As I understand it,:p every action has an equal and opposite reaction, as space is a vaccume, exactly what resistance do the rockets have to push against to give tthem their forwards thrust?

You’re being serious, aren’t you? 😮

Fear not. Help is at hand.

Who said it was easy?

Unless Newton actualy went up into Space, you are assuming that Newtons 3rd would work in space.I however would disagree with you 😉

It’s a good job that the Universe disagrees with you then, otherwise rocket motors wouldn’t work in space.

There is resistance though. Inertia doesn’t cease to exist in a vacuum and would still present a great resistance, at those speeds, to a change in direction.

But even the tiniest deflection applied over enough time, preferably over years, may well be enough to avoid impact.

Hence why early detection is so vital.

Ah well, no point in worrying about it. The one with our planet’s name written on it will probably come in from sunward and we’ll literally never know what hit us.

That doesn’t affect its mass. Bearing in mind that at a distance of 1AU the sun exerts a force of only 9 newtons per square mile with its light output, surely it would take one hell of a solar sail to deflect something with the size and energy of a meteor?

No, it doesn’t affect the mass. Or the inertia.

But it does mean that there is no atmospheric resistance to the small sideforce applied by the sail.

A very small sideforce exerted over a period of time would produce a very small deflection.

But that would be all that was needed.

G.A. Having watched TV re your suggestion regarding a Solar Sail, can you explain just how that flimsy item could deflect an Asteroid travelling at a very high speed, not being sarcastic, but just how do you think that would be of use?

It may be travelling very quickly, but it’s doing so in a vacuum.

Newton’s Third, mate….. 😀

There’s more mileage in attempting to deflect an incoming asteriod that trying to destroy it completely.

If done early enough, you wouldn’t need to apply a huge amount of force so a solar sail – or even a coat of white paint on the sunward side – would be enough to do the trick.

The hard part is to detect the asteroid in the first place, of course.

This was probably the first time I saw it.

In 2003…… 😎

I doubt that anyone in HMRC would write a letter like that, but as a scam letter it is extremely funny.:D

Seen it before.

It’s a chain e-mail and, as such, a load of festering old cobblers.

Still funny, mind you. 🙂