probe into the collection tube is to measure the volume of the sample. The probe did not encounter the expected resistance that would be there if a sample were inside the tube.”
…”The initial thinking is that the empty tube is more likely a result of the rock target not reacting the way we expected during coring, and less likely a hardware issue with the Sampling and Caching System,” said Jennifer Trosper, project manager for Perseverance at JPL. “Over the next few days, the team will be spending more time analyzing the data we have, and also acquiring some additional diagnostic data to support understanding the root cause for the empty tube.” [emphasis mine]
Do the highlighted words remind you of anything? They do for me. The first thing I thought of when I read this was the drilling mole for InSight’s heat sensor. It failed in its effort to drill into the Martian surface because the nature of the Martian soil was different than expected. It was too structurally weak, and would break up into soft dust rather than hold together to hold the mole in place.
In the case of Perseverance, it appears right now (though this is not confirmed) that the drill successfully drilled into the ground, with its core filling with material, but when the core was retracted, that material simply fell out, as if it was too structurally weak to maintain itself inside the core.
The photo above of the drill hole and its thick pile of dust appears to support this hypothesis. Even though they drilled into what looked like bedrock the act of drilling fragmented that bedrock apart.
I am speculating based on limited information, so I am likely wrong. For example, the drill certainly has sensors to detect the density and structural strength of the rock it is drilling into. The engineers will check those numbers during drilling. If the rock doesn’t appear dense enough or structurally strong enough for a core sample, I would expect them to pick a different spot.
If true however it means that obtaining core samples at many locations in Jezero Crater will simply not be possible. This does not mean no samples will be obtained, because there are definitely places on Mars where the ground’s structure is solid enough for this method to work. Curiosity definitely found this to be true, when if found several places on Vera Rubin Ridge where its drill didn’t have the strength to penetrate the rock.
Readers!
My annual February birthday fund-raising drive for Behind the Black is now over. Thank you to everyone who donated or subscribed. While not a record-setter, the donations were more than sufficient and slightly above average.
As I have said many times before, I can’t express what it means to me to get such support, especially as no one is required to pay anything to read my work. Thank you all again!
For those readers who like my work here at Behind the Black and haven't contributed so far, please consider donating or subscribing. 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.
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Click for full image.
The first attempt by the Mars rover Perseverance to obtain a core sample has apparently failed.
The failure does not appear to be technical. All the hardware appears to have worked. When they inspected the interior of the hollow core drill however no sample was seen inside.
“The sampling process is autonomous from beginning to end,” said Jessica Samuels, the surface mission manager for Perseverance at NASA’s Jet Propulsion Laboratory in Southern California. “One of the steps that occurs after placing a probe into the collection tube is to measure the volume of the sample. The probe did not encounter the expected resistance that would be there if a sample were inside the tube.”
…”The initial thinking is that the empty tube is more likely a result of the rock target not reacting the way we expected during coring, and less likely a hardware issue with the Sampling and Caching System,” said Jennifer Trosper, project manager for Perseverance at JPL. “Over the next few days, the team will be spending more time analyzing the data we have, and also acquiring some additional diagnostic data to support understanding the root cause for the empty tube.” [emphasis mine]
Do the highlighted words remind you of anything? They do for me. The first thing I thought of when I read this was the drilling mole for InSight’s heat sensor. It failed in its effort to drill into the Martian surface because the nature of the Martian soil was different than expected. It was too structurally weak, and would break up into soft dust rather than hold together to hold the mole in place.
In the case of Perseverance, it appears right now (though this is not confirmed) that the drill successfully drilled into the ground, with its core filling with material, but when the core was retracted, that material simply fell out, as if it was too structurally weak to maintain itself inside the core.
The photo above of the drill hole and its thick pile of dust appears to support this hypothesis. Even though they drilled into what looked like bedrock the act of drilling fragmented that bedrock apart.
I am speculating based on limited information, so I am likely wrong. For example, the drill certainly has sensors to detect the density and structural strength of the rock it is drilling into. The engineers will check those numbers during drilling. If the rock doesn’t appear dense enough or structurally strong enough for a core sample, I would expect them to pick a different spot.
If true however it means that obtaining core samples at many locations in Jezero Crater will simply not be possible. This does not mean no samples will be obtained, because there are definitely places on Mars where the ground’s structure is solid enough for this method to work. Curiosity definitely found this to be true, when if found several places on Vera Rubin Ridge where its drill didn’t have the strength to penetrate the rock.
Readers!
My annual February birthday fund-raising drive for Behind the Black is now over. Thank you to everyone who donated or subscribed. While not a record-setter, the donations were more than sufficient and slightly above average.
As I have said many times before, I can’t express what it means to me to get such support, especially as no one is required to pay anything to read my work. Thank you all again!
For those readers who like my work here at Behind the Black and haven't contributed so far, please consider donating or subscribing. 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.
I think your analysis makes nothing but sense Bob… Sandstones on earth can be very soft, and it seems ( unfortunatly ) more and more likely that at least some of the sedimentary sandstones of Mars are products of some sort.of dry process. Given that Mars only has a fraction of earth gravity it’s no surprise if it’s red sandstone turns out to be softer and fluffier than expected.
Here’s hoping that when Perseverance hits real water laid strata, this also means all the fossils will be eroded out, and easy to image, and stick in a sample tube!
If they new about this issue from past missions, why didn’t they anticipate it and do the drilling differently this time? Not enough lead time? Could they have put a “lid” on the bottom of the drill to “catch” the core sample before it fell out?
Kevin Smith: 1. The InSight mission was not a drilling mission. It was digging into the ground to bury a heat sensor. Do a search on Behind the Black for InSight. Lots of interesting stuff to learn.
2. They built Perseverance based on their experience with Curiosity, which has drilled into Gale Crater numerous times. However, grabbing a core sample was not something Curiosity ever did.
3. And yes, a “lid” makes sense, in hindsight. On Earth however such a thing is generally not needed when you gather a core sample.
Core drilling process…..
Black Diamond Drilling Services Australia
https://youtu.be/HjSX41ecm94
2:19
Operation of the Core Barrel
Black Diamond Drilling Services Australia
https://youtu.be/bS6iPJowZWc
3:36
The grain size of this “sand” stone would be quite a bit smaller.
The only way for erosion to work is by wind.Wind slams the grains together and wind leaves the material in protected places.
Low gravity and ‘morning dew'(microscopic amounts of water)are the only thing to hold this stuff together.
A small vacuum could have helped in this situation. And it could help in holding good core samples in the tube until they are dropped out.
pzatchok observed: “A small vacuum could have helped in this situation.”
True, but given that surface pressure on Mars is near-vacuum to start (from our perspective), it may have been cost-prohibitive to have the machinery to lower the pressure in a vessel further. Perhaps the pressure differential would not make a significant difference, given the expected mass of the sample. Lots of stuff going on here, which we get to see virtually real-time.
RockStrong™ Coring System –
Optimizing Coring Performance in Extreme Conditions
Halliburton 2014
https://youtu.be/U4szIK3yJcc
2:27