The scattered debris from Perseverance’s landing, now being tracked by the rover
Click for full image.
Click for full image.
The Perseverance science team today posted a detailed update on the various pieces of debris that both the rover and the Ingenuity helicopter have been tracking since both landed on Mars in February 2021.
Some of the EDL [entry, descent, landing] hardware broke into smaller pieces when it impacted the surface. These pieces of EDL debris have been spotted in images of the Hogwallow Flats region, a location roughly 2 km to the northwest of the EDL hardware crash zones. As of Sol 508 (July 24, 2022), the operations team has catalogued roughly half a dozen pieces of suspected EDL debris in this area. Some of these EDL debris are actively blowing around in the wind. So far, we’ve seen shiny pieces of thermal blanket material, Dacron netting material that is also used in thermal blankets, and a stringlike material that we conclude to be a likely piece of shredded Dacron netting.
To the right are two of the most interesting examples. The top image shows the parachute and associated equipment from the landing, taken by Ingenuity during a flight in April 2022. That image, when compared with an earlier picture taken from orbit, showed that the wind of Mars, though incredibly weak, had been able to shift the parachutes edges.
The second image shows the string that the rover photographed on July 12, 2022, and had blown away four days later when Perseverance re-photographed this site.
Today’s update notes that the area in the crater they have dubbed Hogwallow Flats “appears to be a natural collecting point for windblown EDL debris.” The flats are an area at the foot of the delta that flowed into Jezero Crater in the past, and is an area where Perseverance has been traveling most recently.
That the wind has been able to move small pieces so effectively is I think somewhat of a surprise. That it is gathering the material against the crater’s western cliffs suggests the prevailing winds here blow to the west.
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 full image.
Click for full image.
The Perseverance science team today posted a detailed update on the various pieces of debris that both the rover and the Ingenuity helicopter have been tracking since both landed on Mars in February 2021.
Some of the EDL [entry, descent, landing] hardware broke into smaller pieces when it impacted the surface. These pieces of EDL debris have been spotted in images of the Hogwallow Flats region, a location roughly 2 km to the northwest of the EDL hardware crash zones. As of Sol 508 (July 24, 2022), the operations team has catalogued roughly half a dozen pieces of suspected EDL debris in this area. Some of these EDL debris are actively blowing around in the wind. So far, we’ve seen shiny pieces of thermal blanket material, Dacron netting material that is also used in thermal blankets, and a stringlike material that we conclude to be a likely piece of shredded Dacron netting.
To the right are two of the most interesting examples. The top image shows the parachute and associated equipment from the landing, taken by Ingenuity during a flight in April 2022. That image, when compared with an earlier picture taken from orbit, showed that the wind of Mars, though incredibly weak, had been able to shift the parachutes edges.
The second image shows the string that the rover photographed on July 12, 2022, and had blown away four days later when Perseverance re-photographed this site.
Today’s update notes that the area in the crater they have dubbed Hogwallow Flats “appears to be a natural collecting point for windblown EDL debris.” The flats are an area at the foot of the delta that flowed into Jezero Crater in the past, and is an area where Perseverance has been traveling most recently.
That the wind has been able to move small pieces so effectively is I think somewhat of a surprise. That it is gathering the material against the crater’s western cliffs suggests the prevailing winds here blow to the west.
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
Wonder when the Green New Deal will hit Mars
“That the wind has been able to move small pieces so effectively is I think somewhat of a surprise.” If I recall correctly, since the Martian atmosphere is so much less dense than Earth’s, a wind of a certain velocity has less force than an Earthly wind does.
Robert wrote: “Today’s update notes that the area in the crater they have dubbed Hogwallow Flats ‘appears to be a natural collecting point for windblown EDL debris.’ The flats are an area at the foot of the delta that flowed into Jezero Crater in the past, and is an area where Perseverance has been traveling most recently.”
This could be true, especially since there were not many reports of debris sightings in the earlier exploration south of this area. However, this could be due to a slow migration of this debris. Two of the pictures show that the debris moves slowly. The debris could be spreading in all directions but has only recently caught up with the rover. Slow migration could explain why debris was not found in the first — early — locations explored.
There is also the problem of observation bias. The rover only sees what is around it, and if debris is blowing in all directions then we could falsely believe that it is only or mostly blowing in the direction of the rover.
Another factor could be wind velocity, which may have been slower in the past and could not move as much as fast. Debris may only now be arriving at locations that Perseverance previously explored and may have been missed because it had not yet arrived. (This is different than my first alternate explanation, above, in that this explanation has a change in wind speed. Otherwise it is the same thing.) If Perseverance has a wind gauge, and who wouldn’t want a weather station mounted to his Martian rover, then the answer of wind velocity and direction is stored somewhere.
One thing that we can be sure about: we seem to have polluted Mars more than we previously believed.