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NASA's DART spacecraft changed an asteroid's orbit around the sun

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Re: NASA's DART spacecraft changed an asteroid's orbit around the sun

#51

Post by bdamm »

Ajakks wrote: post #46
redman25 wrote: post #31

Earlier quoted context omitted.

First things first, we have to colonize the rest of the solar system before we can terrorize Earth.

Why exactly? I think the US ought to spend a few trillion on an actual space battleship - one that never comes down to the surface, just sits in orbit. There was a project regarding dropping telephone pole sized pieces of metal from space as an offensive weapon - put something like that on the space battleship and... That is simply "Assured Destruction" with absolutely no mutual drawbacks or lingering consequences li…

You've described a space station, which three countries have already done independently (Mir, SkyLab, Tiangong).

But dropping rods from an orbiting platform makes no sense. There's a reason that "Rods from God" didn't pan out, and it has to do with orbital dynamics. Neither Bezos nor Musk can do it, because it actually doesn't work.

Re: NASA's DART spacecraft changed an asteroid's orbit around the sun

#52

Post by rkagerer »

mikeyouse wrote: post #41
infinitewars wrote: post #39

> slowed the orbit of a pair of asteroids around the sun by more than 10 micrometers per second Or in other words, 1 meter per day Why not say that?

Because the SI unit is meters per second, so maintaining the “second” gives people with that understanding a basis in which to compare the delta-V.

I'm genuinely curious whether there are a substantial number of people out there who deal on a regular basis with dV's on such a minute scale. Who would that be, outside an asteriod-redirect program such as this? Satellite operators doing precision trajectory correction?

I found the meter per day conversion helpful. Through another lens, it's about 0.000036 km/hour (or about 1.5 inches per hour).

Re: NASA's DART spacecraft changed an asteroid's orbit around the sun

#53

Post by anigbrowl »

Ajakks wrote: post #49
bhhaskin wrote: post #48

Earlier quoted context omitted.

The technology doesn't exist and it would be a huge waste of money. How heavy would a telephone pole sized tungsten rod be? What happens when China, Russia, India or Pakistan find out you are building this (cause you can't hide it if it's in near earth orbit)? They would either knock it out of the sky or hit you with everything they have. We would do the exact same if anyone else was developing such a weapon.

I personally would get whatever metal in space, so weight is not the issue - solving this problem would also create almost immediately chunks of rocks that could also be dropped. In all reality, anything can be "setup" to be a weapon - many ways have been identified here. All required innovations - of which, most are not out of reach in the slightest, all of that tech would be immensely valuable, literally everything…

If this is satire, it's not that funny. If you're serious, it's a good example of 'the ugly American.'

Re: NASA's DART spacecraft changed an asteroid's orbit around the sun

#55

Post by Ajakks »

bdamm wrote: post #51
Ajakks wrote: post #46

Earlier quoted context omitted.

Why exactly? I think the US ought to spend a few trillion on an actual space battleship - one that never comes down to the surface, just sits in orbit. There was a project regarding dropping telephone pole sized pieces of metal from space as an offensive weapon - put something like that on the space battleship and... That is simply "Assured Destruction" with absolutely no mutual drawbacks or lingering consequences li…

You've described a space station, which three countries have already done independently (Mir, SkyLab, Tiangong). But dropping rods from an orbiting platform makes no sense. There's a reason that "Rods from God" didn't pan out, and it has to do with orbital dynamics. Neither Bezos nor Musk can do it, because it actually doesn't work.

I doubt it was seriously considered at the time it was discussed. Space Stations are in orbit - the space battleship doesn't have to be, that is very significant.

Earth is spinning in a giant circle around the sun. Thats facts. "aiming an asteroid" is less of making a rock a missile - and a lot more of tug-boating it into the exact right spot, in the way of earth, so that earth hits the asteroid - not anything complicated like the asteroid hitting earth.

There are a lot of little things like that...

Re: NASA's DART spacecraft changed an asteroid's orbit around the sun

#56

Post by nashashmi »

tgv wrote: post #33
nashashmi wrote: post #30

Earlier quoted context omitted.

