Inside Opportunity: Dust devils, high-altitude clouds, and sulfur-rich soils
Since my last update, Opportunity has traveled 100 meters westward up a slope in Marathon Valley to continue our search for the elusive phyllosilicates (clay minerals) that were detected from orbit by the Compact Reconnaissance Imaging Spectrometers for Mars (CRISM) instrument aboard the Mars Reconnaissance Orbiter (MRO).
The colorful soil area at Knudsen Ridge that I described back in my late March report turned out to be on slopes (greater than 32°) that were just too steep for our rover to successfully operate on, so we reluctantly backed down and moved on in search of more favorable slopes for our investigations.
Some interesting atmospheric phenomena highlighted Opportunity’s journey up Marathon Valley, which is located on the western rim of Endeavour Crater. Along our roving, I alerted our team to a couple of rare dust devils (dust laden whirlwinds) on sols 4311 and 4332.
The most spectacular dust devil was captured by our Navcam at 2:08 p.m. local true solar time on sol 4332. At the time, we were looking northeast on the floor of Endeavour Crater (Figure 1).
You may recall that the Spirit rover imaged numerous dust devils in Gusev Crater. However, dust devils in Meridiani Planum – the region where Opportunity is exploring – are very sparse. Dust devils tend to occur in the mid to late afternoon hours on Mars as the atmosphere heats up.
We also captured some high-altitude clouds made of ice crystals on sol 4336 at 3:03 p.m. local true solar time. On sol 4377, we directed Opportunity to do a wheel scuff across a fracture zone in a scientifically interesting region in order to expose subsurface materials with the hope that it may resemble what we saw previously on the high unobtainable slopes of Knudsen Ridge.
Our efforts proved worthy, and we have now found a region very high in sulfur, which indicates that this area had been altered by water in the past. We are continuing our investigations here and will, most likely, extend into early next week before we move on.
After we complete our soil experiments here, we will then drive to the south for several meters to examine another site. From this site, we will also image with the Pancam an unusual lobate feature that I first found in the sol 4345 Rear Hazcam (Figure 2).
Like many of you, I have been looking at Mars in the night sky these past few weeks. When doing so, I have also been looking at images of individual rocks and soil patches from Opportunity while staring up at the Red Planet for some spectacular perspective, which generates some thought-provoking and thankful moments for me personally.
I think it is very interesting to note that on today, June 2, we are celebrating the 50th anniversary of the first U.S. soft landing on the surface of the Moon. Surveyor 1 landed on a flat area inside a 62 mile wide (100 kilometers) crater north of Flamsteed Crater in the southwest corner of the Ocean of Storms at 1:17 a.m. EDT on June 2, 1966, after a flight lasting some 63 hours and 30 minutes.
This event was the first landing upon legs ever to happen on another celestial body and proved that the subsequent Apollo manned missions could safely touch down on the lunar surface. Four months earlier, the USSR had soft-landed the Luna 9 probe by bouncing and rolling across the surface of the Moon’s Ocean of Storms.
In perhaps a portent of what was to come for U.S. planetary surface mission lengths, Surveyor 1 lasted until January 7, 1967. Later this summer, on July 20, we will celebrate the 40th anniversary of the first landing on Mars by Viking 1 in Chryse Planitia, and then later, on September 3, the Viking 2 landing in Utopia Planitia.
This article is based on the views of the author and does not, necessarily, reflect those of SpaceFlight Insider
Dr. Jim W. Rice, Jr., is an Astrogeologist at the Planetary Science Institute, he has over 25 years research experience specializing on the surface geology and history of water on Mars. Dr. Rice is currently a Co-Investigator and Geology Team Leader on the Mars Exploration Rover Project (Spirit and Opportunity). Rice also has extensive mission experience as Associate Project Scientist on the Lunar Reconnaissance Orbiter and Mars Odyssey Orbiter Projects. He has been involved in Mars landing site selection and certification activities for every NASA Mars Mission since Mars Pathfinder. His career includes working for NASA, Astrogeology Headquarters of the United States Geological Survey, the Mars Spaceflight Facility located at Arizona State University and the Lunar and Planetary Laboratory located at the University of Arizona.