Riding a light beam to Mars

Getting back however might be a problem. I guess it's called "DEEP-IN" because that's how the spacecraft will land on Mars.

The article says that a 100 Kg object can be sent to Mars in three days. At the average distance between Earth and Mars, that would be an average speed of nearly two million mph. Even at the closest distance ever recorded, thirty-five million miles, the craft's speed would average about a half million mph.

Unless the craft has massive engines (and fuel), it would seem that the craft would have to start slowing down about half way there (which, of course, means that the speed on the first half of the trip would have to be much greater). And with all that stopping power on board, the 100Kg limit is unworkable. So how are they going to slow the thing down?

This looks like another solution is search of a problem.

Cool, though.

_Howard wrote:

So how are they going to slow the thing down?

It's called "DEEP-IN".

Emphasis on the IN.

Light sails have some potential for interstellar travel. Braking at the destination just involves using the destination star's light, plus a little fancy manoeuvering. But for interplanetary travel it seems a bit far-fetched, to say the least.

Once again, scientifically illiterate writers writing for ostensibly scientific journals.

Low standards and all that. Contributes unfortunately to the general public ignorance of science.