[X] My Assistant

[Ant103]

Good Evening!

In looking images who show Grissom Hill on the horizon, I've asked me a question : "Is it possible for Spirit to roving to Grissom Hill?"
To make me sure, I went on Marsrovers JPL site and searched for an MGS satellite image showing the landing site.


I've calculated approximately the distance : 8 or 9 kms. It's far but this could be a very interesting place ... more than Columbia Hill!
Western from Grissom Hill, I'd seen a very big crater (1 or 2 kms diameter...). This one is certainly interesting for "areologist" who want to study the past of Gusev...

Spirit is in good health. Why not?

[edstrick]

"tidally driven"...

The martian atmosphere has thermally driven tides as the planet rotates underneath solar illumination. Dayside atmosphere expands, there are (at a simplest armwaving level) lateral winds toward the terminators at dawn and dusk, and the nightime atmosphere contracts. But it's more complex than that, as the atmosphere has natural periods of oscillation.

The Viking landers got a really good first look at these processes. They had a basic minimal meteorology set: Temperature, Pressure, Wind Speed and Direction. No humidity reading, though. They took 24 hour low data rate meteorology most of the time, and higher data rate sampling at various times for detailed boundry-layer meteorology studies.

Both landers saw pronounced highly repetitive pressure and wind-speed/direction variations on a cyclic daily basis as the atmosphere regularly "sloshed" back and forth under diurnal heating and cooling. There was more complex structure in the pressure and wind cycles due to semi-diurnal tides.. 2 cycles-per-day sloshing. These global tides combined with upslope daytime wind flows and downslope nightime flows at the Viking 1 site. Viking 2, further north (48 deg) saw strong patterns of cyclic cold front passages and/or the pressure/wind patterns of periodic low pressure regions passing by to the north.

During the 1977 double globe-encircling dust storms, the cold front pattern at VL2 changed dramatically, and the diurnal pressure/wind cycles at both landers changed in strength, phase, and relative strength of the diurnal and semi-diurnal components. Much of that reasonably well matched theoretical modeling of the atmosphere's thermal tide responses during varying dust loadings.