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James Rice
July 1, 2018
View of Opportunity Solar Panels in 2014 Image: NASA / JPL-Caltech / Cornell University / Univ.Arizona
Our Intrepid Opportunity rover is currently overcoming a huge global dust storm that began on May 30th. the storm has shifted south along the well-known Acidalia thunderstorm in Xanthe Terra. A few days later, the storm had spread from the east to Valles Marineris north of Arabia. It then moved across the equator and south towards Meridiani Planum where stands Opportunity
This storm is unusual in that it started so early in the spring season of the southern hemisphere. Dust storms usually start in the Martian summer. The only other dust event that occurred during this season is the one that occurred in 2001. In fact, this continuous dust storm is the oldest ever observed.
The last contact we had with our rover was on Sol 5111 (June 10, 2018), we now think that it is likely that Opportunity experienced a low-power flaw and did not only sleep to wake up when the sky will eventually disappear. We started listening Opportunity on the 5112 floor. I was the geology team leader for our last meeting before suspending our scientific operations. Our rover is perched on the slopes of the Perseverance Valley facing south and struggles to survive this dust storm. We decided to leave the robotic arm of Opportunity deployed on the rock target, La Joya.
There was no signal from Opportunity during any of the potential slots up to this point. A formal listening strategy is being developed for the coming months. It is now 20 days since we had our last contact of Opportunity . From our last status report Opportunity today (June 30th), this storm shows no signs of slowing down anytime soon. We were lucky enough to perform an uplink last night at the potential low power window. We sent a real-time beep as we did in the last two weeks. We had a negative detection of the beep at the scheduled time.
Advanced Green Opacity: This graph compares atmospheric opacity in different years of Mars from the perspective of NASA's used rover. . The green peak of 2018 (year March 34) shows how quickly the dust storm of Mars has cleared the sky. A previous dust storm in 2007 (red, year 28 of March) was slower to build
The vertical axis shows atmospheric opacity and the horizontal axis shows the Martian season, which is measured by where the sun is in the Martian sky compared to its apparent position on the March spring equinox. Photo Credit: NASA / JPL-Caltech / TAMU
One of the last scientific measurements that Opportunity collected was what we call a tau, which is a measure of optical depth, and informs us about the way there is a lot of dust in the atmosphere. This tau value was calculated at 10.8, the highest (the worst) ever recorded by a Mars surface mission. The previous record was Viking to 9. Opportunity survived a violent storm in June-July 2007. This recent storm is much more serious and our rover is 11 years older (Des Opportunities have appeared on the surface of the Red Planet since January 25, 2004.)
We went from 645 watt hours in good health on June 1 to an unprecedented depression, threatening life, about a week later. Our last power reading on June 10 was only 22 watt hours, the lowest ever seen . The main concern is that we will not have enough power to keep us warm enough to avoid any damage to the vehicle electronics. However, our thermal experts think we will stay above these low critical temperatures because we have a hot electronic box (WEB) that is well insulated. We do not expect any thermal damage to batteries or computer systems. Fortunately for us it is also the Martian spring and dust, while hindering our solar energy in the day, helps us keep warm at night.
The rumors about the death of Opportunity are very premature at this point and we are far from dead. It's a dark situation right now, without a doubt, and we still have a long way to go in our last challenge on the red planet. However, we have an impressive record of overcoming the challenges over the last 14 and a half years and our team is the best on both worlds.
The previous update was written by Jim Rice, co-investigator and geology team leader on the Mars Exploration Rover Project and reflects his experiences working on the program [19659007]
James Rice
Dr. Jim W. Rice, Jr., is an astrogeologist at Planetary Science Institute, he has more than 25 years of specialized research experience on surface geology and water history on Mars. Ms. Rice is currently a co-investigator and geology team leader for the Mars Exploration Rover (Spirit and Opportunity) project. Rice also has extensive mission experience as a Project Associate Scientist on the Lunar Reconnaissance Orbiter and Mars Odyssey Orbiter Projects. He has been involved in the selection and certification activities of the Mars landing site for each Mars Mars mission from NASA since Mars Pathfinder. During his career, he has worked for NASA, the United States Geological Survey's headquarters of astrogeology, the Arizona State University's Mars Spaceflight Facility, and the University Lunar and Planetary Laboratory. from Arizona.
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