Curiosity continues glitchy path to Mars mountain
Reference by: OiiO Space
April 23, 2016   12:11 AM

Sharp-eyed readers will notice the name of this column has changed from Curiosity Watch to Mars Watch. Let me explain why.

For the past few years the column has focused on the activities of the Mars rover Curiosity. Because much of its current activities are routine day-to-day — I should say sol-to-sol — tasks of a field geologist, I am now broadening the column to cover activities of all the spacecraft at Mars — in orbit and on the surface.

We will still keep a close watch on Curiosity, but we will also keep watch on what the other Mars spacecraft are doing and discovering

First, what has Curiosity been doing recently? 

During the past two months, the rover has made its way around the northern edge of a couple of sand dunes. It will soon turn south and pass by the Murray Buttes. This southward turn will take the rover across the Bagnold dune field, which has blocked Curiosity’s path to the higher parts of Mount Sharp since it first landed.

The current westward travel has crossed a high-standing section of ridgy rock called Naukluft Plateau.

On the top of this plateau, the wind has carved the rocks into dramatic shapes. Driving over the rough terrain has been extremely difficult. To add to this difficulty, the rover has been fighting a recurring short in its power generator and has also lost some sols due to problems at the Deep Space Network.

Curiosity is powered by a radioisotope thermoelectric generator. The short in this unit is not a new problem; it first occurred in November 2013. It has occurred a few times since then, but not often enough to be disruptive, just annoying. 

This short presents no hazard to the rover, but some of its operations, such as wheel steering, self check for unusual power behavior before starting. On April 3, 5, and 7, the short detection caused the rover to not execute the planned drive. Curiosity lost an entire week of activity. 

This problem has now been elevated from an intermittent annoyance to a real nuisance. Engineers are working on a solution.

The Deep Space Network, a system of large antennas on Earth, relays data between Mars and Earth. On March 24 a failure at the DSN prevented the rover team from receiving the images from the previous sol. 

This meant the team did not know the status after the drive, so it could not plan another drive or do any contact science. It could, however, perform untargeted remote sensing, so the sol was not a complete loss. 

On April 8 there was another DSN problem. This time it failed to uplink the rover’s command sequence. This equence was for two sols, so the contact science for both Mars days was lost. The DSN problems have yet to be resolved.

The difficult crossing is nearly complete. In the very near future, Curiosity will be off the Naukluft plateau and onto Murray rocks.