a reply to:
theatreboy
Just about anything below Low Earth Orbit and below orbital velocity (roughly 17,000 mph) will deorbit eventually. In order to achieve orbital
velocity most rockets need to do two things, they need to continue to accelerate after launch, and in order to do this they must at the same time shed
mass. This is why rockets have 'stages'. The portion of the space vehicle which actually reaches orbit is very small (tiny almost) in comparison to
what got launched.
Accelerating through the lowest parts of Earth's atmosphere takes the most power and therefore requires the most fuel which results in the most weight
and the largest 'gas tank' (if you will). This part of the rocket separates early in the launch sequence (usually around 60 seconds or so). Because
it is so low, these stages usually fall back to Earth intact. Some of these land precisely back on Earth like the Space X system, for example.
The middle stages of the vehicle travel much further up into the atmosphere. But these pieces still don't reach orbital velocity before they separate
from the vehicle. Depending on where the separation occurs, these sections can either fall back to Earth right away, generally burning up on
re-entry, or they can continue to orbit for a while in a steadily declining orbit. These are likely the sections we have been seeing lately. Plus,
there are a lot more space shots going on today around the World than there ever have been in the past, so...there's just more space junk falling back
to Earth than ever before.
Now, a word about solar storms. A solar storm, or CME, alone will not knock a spacecraft out of orbit. Most spacecraft are largely unaffected by all
but the strongest of these storms. When orbital craft do get affected by some solar event it is generally a result of some sort of a power issue.
The solar event knocks out power to the satellite or vehicle and causes it to be unable to orient its solar arrays properly and/or receive commands
from Earth to 'boost' (i.e. raise) its orbit. When this happens, and if the condition doesn't correct itself, the orbit of a satellite or vehicle can
'decay' where it slows down and descends. Once it reaches a certain point in the atmosphere the friction from the atmospheric density acts like a
braking effect and slows the vehicle down rapidly to where it eventually falls from orbit. But this type of thing is very rare.
Most people don't realize that orbiting the Earth is not the same as deep space travel, it is not free from Earth's gravity. When orbiting the Earth,
an object is constantly falling toward the Earth, but it's traveling forward at such a velocity that it misses the Earth (repeatedly). As long as the
velocity and altitude of the object is maintained the object will remain in orbit, but if either of these two values drop below certain thresholds
then the object will de-orbit and fall to Earth, largely burning up in the process.
Lastly, I could go into a phenomenon known as a "cascade" which is a result of objects colliding in space creating a storm of flying space debris
which takes out progressively more 'other' space vehicles, further compounding the firestorm and hail of space debris and shrapnel, but fortunately
(for now anyway) this has never happened. It is, however, a possibility in the future if we don't police our space junk carefully. "We" in this case
is any country sending objects up into orbit.
edit on 5/27/2024 by Flyingclaydisk because: (no reason given)