Surviving a Solar Storm: The Challenges of Monitoring Earth from Mars

[Chatterton]

Hi! I'm playing around with an idea for a story set on an orbiter around Mars. While Mars and Earth were on opposite sides of the sun, Earth got hit by a colossal coronal mass ejection even bigger than the Carrington event of 1859. So they see Earth rise but can't pick up any radio signals (figuring the problem's on their end at first). My big question is . . . how long will it take before they can see enough of the nighttime side of Earth to figure out there's no more power grid?

 

[rootone]

If the orbiter has a pretty good telescope aboard they should be able to resolve the Earth enough to see it as a globe instead of a few pixels.
However when Mars is exactly the opposite side of the Sun from Earth there are two problems:
First, the Sun might be in the way of making any observations of Earth or communications with Earth.
This happens regularly with the present rovers on Mars, so they get put into a resting mode.
Secondly, even if the Sun is not in the way, the night side of Earth won't be visible.
After the point of exact opposition is past. they will see increasingly more of Earth's night side.
I'd guess it might be a month or maybe two before enough of the night side is visible for a conclusion to be drawn that all the lights on Earth had gone out.

For your story, the likely sequence of events is that the Mars orbiter is fully expecting to lose communications with Earth for several days, and is fully expecting that Earth will back in contact after that.
... but then things start to get not as planned ...

 

[Chatterton]

Thanks, rootone.
And yes, things do start to get not as planned.

 

[Gigaz]

I don't think its a very realistic scenario anyways. For a manned Mars mission there would certainly be a transmitting probe somewhere in an orbit that allows the astronauts to communicate with Earth even when it is behind the sun. And at least some emergency power supply would be back on again within minutes after a huge CME.

 

[Chatterton]

And at least some emergency power supply would be back on again within minutes after a huge CME.

Well, let's discuss that point, because I'm getting conflicting answers on that. There are some saying that if it were big enough it could fry the whole power grid. There's speculation that if the CME of 2012 had been a direct hit it would've taken 4-10 years to get everything back online.

 

[rootone]

...some emergency power supply would be back on again within minutes after a huge CME.

Very likely, but would communicating with the Mars orbiter have much of a priority in these circumstances?

 

[jim hardy]

Do we not get advance warning of those things ? Surely they'd get warned comms might go down for a while.

The fastest Earth-directed CMEs can reach our planet in as little as 15-18 hours. Slower CMEs can take several days to arrive.

https://www.swpc.noaa.gov/phenomena/coronal-mass-ejections

 

[rootone]

Do we not get advance warning of those things ?

Yes, but there may not be enough time to get the warning to the Mars orbiter before the anticipated radio silence.
Room there for some political intrigues in the story
Still though. you have to get some guns into the story before hollywood will be interested.
Though I guess a romantic bit without going into sex might work.

 

[Chatterton]

My idea for the story is to have the POV entirely from the perspective of the people on the ship. So, if you're on a ship millions of miles from home with depleted fuel and food reserves and it looks like home just went back to the dark ages, from their perspective the amount of advance warning would be a bit of a moot point.

If the power grid had to be rebuilt from scratch, retrieving some astronauts from Mars would likely be one of the lowest priorities imaginable. And everyone on board would know that. Does that make any sense?

I like the idea of the relay satellite though. But I'm pretty sure it would give a limited stream of info, much like the way the ISS gets a limited feed filtered through the space agencies.

 

[Chatterton]

Still though. you have to get some guns into the story before hollywood will be interested.
Though I guess a romantic bit without going into sex might work.

I know where to find guns on the ISS (a 9mm in every Soyuz capsule, just in case things go way wrong on re-entry), but I can't justify guns in orbit of Mars. Complicated relationships, though. I got you covered!