Recent comments in /f/space

PandaEven3982 t1_j6nr9b0 wrote

Reply to If the concepts of Project Orion were proven, why don't we use them for space guns? by [deleted]

What you are missing is that it wasn't stopped by treaty. It was stopped by engineering saying we won't build it, its too much risk at our current state of art. TBH, even with as little fallout as we can design, it's really dangerous when its inside a gravity well. Mine the fissile material from asteroids, build it in Lunar orbit? Sure!

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FSYigg t1_j6nr622 wrote

Reply to comment by robertojh_200 in 2 big pieces of space junk nearly collide in orbital 'bad neighborhood' by jeffsmith202

Space X isn't the only entity that's been delivering payloads to orbit for the last 60 years or so, is it?

This problem isn't over-sensationalized, if anything it's been ignored.

Most of the stuff that was put up there remains up there even though it died years ago. That's the nature of putting things in orbit - They tend to stay there.

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[deleted] t1_j6nqxor wrote

Reply to comment by Musicfan637 in A spaceflight disaster was narrowly avoided in 1972. A series of intense solar flares exploded in August, just months before the launch of Apollo 17. Any astronauts on the moon at that time would have died from radiation. As NASA's new lunar missions progress, the threat of radiation still looms. by EricFromOuterSpace

The concept is simple, you just include an emergency shelter with higher radiation shielding. Solar storms don't last for long.

The execution of that concept is more nuanced, but for a lunar outpost, the easiest solution is simply to build a bunker into (by digging) or out of (by forming a concrete) the lunar soil.

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FSYigg t1_j6nqqwe wrote

Reply to comment by ClearlyCylindrical in 2 big pieces of space junk nearly collide in orbital 'bad neighborhood' by jeffsmith202

Oh yeah. That must be the only thing that's up there in what they referred to as "a bad neighborhood," huh?

What happens to decommissioned satellites? Most of them are just abandoned in place and then they just slowly drift out of orbit.

I read the article. You should look past it. This isn't just the result of a handful of recent launches. This stuff has been building up in orbit for decades.

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svarogteuse t1_j6npt7i wrote

Reply to comment by [deleted] in If the concepts of Project Orion were proven, why don't we use them for space guns? by [deleted]

What you are looking for is explicitly spelled out in the Space gun article that I already linked and you couldn't find in the section Technical Issues.

>the acceleration would theoretically be more than 1,000 m/s2 (3,300 ft/s2), which is more than 100 g-forces, which is about 3 times the human tolerance to g-forces of maximum 20 to 35 g[5]

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cjameshuff t1_j6nn9ty wrote

Reply to comment by A40 in If the concepts of Project Orion were proven, why don't we use them for space guns? by [deleted]

Yeah, even ignoring the politics, Starship should be able to get launch cost <$200/kg, lower than just the energy costs for the space elevator in Edwards' study. You're not going to get launching something with a nuclear fission bomb and a massively hardened nuclear space gun to be lower than that, just due to the costs of the bomb itself, never the massive propellant costs and complications of snagging it from a suborbital trajectory with a Starship.

Just put the payload on a Starship.

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svarogteuse t1_j6nn0xt wrote

Reply to comment by [deleted] in If the concepts of Project Orion were proven, why don't we use them for space guns? by [deleted]

No the g-forces wont exclude humans. A proper Orion craft has a payload section and a pusher plate. The pusher plate and the payload are separated by massive shock absorbers to minimize the forces exerted on the payload.

>Two shock absorber designs were explored. The first consisted of three donut-shaped gas-filled cushions, each one meter high, looking like a stack of tires. Six-meter high aluminum pistons rose from these absorbers. This system would limit peak G forces to 3 to 4 G's. But it would be a bumpy ride for the passengers. Therefore the second design was more complex but allowed the shock absorbers to operate in synchronization in order to further even out the G-forces. This would limit peak forces to 1.5 to 2.0 G's.

1.5 -2.0 Gs is less than the 6Gs of early rockets and the 3 of the shuttle.

$200k and radiation over an area, downwind from the fallout and environmental damage noticeable across the world. We didnt stop Orion strictly because of the treaty. If it had been viable (ie worth the environmental damage) we would have negotiated it into the treaty.

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