Each frame corresponds to a tau value, or measure of opacity: 1, 3, 5, 7, 9, 11.
NASA's Opportunity rover on Mars did not return a call from Earth Tuesday (June 12) while enduring a massive dust storm that scientists have called "one of the most intense ever observed". "And we're concerned about it, obviously. We are listening every day for possible signals from the rover", he said, likening the atmosphere among colleagues to having a loved one lying in a coma. "And so we are".
There is no chance of Opportunity being buried or getting a wheel stuck in dust. Several days have passed and the storm still rages on.
In the meantime, Opportunity's science operations remain suspended and the Opportunity team has requested additional communications coverage from NASA's Deep Space Network - the global system of antennas that communicates with all of the agency's deep space missions. Opportunity has lasted more than 50 times longer than its original 90-day mission plan, NASA officials have said.
Last night Nasa detailed how a real example of such a enormous natural event left their solar-powered rover Opportunity uncontactable and in danger. By now, two weeks later, the dust storm is nearly completely blotting out the Sun! As such, NASA says it now believes Opportunity has put itself into a "low power fault mode", which means that only its mission clock remains active; all subsystems are currently powered down.
Artist's concept of the Opportunity rover on Mars.
If the power level drops below that point, however, the rover will lose the services of its clock.
But without the clock, Opportunity would not know what time it is. The stranded rover houses eight radioisotope heater units packed with plutonium, which generate about eight watts of heat.
"We think we can ride this out for a while".
Astronauts living on Mars, for instance, would not want to get caught outside in a fierce dust storm. "We're also going into the summer season, and so the rover will not get as cold as it would normally. When the skies clear and the rover begins to power up, it should begin to communicate with us", Callas said, expressing confidence that Opportunity will not be buried in dust.
Opportunity and its twin rover, Spirit, which arrived the same month, both carrying a suite of scientific instruments to study the terrain, operated on opposite sides of the planet. They landed in 2004. At this rate, it could have many more years of life left in it!
Spirit has not worked for several years, but Opportunity has kept exploring well past its expected mission lifetime.
But the current dust storm is a definite challenge.
Officials said Wednesday they're hopeful the rover will survive the storm, which already covers one-quarter of Mars and is expected to encircle the planet in another few days.
Scientists said the swirling dust has created an extreme smog that blots out sunlight.
People working with the rover have also become attached to it over the years, so even if things are looking okay, it's still a scary prospect that this rover is alone and unable to phone home on Mars.