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Curiously Strong
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And yes, the acceleration issues for a woman in a difficult pregnancy is too much to be believed, even with the reduced gravity of Mars. But I presume when the 4th season arrives we'll get a look forward on how the Mars colony has survived!
Thanks to Mars’ lower gravity (and hence lower orbital velocity), ascent to low Martian orbit is downright leisurely compared to Earth. Ascent acceleration could be lower than 1 Earth g.
 
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Excellent.
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Thanks to Mars’ lower gravity (and hence lower orbital velocity), ascent to low Martian orbit is downright leisurely compared to Earth. Ascent acceleration could be lower than 1 Earth g.
What Kelly did is essentially the same thing that Mark Watney did in The Martian, except Kelly actually had more equipment. In the latter movie, Watney broke ribs and blacked out from the g-forces during the ascent. Serious question: which version is closer to reality? Or is the difference because Watney was traveling faster (“fastest man in the history of space travel”)?
 

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Premium Member
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They blamed NASA for the loss of jobs due to the new fuel (helium-3) found on the Moon.
I assume also they think the money spent by NASA could have gone to things like the homeless and so called bleeding heart causes rather than big business.
 

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Curiously Strong
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What Kelly did is essentially the same thing that Mark Watney did in The Martian, except Kelly actually had more equipment. In the latter movie, Watney broke ribs and blacked out from the g-forces during the ascent. Serious question: which version is closer to reality? Or is the difference because Watney was traveling faster (“fastest man in the history of space travel”)?
As I recall in The Martian, Hermes was making a high-speed flyby of Mars. It wasn’t in orbit. So he had to accelerate to greater than Mars’ escape velocity, not just orbital velocity.
 

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As I recall in The Martian, Hermes was making a high-speed flyby of Mars. It wasn’t in orbit. So he had to accelerate to greater than Mars’ escape velocity, not just orbital velocity.
It’s not as difference as you might think, Mars still has a pretty good gravity well. It’s around 4.1 km/s to low Mars orbit from the surface. Ground to a reasonable trans-mars injection orbit doing a flyby is around 6-6.5 km/s.

Mind you, that MSAM design is Hollywood Engineering. Don’t think you could make a methane-fueld SSTO that small even on Mars.
 

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Curiously Strong
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It’s not as difference as you might think, Mars still has a pretty good gravity well. It’s around 4.1 km/s to low Mars orbit from the surface. Ground to a reasonable trans-mars injection orbit doing a flyby is around 6-6.5 km/s.

Mind you, that MSAM design is Hollywood Engineering. Don’t think you could make a methane-fueld SSTO that small even on Mars.
Yeah, I checked the book and Hermes flyby was at 5.8km/s. I think the acceleration Kelly experienced was more realistic than Watney’s (though I totally don’t recall the specifics in The Martian).

Here’s a NASA presentation about a Mars Ascent Vehicle architecture: https://ntrs.nasa.gov/api/citations/20170003391/downloads/20170003391.pdf

That MAV doesn’t seem like it’s much bigger than the MSAM, but it requires staging for the methane version (so isn’t reusable). Notably, it does say “ascent acceleration of 0.8-1.5 Earth g’s.”
 

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Yeah, I checked the book and Hermes flyby was at 5.8km/s. I think the acceleration Kelly experienced was more realistic than Watney’s (though I totally don’t recall the specifics in The Martian).

Here’s a NASA presentation about a Mars Ascent Vehicle architecture: https://ntrs.nasa.gov/api/citations/20170003391/downloads/20170003391.pdf

That MAV doesn’t seem like it’s much bigger than the MSAM, but it requires staging for the methane version (so isn’t reusable). Notably, it does say “ascent acceleration of 0.8-1.5 Earth g’s.”
The MAV concept was staged and had about 4x the cabin volume in fuel + oxidizer. There’s nothing even close to that for the FAM MSAM.

But yeah, you could make a reasonable launcher from Mars at well under 2g
 

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Omega Consumer
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The MAV concept was staged and had about 4x the cabin volume in fuel + oxidizer. There’s nothing even close to that for the FAM MSAM.

But yeah, you could make a reasonable launcher from Mars at well under 2g
Is there enough of an atmosphere on Mars that maximum dynamic pressure would be an issue for the suited astronaut on the roof, aside from G forces?
 

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Is there enough of an atmosphere on Mars that maximum dynamic pressure would be an issue for the suited astronaut on the roof, aside from G forces?
That’s a good question, since it doesn’t take a lot of external pressure on you before you can’t breathe.

I’ll actually have to calculate that, but it could get pretty high. Going the other direction (aerobraking from a transfer orbit) it can hit 2 psi or so. It would be less in this case (your density drops as you speed up)
 

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I assume also they think the money spent by NASA could have gone to things like the homeless and so called bleeding heart causes rather than big business.
‘there was a callout in an earlier episode that nasa was self funding and they actually helped pay for other stuff in the federal budget
 

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All About Footwork
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I did love the fact that Ed apparently needed flying lessons. The guy who was either first or second on the list of best pilots in the entire U.S. needed to be taught how to land.

Also, didn't they say he would have about 3% fuel left when he started going down? he had 19% left when his daughter disengaged, I think...

Finally, they needed to shed 1,000 pounds. 7 people don't weigh more than 1,000 pounds? each man alone is at least 220.
 

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Now with flavor!
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I wonder if they might have the Soviet Union break up in Season 4.
According to the podcast, (haven't listened to) Roscosmos (Soviet space program) will be the focus of season 4. I'm sure the writers can work in an overthrow of the Communist govt lickety-split.

Do we have a clue why the terrorists were mad enough at NASA to do this?
Being anti-space was trendy since Fusion killed off Oil and Coal industries and put thousands out of work. Conspiracists believed of a huge cover-up with Gordo and Tracy's deaths. And a lot of what happened during the crisis was probably covered up by both American and Soviet governments. (the second reactor was never disclosed)

That former Jamestown astronaut in on the conspiracy was a marine, the failed LSAM pilot. He refused to accept the circumstances of his comrade's death too.
 
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