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Originally Posted by SuperDanman
My question is does anyone (*glance at Dave Lavery*) know why its taking a week for the rover to roll off the platform?
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Immediate, smart-alecky, knee-jerk, wise-a** response: "hey, you think it is so easy operating a stupid rover in the middle of a planet-wide sand storm from 300 bazillion miles away with a communications pipe just slightly better than two cups and some string, then let's just see YOU do it!"
Okay, now that I have that out of my system, here is the real answer: it was always planned to take at least 10 sols (martian days) to have the rover drive off the lander. During that period, it has to unstow all the solar arrays, raise the PanCam Mast Assembly (PMA - where the main cameras are located), deploy the high-gain antenna, unstow the Instrument Deployment Device (IDD - the instrument "arm"), stand the rover up, deploy all the wheel assemblies, sever three different cable bundles connected to the lander, deploy and retract the Rover Lifting Device multiple times, etc., etc., etc. Those are just some of the mechanical operations associated with getting the rover ready. For many of these steps, we have to stop and check back on Earth to make sure they have completed properly before proceeding to the next step. Each of these validation checks can take several communication cycles, and may cover a full day or more.
In addition, we have to photograph and transmit the complete panorama of the area around the rover, and take several other science measurements and get the data back to Earth. All this has to be done so that we can understand the context of the region in which we have landed, and make an intelligent decision about the safest way to egress the lander and in which direction we want to travel once we are on the ground.
Just as an example, just photographing the full panorama at the full resolution of the camera system can take up to four sols (a full panorama is about 5000 x 25000 pixels, in stereo, with 14 different wavelength filters, resulting in an image that is over 2.6GB). Getting that data down to Earth from the spacecraft can take several more days, depending on the other activities running in parallel. Although we have a relatively high data rate for the communications system (up to a whopping 112Kbps - about twice the throughput of a dial-up modem), the full data rate is available only during a few short windows each day. So getting the data sets back to Earth is a lengthy process.
Yes, there have been some issues with the airbags at the front of the lander potentially getting in the way. But realistically, they have impacted the egress timeline by only a small fraction. It really just comes down to this: we have a $410,000,000 asset sitting on another planet. We are going to be extremely cautious about getting it past this last high-risk manouver. Believe me, after all the work that has gone into it, no one wants to get all six wheels on Mars soil more than we do. But we are going to take our time and make sure it is done right, and not impose any additional risk by rushing the process.
-dave