So, where does Mastcam-Z come into this story? There was a process defined before the rover landed to investigate the behavior of dust devils. First, survey: identify when and where dust devils could be seen. Second, take Navcam time-lapse video over wide angles to better characterize where to see dust devils and how they move and evolve—much like the Spirit and Curiosity time-lapse sets.
The rotation rate gives wind speeds, when coupled with a distance estimate. The upward transport of dust is a key parameter in knowing how much dust is being put into the atmosphere by dust devils—we need to know how common they are, how big they are, how much dust they pick up, and how fast that dust moves upward. Mars had other plans. Dust devils showed up before dust devils surveys were used. The Navcam dust devil movies have not been tried yet. We certainly were not ready to try to target a dust devil video.
However, on sols 31 and 33 Mastcam-Z was used in video mode at about 7 frames per second to test the process of taking a long video and getting the data down. This was done, not for dust devils, but for preparations for eventual video of the Ingenuity helicopter in flight even before Ingenuity deployed to the surface. And guess what showed up in the test? A dust devil can be seen moving through the field of view about 60 seconds into the about 7-minute video on sol 31 above.
It was dusty enough to be spotted by a team member in the raw images, but not dusty enough to see clear detail.
This is where the motion filtering helps. Typical diameters of dust devils range from 10 to feet, with an average height of approximately to feet. In most locations, dust devils typically last only a few minutes before dissipating. Although, in deserts typical of northern Arizona, dust devils can reach heights of several thousand feet and last on the order of an hour or more. Wind speeds in larger dust devils can reach 60 mph or greater.
Even though they are generally smaller than tornadoes, dust devils can still be destructive as they lift dust and other debris into the air. Small structures can be damaged, and even destroyed, if in the path of a strong dust devil. Dust devils form in areas of strong surface heating, usually at the interface between different surface types, such as asphalt and dirt, or even irrigated fields and dirt roads.
Typically, they occur under clear skies and light winds, when the ground can warm the air to temperatures well above the temperatures just above the ground. This is a very unstable condition, since the heated air is less dense and lighter than the cooler air above it.
If the temperature of the ground becomes much warmer than the air above it, vertical mixing will take place to release this unstable configuration. Once the ground heats up enough, a localized pocket of air will quickly rise through the cooler air above it.
The sudden uprush of hot air causes air to speed horizontally inward to the bottom of the newly-forming vortex. This rapidly rising pocket of air may begin to rotate, and if it continues to be stretched in the vertical direction, will increase in rotation speed. Fall Flash Sale. Get smart. Sign up for our email newsletter. Sign Up. Support science journalism. Knowledge awaits. See Subscription Options Already a subscriber?
See Answer. Best Answer. Study guides. Q: How powerful can a dust devil get? Write your answer Related questions. What is another name for a dust devil? How do say 'dust devil' in spanish? Is a dust devil a tornado? What color is a dust devil? What is a whirlwind that spins up from bare soil? When was Dust Devil - Madness song - created? Ghostly dust devil?
Can you ride a dust devil? Can people go inside of a dust devil tornado? Can you walk through a dust devil? What actors and actresses appeared in Dust Devil - ?
Why does taz spin? Are dust devils harmful? Is Devil Jin weak?
0コメント