Curiosity continues to explode the breadth and depth of human knowledge of the Red Planet. The latest comes from measurements that describe a planetary atmospheric tide that has the spherical fourth planet revolving within an egg shaped body of atmospheric gasses. Here is how NASA describes it.
This diagram illustrates Mars' "thermal tides," a weather phenomenon responsible for large, daily variations in pressure at the Martian surface. Sunlight heats the surface and atmosphere on the day side of the planet, causing air to expand upwards. At higher levels in the atmosphere, this bulge of air then expands outward, to the sides, in order to equalize the pressure around it, as shown by the red arrows. Air flows out of the bulge, lowering the pressure of air felt at the surface below the bulge. The result is a deeper atmosphere, but one that is less dense and has a lower pressure at the surface, than that on the night side of the planet. As Mars rotates beneath the sun, this bulge moves across the planet each day, from east to west. A fixed observer, such as NASA's Curiosity rover, measures a decrease in pressure during the day, followed by an increase in pressure at night. The precise timing of the increase and decrease are affected by the time it takes the atmosphere to respond to the sunlight, as well as a number of other factors including the shape of the planet's surface and the amount of dust in the atmosphere.This is scientifically predictable, of course, but it is another thing to have actually made the scientific measurements to describe the findings.
I harbor the conviction that it is impossible to learn too much about the most Earth-like, seemingly, of the inner, rocky children of Sol. The Curiosity Rover and the Mars Science Laboratory that it carries are not even finished with the initial shakedown and testing of the instruments, but NASA has already made the unprecedented discovery of flowing water on ancient Mars.
Now, the tests are almost complete. What remains is to use the impact drill. Curiosity is now going to look for a really good rock to drill. This is the final stage of what Curiosity and its instruments are capable of doing and it is a big step forward.
Our American hero super-scientists and engineers are going to eventually tell us a fascinating story about the ancient, watery past of Gale Crater and Mount Sharp. Prepare to be dazzled.
For all of my Mars diaries and all things Mars on Daily Kos go to Kossacks on Mars.