Asteroids and the Gravity Tractor

[Runewolf1973]

Just curious if anyone has heard of the concept called the Gravity Tractor. That is the idea of using a spacecraft to affect the gravity of an asteroid and thereby causing it to divert a potential collision course with Earth.
http://en.wikipedia.org/wiki/Gravity_tractor

My question about this is in regards the speed of an asteroid...

From my understanding, asteroids can travel tremendous speeds, some reaching 50,000 miles per hour or more. So say that a potential planet killer is headed towards Earth, but it is moving at 30,000 miles per hour...for instance. If this were the case, then how would it even be possible for our spacecraft to catch up to an asteroid that is moving at that speed? How can you orbit or even get close to something going 30,000 miles per hour?

 

[MrOmega]

Great question.

In any event, people love thinking BIG!

One possible alternative might be a laser shot into the sky burning the asteroid off trajectory.





Little secret people keep. Gravity is poorly understood. Straight from NASA.

Decrypting the Eclipse - NASA Science

In a marathon experiment, Maurice Allais released a Foucault pendulum every 14 minutes - for 30 days and nights -without missing a data point. He recorded the direction of rotation (in degrees) at his Paris laboratory. This energetic show of human endurance happened to overlap with the 1954 solar eclipse. During the eclipse, the pendulum took an unexpected turn, changing its angle of rotation by 13.5 degrees.

Maurice Allais (1911 - ) won the Nobel Prize in Economics in 1988. He stated, "All my researches in theoretical and applied physics which, at first sight, appear to be remote from my main activity as an economist, have, in reality, enriched me with valuable experience."

Who knows? Maybe spin technology is the answer, which is waiting for discovery?

From my understanding, asteroids can travel tremendous speeds, some reaching 50,000 miles per hour or more. So say that a potential planet killer is headed towards Earth, but it is moving at 30,000 miles per hour...for instance. If this were the case, then how would it even be possible for our spacecraft to catch up to an asteroid that is moving at that speed? How can you orbit or even get close to something going 30,000 miles per hour?

They say Ion Propulsion is the next big leap in technology.

Straight out of Star Trek. The space craft bound for Ceres supposedly uses that technology.

http://www.nasa.gov/centers/glenn/about/fs21grc.html

The trick in space is the acceleration, so... getting enough fuel into space to reach that speed, as there is no friction, or little friction is the big challenge.

 

[Runewolf1973]

Thanks for the reply, MrOmega!

Hmmm... I wonder. If it's possible to build a gravity tractor, maybe it's possible to build some sort of gravity net. That is using the gravitational pull of a few spacecraft to create like an artificial keyhole effect to catch a very fast moving asteroid within it's "web" and thereby redirect it's course. Kinda like how a spider catches very fast flying insects in it's web. Just a thought...

 

[Freelance_Policeman]

How, exactly, are we to procure a spacecraft with a gravitational field strong enough to alter the course of an asteroid? We would need something the size of Pluto at least.

 

[MrOmega]

Yes, the currently accepted and totally believable theory of gravity connects mass to gravity.

There is no mention of spin in the equation.

Newtons Big G will solve gravitational calculations till Mercury is in question. So they say at which point Einsteins General relativity is required.

Gravity waves are used in weather forecasting and this is interesting, saying the least.

[youtube]yXnkzeCU3bE[/youtube]
Gravity Wave - YouTube

Mind you, what gravity looks like and what the effects of gravity are might be different.

The Cavendish Experiment is the classical experiment used to prove that mass and gravitational force are directly related.

Who knows? The Cavendish Experiment performed in space might be something yet to be done.

Perhaps spin is somehow directly related with Gravity, if people looking at the Focault Pendulum experiment will find no other answers for the perturbed motion of the pendulum during an eclipse.

Other possibilities may be some sort of electromagnetic relationship.

The short answer. Peoples understanding of Gravity is supposedly incomplete.