4 ms·
not really sure if having a nuclear reactor would make much of a difference in this case
by ilogik 6y ago
not really sure if having a nuclear reactor would make much of a difference in this case
- taneq 6y agoEven if there's no radiation risk, they're pretty dense and heavy. We use depleted uranium in armour-piercing rounds for a reason.
- TeMPOraL 6y agoWhich would be a nice thing to have in a collision, as more pieces would keep tighter together and closer to original orbit. Having a nuclear reactor onboard is the opposite of a problem in a case like this.
- dmurray 6y agoWouldn't the other, lighter, satellite experience the opposite though? It would be like a road collision: you'd rather have two small cars collide than a car and a semi-truck, assuming the same speeds. The truck has more kinetic energy to send fragments of the car flying everywhere. Clearly you'd rather a collision between two 1kg satellites than two 1000kg ones - where does this logic break down as we make one or both sats bigger?
- TeMPOraL 6y agoThe reason you prefer cars to be lighter if they're going to get into collision is because cars can absorb only so much kinetic energy before it spills out and affects the squishy humans inside. You're optimizing for safety of the passengers of both cars simultaneously. Satellites don't have this constraint. Of course you'd generally prefer smaller sats to collide (smaller = less fragments), but assuming fixed size, denser (= heavier) pieces will have more inertia, and so deviate less from their original flight path. This keeps the debris trail more concentrated. If only one of the two is heavy, the pieces of the heavier one should end up more concentrated. I'm not sure whether the wreckage of the lighter one gets spread more widely, or - with these velocities - just flash-fuses itself with the heavier one.
- admax88q 6y agoIs it? More mass means more kinetic energy. If the core of the satellite is extremely heavy, it only has to lose a tiny percentage of velocity to send a lightweight piece off at 90 degrees at extremely high velocities. Taken to the extreme I'd rather hit a feather than a bowling ball at 14 km/s.
- TeMPOraL 6y ago> Taken to the extreme I'd rather hit a feather than a bowling ball at 14 km/s. But what matters here isn't what you would rather do, it's what both you and the feather/bowling ball would rather do, in context of minimizing the size of the resulting fragmentation. Intuition tells me that a hypervelocity bowling ball will barely notice you, much less have time to deposit lots of energy into you.
- admax88q 6y agoSure not a great example, but fire two bowling balls at eachother and fire two feathers at eachother at equal speeds, how big do you expect the debris fields to be in either case? The bowling ball collision has a lot more energy involved, it can eject more debris at high velocities in various directions.
- taneq 6y agoDepends what else shares that orbit, or crosses its path at close orbital distances, doesn't it? If it does break up into pieces then you have a slowly dispersing shotgun blast of heavy metals polluting a wide range of orbits. If it doesn't, you have one tiny hard-to-track but very massive cannonball lurking out there waiting to strike. The heavier the fragments and the less eccentric the orbit of untracked space junk, the more dangerous it is, because the longer it'll be hanging around before it gets close enough to Earth to de-orbit itself.