XPost: alt.astronomy

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Answered by
Silk Road

Oct 20
Rather than crashing the ISS into the atmosphere as planned, could
booster rockets be attached and have it move to a Lagrange point or to
an orbit higher than the geosynchronous ones?

Let's start with why they want to crash the ISS into the atmosphere in
the first place.

Our beloved ISS is getting old and it's expensive to maintain. It costs
about $3-4 billion per year to keep it running, and that money could be
used for other space missions.

Plus, the ISS is constantly losing altitude due to atmospheric drag, and
it needs regular boosts from visiting spacecraft to stay in orbit.

If they don't do that, the ISS will eventually fall back to Earth on its
own, and that could be dangerous if it hits a populated area.

So they have a plan to deorbit the it safely around 2028-2030, by using
a special module called the Progress spacecraft.


This is a Russian cargo ship that can dock with the ISS and push it down
with its engines.

They will aim for a remote area in the Pacific Ocean, where the ISS will
burn up and break apart during reentry.


Now back to your question. For those that don't know, a Lagrange point
is a special location in space where the gravitational forces of two
bodies (like the Earth and the sun) balance each other out, so an object
can stay there without much effort.

The answer to your question is technically yes, they could do it. But it
would be very hard and very costly. Here's why:

The ISS is not designed to go to a higher orbit or a Lagrange point.


It's optimized for low Earth orbit (LEO), which is about 250 miles (400
km) above the surface.

To go higher, it would need more powerful engines, more fuel, more
shielding from radiation and micrometeoroids, and more cooling systems
to deal with the higher temperatures.

The ISS is enormous.


It weighs about 420 tons (380 metric tons) and has a wingspan of 357
feet (109 meters). To move it to a higher orbit or a Lagrange point, it
would need a lot of thrust and delta-v (change in velocity).

For example, to go from LEO to geostationary orbit (GEO), which is about
22,000 miles (36,000 km) above the equator, it would need about 4 km/s
of delta-v.

To go from LEO to L2, which is one of the Lagrange points on the
opposite side of the Earth from the sun, it would need about 3.5 km/s of delta-v. That's a lot of fuel and rockets.

The ISS is not one piece.


It's made of many modules that are connected by bolts and wires. To move
it as a whole, they would need to make sure that all the connections are
strong enough to withstand the stress and vibration of the rockets.

They would also need to coordinate the firing of the rockets so that
they don't cause unwanted torques or rotations on the ISS.

The ISS is not alone.


It has many visitors, like astronauts, cosmonauts, taikonauts, robots, satellites, and space junk.

To move it to a higher orbit or a Lagrange point, they would need to
make sure that none of these visitors interfere with the maneuver or get
left behind.

They would also need to plan for future visits, which would be more
difficult and expensive at a higher altitude or a different location.

The bottom line:

Moving the ISS is not impossible, but it's very impractical. It would
take a lot of time, money, and resources that could be better spent on
other things.

Plus, there's not much benefit in doing so. The ISS has already done a
lot of amazing science and exploration in LEO, and there are other ways
to continue that legacy in space.


It's sad to see it go, but it's also a way to celebrate its achievements
and make room for new adventures.

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XPost: alt.astronomy

"a425couple" wrote in message news:GHb_M.198964$w4ec.137816@fx14.iad...

Let's start with why they want to crash the ISS into the atmosphere in
the first place.

Our beloved ISS is getting old and it's expensive to maintain. It costs
about $3-4 billion per year to keep it running, and that money could be
used for other space missions.
-------------------

https://www.cnet.com/science/cosmonauts-drill-into-iss-to-repair-air-leak-cracks/
"The minor leak appears to have been caused by two tiny cracks in the
module's transfer chamber. The chamber includes a docking port for
spacecraft. In a statement last week, Roscosmos said one of the cracks was
less than an inch long."

Brittle metal cracks when stressed, flexible metal bends or stretches. Unfortunately the means of strengthening metal such as alloying or hardening and strengthening it to enable using less in weight-critical applications
tend to make it more brittle, particularly for aluminum alloys. Welding also erases previous heat treating and creates local stresses from shrinkage as
the weld area cools. This is why steel ships can be welded while aluminum aircraft are riveted or glued.

https://en.wikipedia.org/wiki/Manufacture_of_the_International_Space_Station

Cracks are usually undetectable at first and finding large ones means that
more are likely to develop in the future unless the structure stops flexing from use.

Drilling a hole at the end of a crack expands the area being pulled apart
and spreads the force, reducing it at each point. It's a standard practice
when bending sheet metal: https://sendcutsend.com/blog/guide-to-designing-bend-reliefs/

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XPost: alt.astronomy

"a425couple" wrote in message news:GHb_M.198964$w4ec.137816@fx14.iad...

Let's start with why they want to crash the ISS into the atmosphere in
the first place.

Our beloved ISS is getting old and it's expensive to maintain. It costs
about $3-4 billion per year to keep it running, and that money could be
used for other space missions.

------------------------------------

https://en.wikipedia.org/wiki/Zvezda_(ISS_module)
"It was the third module launched to the station, and provided all of the station's life support systems, some of which are supplemented in the US Orbital Segment (USOS), ..."

"The Mir space station and Zvezda had the same design problem of launching
with all the hardware permanently installed. Russian (and Soviet) space doctrine has always been to fix the hardware onboard instead of simply replacing them like the US Orbital Segment (USOS) does with the 41.3 inch
(105 cm) wide International Standard Payload Racks that can easily fit
through the 51 inch (130 cm) wide hatch openings through the modules
connected via the Common Berthing Mechanism (CBM). This means broken but unfixable hardware onboard the Mir modules and Zvezda end up being stuck
there forever and can not be replaced."

"Another reason why Elektrons can not be replaced is because the three
Elektron units that were launched on Zvezda were the last units ever manufactured. The original manufacturers went out of business and the single engineer who made the tweaks for the Elektrons that were installed on Zvezda died with all his secrets and knowledge not passed to anybody else."

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