Mars Perseverance is about to collect and cache the first Martian rock sample for its eventual return to Earth via the Mars Sample Return mission a decade from now. The Martian samples will be analyzed by instruments on Earth that are too large to be sent to Mars and will be available for future generations of scientists to analyze using tools and techniques that we had not thought of until now.
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What I hadn’t realized before is how long it takes to collect samples after the time spent looking for particularly interesting rocks to excavate. That time we spend finding the right rock to excavate takes time, of course, because we only have 38 sample capsules for the main mission and any mission extensions, so we have to be very selective about which samples to collect. From 17 to 20 samples will be collected in the main two-year mission, with the remainder being collected in the projected extensions of the mission.
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There was already a multi-year process of careful mapping of orbit and positioning to search for suitable rocks before perseverance reached Mars. Suitable rocks are those that react with water, contain organic molecules, and are the kind that can maintain the chemical traces of life for billions of years.
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Once the intense debate settles over which particular rock to sample and at what point to drill into the rock, there is an 11-day drilling and buffering process.
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After receiving instructions from Earth millions of miles away, Perseverance will carefully place the toolbox and strike the rock with the end of his robotic arm in a carefully designed set of movements.
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You will spend the first days analyzing a portion of the rock next to the proposed drilling site using the instruments at the end of the robotic arm, as well as a laser spectrometer and an ultra-high-resolution camera at the head of the mast. They will obtain valuable data on the rock that they will take samples by analyzing its geological twin.
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After all that detailed study, the rover will rest for a day and then start digging. The robotic hammer drill will penetrate about 2 inches, separate the sample from the rock core, transfer the sample to the drill carousel, and then transfer it to the adaptive reel assembly, where it will be measured, photographed, plugged, and hermetically sealed. Ultra-sterilized tube about the size of a pinkie, then place on a storage rack.
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Once enough samples have been stored, Perseverance will deposit the sample collection on Mars for later retrieval by a sample return mission. Each cache in each repository will include so-called “witness blanks” and “procedural blanks” that will be displayed after potential contamination events to provide reference points for calibration.
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I remain in awe of the painstaking and meticulous care that various work teams take in developing, testing, and retesting hardware and software as they attempt to consider each potential failure or environmental emergency.
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Teams on the Mars Insight rover using a seismometer to examine the interior of Mars held a press conference to announce their findings, published in a series of peer-reviewed articles. The crust is only 20 to 24 miles thick, a surprising result because we expected it to be much thicker than Earth’s continental crust, which is 22 to 43 miles thick.
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On the other hand, the mantle layer is thicker than expected, stretching 250 to 370 miles, and is relatively deeper than Earth’s mantle, and the mantle of Mars does not contain the two sub-layers that Earth has. This means that Mars can lose heat from its core more easily. The core of Mars is still liquid and larger than originally thought. Rather than just being a nickel-iron like Earth’s core, the core of Mars also contains relatively lighter elements like sulfur, oxygen, and mixed carbon compounds, so it’s less dense and likely doesn’t have a solid inner core. like the Earth. . The temperature difference between the center of the core and the top of the core is not large enough to create the massive convection currents necessary to create a global magnetic field that would protect the Martian atmosphere from being disrupted by the solar wind.
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In exoplanet news, ALMA, Chile’s large radio observatory, captured the first image of a dust-covered planetary disk surrounding a forming planet. The Jupiter-sized planet is in the PDS 70 system, about 400 light-years away. The disk is likely to eventually form moons, so the system will provide a good laboratory to test our ideas about how moons form, just as the many disks ALMA has photographed around young stars help us understand how they form. the planets.
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Eye to heaven for the Perseids
Speaking of dust: Earth began to move through the trail of dust left by Comet Swift-Tuttle to create the Perseid meteor shower. We will reach the densest part of the creek on the night of August 11-12 and we will have a thin crescent moon that will set early. There is no moon that blurs the view. Let’s hope the sky is smoke-free!
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![[FCM-MHSC] Midi Libre criticizes the finish](https://www.allezpaillade.com/wp-content/uploads/2020/11/midilibre-2.jpg "[FCM-MHSC] Midi Libre criticizes the finish")