NASA’s Perseverance rover is traversing the Martian landscape with an enhanced autonomous navigation system. The rover has returned more than 107,000 raw images that are loaded in the publicly available mission multimedia catalog. This is the first phase of the rover’s epic journey across the Jezero Crater floor looking for clues of possible ancient life. The rover team at NASA’s Jet Propulsion Laboratory works around the clock planning driving routes and transmitting instructions. The team uses 3-D virtual reality glasses as an aid to visualize routes around obstacles.
Over time, Perseverance will become more autonomous using enhanced AutoNav. This system uses multiple cameras to plan a route avoiding obstacles without more time-consuming direction from controllers back on Earth.
“The rover is thinking about the autonomous drive while its wheels are turning,” said Vandi Verma, a senior engineer and rover controller at JPL.
Perseverance can drive at a top speed of 393 feet per hour. That’s about six times as fast as the Curiosity rover operating on an earlier version of AutoNav.
A Big Leap for Ingenuity
The Ingenuity UAV helicopter is now the rover’s exploration companion. Ingenuity is returning 3-D images of possible routes and objectives ahead of the rover. Ingenuity had a planned service life of five flights. Continued flight success, endurance and complexity have encouraged NASA and JPL to extend Ingenuity’s mission with more ambitious flights. The expectation is to fly Ingenuity about once every two weeks.
The eighth flight of Ingenuity was on June 21 (Sol 119). JPL reported that the flight lasted 77.4 seconds, flew 525 feet and landed about 440 feet from Perseverance rover.
Ingenuity’s ninth flight was on July 5 (Sol 133). The helicopter flew 2,041 feet in 167 seconds. Its speed was about 16 feet per second. Ingenuity took color images with its 13-MP camera relayed to Earth by Perseverance. The flight was the first aerial look-ahead for the rover.
Ingenuity flew around contacts of Séítah terrane and adjacent areas.
“This was a big leap – big leap – in terms of what we’ve done before. We went between sites that were 625 meters apart, which is enormous compared to what we’ve done before,” Ingenuity chief pilot Harvard Grip said in an interview. The images will help the JPL team decide whether and where to send Perseverance to drill rock samples in the Séítah contact region.
“Using a technique we developed that helps us find rare, hard-to-detect mineral phases in data taken from orbiting spacecraft, we found two outcrops of hydrated silica within Jezero crater,” said planetary scientist Jesse Tarnas at Brown University as Perseverance kicked off the science phase of its mission. “We know from Earth that this mineral phase is exceptional at preserving microfossils and other biosignatures, so that makes these outcrops exciting targets for the rover to explore.”
On Earth, opal is a form of hydrated silica.
In this first science phase, Perseverance will navigate to a low-lying area where the rover can survey some of the oldest geologic features in Jezero Crater. This will be a good test of the rover’s AutoNav and sampling systems.
“The material that forms the bottom layer of a delta is sometimes the most productive in terms of preserving biosignatures. So, if you can find that bottomset layer and that layer has a lot of silica in it, that’s a double bonus,” said Brown planetary scientist Jack Mustard.
Two Geologic Units of the First Science Mission
This first science mission, to the south of the Octavia Butler landing site, will last at least a hundred sols. The rover will explore two of Jezero’s deepest and oldest geologic units. The first unit, “Crater Floor Fractured Rough,” is the floor of Jezero interpreted to be mafic and olivine bearing from orbital remote sensing according to JPL’s Katie Stack Morgan (see the December 2020 EXPLORER for more details). The adjacent Séítah unit (amid the sand in Navajo) has sand dunes, bedrock, ridges and layered rocks.
“Starting with the ‘Crater Floor Fractured Rough’ and Séítah geologic units allows us to start our exploration of Jezero at the very beginning. This area was under at least 100 meters of water 3.8 billion years ago. We don’t know what stories the rocks and layered outcrops will tell us, but we’re excited to get started,” said JPL’s Kevin Hand.
The first science mission will conclude when Perseverance returns to the Octavia Butler landing site. The rover will have traveled between 1.6 and 3.1 miles and up to eight of 43 sample tubes will be filled with Mars geologic samples. At some point, the sample tubes will be cached on the surface for return to Earth on a future mission. Besides pure science value, the sample will be immediately processed on Earth to determine hazards for future human Mars landings.
Perseverance’s second science mission will traverse north then west into Jezero’s delta region. The delta is an unmistakable feature visible from orbital remote sensing and from the rover’s vantage point. It formed where an ancient river channel filled a lake within Jezero Crater 3.5 billion years ago. The delta might contain layered carbonates similar to those on Earth, which might preserve fossilized ancient life and traces of ancient biological processes.
After testing and calibrating the rover’s instruments, team scientists have determined that several of the rocks are chemically similar to volcanic rocks on Earth. Some have been eroded by wind and water. They won’t say much more until findings are published at upcoming geology science conferences – probably by the end of the year.
Kirsten Siebach of Rice University and the Perseverance Science and Operations Team, who participated in the AAPG Perseverance Watch Party in April, will be a keynote speaker detailing Perseverance progress at the AAPG/Society of Exploration Geophysicists’ 2021 International Meeting for Applied Geoscience and Energy, or IMAGE ’21, which is scheduled for Sept. 26-Oct. 1, in Denver.
Katie Stack Morgan, JPL deputy project scientist for the Perseverance rover, will provide an update about the mission’s current work exploring the Martian surface during the 24th Annual International Mars Society Convention, scheduled for Oct. 14-17, 2021.
Meanwhile, Paul Byrne, a North Carolina State University planetary scientist remarked, “Something that I find hard to remember in looking at these images of Jezero Crater by Perseverance is just how cold it is. Sure, the sky is orangey and the light has a warm hue, but on Sunday July 4, the local high there was -24 degrees Celsius (-11 degree Fahrenheit) and the low was -82 Celsius (-180 Fahrenheit). That’s d--- cold!”
Stay tuned while Perseverance and Ingenuity travel south to explore Jezero crater together. Soon Perseverance will drill its first samples to be archived for future return to Earth labs.
If AAPG EXPLORER readers were asked whether or not they would want to travel to Mars to do geology on the Red Planet, we would have two camps. One camp would enthusiastically say, “Yes! Sign me up!” The other would say, “No thanks! I love the Earth and I’ll stay here!” With the tireless Curiosity and Perseverance rovers and Ingenuity helicopter, we can vicariously explore Mars in high-definition color in this AAPG EXPLORER section.