Phobos Options

[mcaplinger]

Put another way - the ExoMars rover is going to be more expensive now than when it's actually operating.

Well, likely true, but this can depend on how the mission plays out. If they just cancelled it outright it wouldn't cost "anything" (except substantial runout costs, I suspect.) And they could put it into some form of deep hibernation and it might not cost as much as delayed missions under active development would cost for the same period, though this is rarely done (DSCOVR is sort of an example.) Of course, if they end up flying it, it will cost far more than it would have when Russia was involved.

Bottom line for MEx; despite statements to the contrary, active missions are rarely cancelled if they are still at all productive. The larger worry for MEx is that the spacecraft is low on fuel, but this seems to have been mitigated to a larger degree than was thought previously (I'm assuming that's just not excessive optimism on someone's part.)

[cndwrld]

Bottom line for MEx; despite statements to the contrary, active missions are rarely cancelled if they are still at all productive. The larger worry for MEx is that the spacecraft is low on fuel, but this seems to have been mitigated to a larger degree than was thought previously (I'm assuming that's just not excessive optimism on someone's part.)

For MEX, the fuel might be a problem if we go into a few safe modes for some reason. But there hasn't been one for a long time.

Right now, one of the biggest potential issues is loss of the gyros. The laser diodes in the gyros are degrading with time, at different rates. At the European Spaceflight Operations Centre (ESOC) in Darmstadt, Germany, the flight control team is amazing. They've found ways to reduce use of the gyros significantly. But they won't last forever.

[bobik]

Funny how time flies (When you're having fun)

On Friday 21 July at around 05:04:47 UTC, Mars Express (MEX) will make a close flyby of Phobos at a distance to the surface of just 48.4 km, according to the latest MEX SPICE Kernel Dataset (SKD), via WebGeocalc (WGC).

My clumsy freehand overlay of a WGC-generated Nadir Ground-track plot on a colour-coded topographic map of Phobos seems to be in good agreement with the corresponding Sub-point radius vs. Time plot. The blue arrow shows the flight direction, the two concentric circles mark the point of closest approach to the surface, the small dots on the plot are one second apart, and the length of the plot between start at 05:03:42.465 and end at around 05:05:54.924 UTC is the time period when the distance between MEX and the centre of Phobos is less than 200 km.

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[bobik]

While we are still patiently waiting for information about the implementation of the last Phobos flyby of Mars Express, the next flyby, in a series of close flybys, is due to take place at around 02:17:05 UTC on Tuesday, 9 January; passing within 55 km of the surface at closest approach.