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1. willia+(OP)[view] [source] 2023-07-31 11:37:37
I wonder why the reorientation is so infrequent? Is it a long process or a strain on hardware that you wouldn't want it to happen every day or even every month?
replies(3): >>Dalewy+l2 >>rvnx+2j >>csunbi+5J
2. Dalewy+l2[view] [source] 2023-07-31 11:54:40
>>willia+(OP)
Reorienting requires using a reaction wheel or propellent to move yourself.

Propellent is finite, so you want to use it as rarely as possible.

A reaction wheel is by itself infinite (assuming it doesn't break), but eventually it saturates and you need to desaturate it, which basically means spinning the wheel the other way while spending propellent to maintain position.

All of this is to say, reorientation is an expensive process especially if refueling isn't an option.

replies(2): >>curiou+zR >>Dylan1+3I1
3. rvnx+2j[view] [source] 2023-07-31 13:44:00
>>willia+(OP)
It costs fuel to reorientate
4. csunbi+5J[view] [source] 2023-07-31 15:20:37
>>willia+(OP)
In addition to the points made by sibling comments, there is always a chance something going wrong in the reorientation, so you do not want to do this more than necessary
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5. curiou+zR[view] [source] [discussion] 2023-07-31 15:51:28
>>Dalewy+l2
>reorientation is an expensive process

That’s true, but a failsafe automatic reorientation mode after two weeks with no communication from Earth might be a useful feature

replies(1): >>jjk166+G51
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6. jjk166+G51[view] [source] [discussion] 2023-07-31 16:47:50
>>curiou+zR
On the timescale of decades, does a 2 week vs a 10 week waiting period make much of a difference?
replies(1): >>curiou+Ab3
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7. Dylan1+3I1[view] [source] [discussion] 2023-07-31 19:42:11
>>Dalewy+l2
Reaction wheels only saturate by absorbing external acceleration, though.

You can reorient as much as you want with a reaction wheel, and the only cost is electricity.

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8. curiou+Ab3[view] [source] [discussion] 2023-08-01 07:36:43
>>jjk166+G51
>On the timescale of decades, does a 2 week vs a 10 week waiting period make much of a difference?

I agree. It probably doesn’t make much difference now. There are very unlikely to be any important data that will be lost. The mitigation process they already implemented seems prudent and sufficient

During earlier parts of the mission, like planetary encounters, it would make a difference. Even a two week wait could be much too long in those circumstances.

replies(1): >>jjk166+J24
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9. jjk166+J24[view] [source] [discussion] 2023-08-01 14:52:23
>>curiou+Ab3
Presumably during encounters the probe was in a different control scheme to keep its instruments pointed at the planet, as opposed to keeping its antenna pointed at Earth.
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