A new comet from the oort cloud, >10 km wide, has been discovered that is doing a flyby of Mars in October of 2014. The current orbit is rather uncertain, but it is probably passing within 100,000 km and the max likelihood is ~35,000 km. There is a tiny but non-negligable chance this thing could actually hit the red planet, in which case we would get to witness an event on the same order of magnitude as the K-T event that killed off the non-avian dinosaurs! (and lose everything we have on the surface of the planet and in orbit.)

I, for one, hope it hits. That would not be a once in a lifetime opportunity. That would be a ONCE IN THE HISTORY OF HOMINID LIFE opportunity! We would get to observe a large impact on a terrestrial body as it happened and watch the aftermath as it played out for decades!

As is, the most likely situation though is one in which we get to closely sample and observe the comet with everything we have in orbit around Mars. The orbit will be nailed down better in a few months when the comet comes out from the other side of the sun.

And to quote myself towards the end of the last open thread:

I don't know if this has been brought up around here before, but the B612 foundation is planning to launch an infrared space telescope into a venus-like orbit around 2017. It will be able to detect nearly every earth-crossing rock larger than 150 meters wide, and a significant fraction down to a few at 30ish meters. The infrared optics looking outwards makes it much easier to see the warm rocks against the black of space without interference from the sun and would quickly increase the number of known near earth objects by two orders of magnitude. This is exactly the mission I've been wishing / occasionally agitating for NASA to get off their behinds and do for five years. They've got the contract with Ball Aerospace to build the spacecraft and plan to launch on a Falcon 9 rocket. And they accept donations.