How exactly will the ISS die in 2025? [duplicate]

Question

According to:

”Moreover, the ISS end of life might come in 2025, and assuming you need a few years to graduate, more to get a degree, work experience, get hired, do the training... The ISS might not exist at that point anymore.” Antzi

I begin to have many thoughts of how ISS will die when we’ll reach that year.

What was in my mind?

1. I was thinking NASA will take step by step parts from ISS.
2. I was thinking that NASA will plant a bomb in ISS and evacuate every member of ISS.
3. I was thinking that ISS will break apart naturally.

Can anyone please tell me how will ISS will end? Because, now I’m started to be curious how will that happen.

I tried to find on Internet, but my search has failed

Answer 1

Left alone, the ISS would eventually re-enter the atmosphere within a couple of years due to the tiny amount of atmospheric drag at its current orbital altitude. That scenario isn't desirable, because it's very hard to predict where a natural re-entry like that will eventually land, and we don't want 400 tons of space junk to fall on someone's house. The ISS is periodically re-boosted to maintain its altitude.

Instead, when the decision is made to bring the ISS project to an end, it will be tanked up with extra fuel, and one or more unmanned Progress service craft will be used to make a reentry burn that drops the station in such a way that all the debris will fall safely into the ocean rather than on land.

No bombs need to be placed; the heat and force of reentry will break the station up pretty well. Some interior equipment may be salvaged (unlikely to be of much use to future missions; they'll probably be museum pieces) but none of the major components of the station can be re-used; they will be badly damaged or destroyed by reentry and splashdown.

Finally, 2025 is more than two US presidential elections in the future. Regardless of how the future plans for ISS stand at the moment, a lot could change between now and then.

Answer 2

The hypersonic research facility where I work is currently involved in this question.

As mentioned above, the orbit of the ISS would eventually decay due to atmospheric drag. Over its life this has been addressed by several methods; at night the solar arrays are rotated to limit the (very tiny amount of) drag from the upper atmosphere, and the space shuttle had on more than one occasion docked with the ISS and used its manoeuvre thrusters to place it back in a higher orbit. Don't quote me on this but I believe this is the main reason for retiring it, now the shuttle is no longer used; there's no way to fix the decaying orbit any more. The fact some of the computers on board are late 90s technology is another reason.

As also mentioned above, letting it fall down naturally is a bad thing; it needs to be deorbited with a degree of precision. It's outside my area but this would likely be done with a small booster mounted on the front of the station. The plan is to aim near the east coast of new Zealand and put it down in the pacific Ocean. This is the main area of interest; if it doesn't break up correctly, some parts might reach the west coast of the USA; parts of mir hit the land instead of the ocean, and mir was a lot smaller then the ISS.

The deorbit profile is also important; it needs to be bought down at a shallow enough angle to allow it to burn up as much as possible (but too slow would risk it being over the USA). Bringing it in at a steeper angle prevents it from reaching the USA but doesn't give enough time for it to burn up, meaning most of it will hit the ocean (or land if someone really miscalculates). Such a large object hitting the ground causes its own problems.

As for what actually happens, this is part of what we've been researching with small scale models in a hypersonic wind tunnel. The solar panels will tear off fairly quickly when it hits the atmosphere. The modules do break apart and tumble away eventually, but there is also some merit in decoupling them from each other first; they spread out more during reentry (more likely of hitting something on the ground) but less likely of coming down in one huge heavy lump.

So as you see, it's a difficult task to do safely.

Answer 3

Russell's answer discusses what will actually happen, so I'll just comment on your suggestions.

1. I was thinking NASA will take step by step parts from ISS.

This would be extremely expensive and would just move your question one level farther back: how would they get the parts back to earth?

2. I was thinking that NASA will plant a bomb in ISS and evacuate every member of ISS.

That would be a really bad way of dealing with it. It would turn the ISS into 400 tons and billions of pieces of space junk. Basically, all the bits of the ISS would be whizzing around in orbit at high speeds, colliding with everything else that's up there and damaging and destroying it. At the speeds involved, even small particles of debris can have large amounts of kinetic energy and cause serious damage to whatever they hit. (Think about how fast things are thrown out of explosions. On earth, they get slowed down a lot by air resistance; not so in orbit.)

3. I was thinking that ISS will break apart naturally.

It will but then you have the problem that it just falls wherever it falls and, because the ISS is so big, parts of it will reach earth. That could happen anywhere between about 52° north and 52° south, which includes most of the world's major populated areas.

Answer 4

Some say the ISS will die in fire
Some say it will be towed into a graveyard orbit
But from what I've tasted of the expense of heavy lift rockets,
I hold with those that favor fire.
But if it had to perish twice,
I think I know enough of orbital mechanics
To say that for disassembly and module reuse
Is also great
And would suffice.