Slight changes can cause such impacts? Now imagine how many other meteors and comets also will be adjusting because of this. Will one of them once on a course to never hit earth suddenly shift to hit earth in a thousand years time? The confidence i get is the opposite

I don't think asteroids (like the target) have influence on others. There's so much space between them, and their mass is almost neglible.

Oh no. I was not talking about the other objects that float through space influenced by such a small object so far away.

I was talking about the sun shaking in its orbit because high velocity objects are now pulling at it differently causing other objects to be influenced by the new position of the sun.

I read the parent comment as “solar orbit change” meaning the sub was changing position.

Re: NASA's DART spacecraft changed an asteroid's orbit around the sun

#57

Post by ordu »

cdelsolar wrote: post #32
birdsongs wrote: post #20

Earlier quoted context omitted.

Inflammable made me so angry as a child/teen when I found out. I read it in our encyclopedia set but we didn't have a dictionary, and this was pre-internet. It was in the context of hydrogen and I could have sworn it was flammable. But here is this encyclopedia telling me it's INflammable. It's... not flammable? Looked it up in the school library. Thank you, that memory came up from the depths of time. Probably haven…

Inflammable means flammable? What a country!

It is logical: to inflame means to set on fire. Though, I agree, confusing.

Re: NASA's DART spacecraft changed an asteroid's orbit around the sun

#58

Post by MisterTea »

redman25 wrote: post #31
wongarsu wrote: post #28

Earlier quoted context omitted.

You know what they say: the best planetary offense is a good asteroid redirect program It's also the best planetary terrorism, going by the plot of The Expanse

First things first, we have to colonize the rest of the solar system before we can terrorize Earth.

> before we can terrorize Earth.

Before?! We're already doing a great job at it!

Re: NASA's DART spacecraft changed an asteroid's orbit around the sun

#59

Post by aw1621107 »

Ajakks wrote: post #55
bdamm wrote: post #51

Earlier quoted context omitted.

You've described a space station, which three countries have already done independently (Mir, SkyLab, Tiangong). But dropping rods from an orbiting platform makes no sense. There's a reason that "Rods from God" didn't pan out, and it has to do with orbital dynamics. Neither Bezos nor Musk can do it, because it actually doesn't work.

I doubt it was seriously considered at the time it was discussed. Space Stations are in orbit - the space battleship doesn't have to be, that is very significant. Earth is spinning in a giant circle around the sun. Thats facts. "aiming an asteroid" is less of making a rock a missile - and a lot more of tug-boating it into the exact right spot, in the way of earth, so that earth hits the asteroid - not anything compli…

> Space Stations are in orbit - the space battleship doesn't have to be

I mean, you did say:

> space battleship - one that never comes down to the surface, just sits in orbit.

So I think it's understandable for people to take that at face value.

Furthermore, if it isn't in orbit, then where would it be?

> and a lot more of tug-boating it into the exact right spot, in the way of earth, so that earth hits the asteroid - not anything complicated like the asteroid hitting earth.

From an orbital mechanics standpoint I don't think there's actually a difference. You're changing an orbit either way.

Re: NASA's DART spacecraft changed an asteroid's orbit around the sun

#60

Post by MisterTea »

Ajakks wrote: post #46
redman25 wrote: post #31

Earlier quoted context omitted.

First things first, we have to colonize the rest of the solar system before we can terrorize Earth.

Why exactly? I think the US ought to spend a few trillion on an actual space battleship - one that never comes down to the surface, just sits in orbit. There was a project regarding dropping telephone pole sized pieces of metal from space as an offensive weapon - put something like that on the space battleship and... That is simply "Assured Destruction" with absolutely no mutual drawbacks or lingering consequences li…

> . There was a project regarding dropping telephone pole sized pieces of metal from space as an offensive weapon

I remember it was nicknamed "Rods From God". Kinetic energy weapon using 9 ton tungsten rods dropped from an orbiting platform. https://en.wikipedia.org/wiki/Kinetic_bombardment

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