A reason to go to Mars

Kevin Burgess wrote:

> Very interesting. Just how much NEA material is there?

"More than 5,000 near Earth objects, including 789 potentially hazardous
objects, have been identified so far. Johnson predicted that future
surveys will find at least 66,000 near Earth objects and 18,000
potentially hazardous objects."

That gives an idea of how many objects we're talking about; for a
typical size of an "object":

"Apophis was discovered in 2004 about 17 million miles from Earth on a
course that would overlap our planet's orbit in 2029 and return seven
years later. Observers said that the asteroid a massive boulder left
over from the birth of the solar system is about 1,000 feet wide and
weighs at least 50 million tons."

Cheers,
- Joe