useless, but cool

quite

do

increase

Part of the problem is that you need is not precisely zero WRT the sun, but that you need something that is on the order of 1E-40 of its previous momentum about the sun. Otherwise it misses and becomes a problem again, of course this assumes that "dropping" that much mass (many megatons to several gigatons) into the sun will not have unwanted effects. A better plan may be to impact Mercury or Venus instead, much smaller targets, but far less to drop that much mass into.

Mercury and Venus are easier to hit than the sun? Wow, you learn something every day here on usenet.

John

quite

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increase

Momentum transfer is a useful tool to be sure, but there is a big difference between managing 5 tons at 1E-8 accuracy and managing 1E6 tons to 1E-14 accuracy. Say about a billion times the impulse required? How much would it take to loft a billion times the impulse available to voyager after Mars flyby?

The sun is about a degree wide as seen from earth. That's a pretty big target. Voyager 2 slingshotted Jupiter, then Saturn, then Uranus, then Neptune. A quad slingshot requires much higher precision than a simple dump into the sun. A few hundred million years from now, technology should be up to it.

The impulse is available almost for free, from other asteroids in the asteroid belt. Just slingshot them.

John

The sun is an easy target. Cancelling the delta-V of an orbiting body isn't so easy. Do the second and the first is a done deal. The only way to do it, in fact.

It is still easier to fling them out of the solar system entirely. And there is a *lot* more of it to aim for.

Although we tend to use one of the gas giants. Much more bang per buck.

Comets do crash into the sun and/or get very close indeed. SOHO data is released in realtime precisely so that keen amateurs can use software to search for them as professionals are not really that interested in them.

BTW the sun would barely notice if the Earth hit it head on.

There are a handful of old observations from noted comet seekers of comets that were brilliant one night setting just after the sun and never seen again (respected observers). They were generally not believed. These days SOHO shows the ones that go in but do not come out.

Regards, Martin Brown

In order to drop something into the Sun, you need to kill the orbital motion of the Earth (30 km/s).

Going from circular orbital velocity into escape velocity the speed needs to be increased by sqrt(2), thus the escape velocity from Earth's orbit is 42 km/s, thus the additional velocity is only 12 km/s, much less than ther delta-V required to drop into the Sun.

If you have some really nasty things (such as nuclear waste) that you would want to get rid of, do not send it to the Sun, but instead send it to the intergalactic space.

Paul

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Damn, you bruised my earthian pride. Just to help others what is the two masses?

must=20

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That ASSumes that there were zero course correction delta v available, which is false.

Where in the planets do you get this? Something must give them the initial nudge, plus we need the delta v to get that something out there.

A small rocket could slingshot a small asteroid around a bigger one and transfer momentum to it. That can be cascaded to the point that a massive asteroid could be flung out of the asteroid belt to a near-earth flyby. There's no reason why modest mid-course corrections couldn't be applied. The math of deflecting asteroids, even using current rocket technology, has been done, and it's feasible if you're careful.

People have done the math on this. It's just an engineering problem.

John

How about the 'Blink Drive'? ;-)