Atlas 5 with MSL payload sits atop the launch pad. Credit Pat Corkery, United Launch Alliance.

In just under 3 hours time an Atlas 5 is scheduled to blast off from Launch Complex 41 at Cape Canaveral, Florida. This rocket will carry the Mars Science Laboratory into space on its way to the Red Planet on a two year mission to examine the surface of the planet to determine if it was possible that there was the capabilities to support carbon based life at any time in the past.

The launch is targeted for 10:02 EST which is 15:02 GMT but has a 1 hour 43 minute launch window.  This means that it is possible that the rocket could launch any time between 10:02 and 11:45 and still be able to set off on the correct path to reach Mars.

The United States Air Force, who provide support facilities for the launches at Cape Canaveral, are predicting a 70% chance that there will be favourable weather conditions for the launch.  Should the launch be scrubbed today for any reason the next opportunity to launch would be tomorrow with the same weather patterns.  If the launch should fall back to Monday then the weather will change to a 70% chance of violating launch criteria.

Wired4Space will be covering the launch from the top of the VAB at Kennedy Space Center just over 4 miles from the launch pad.  With 3 hours to go the weather looks fine and clear on the Florida Space Coast.

Good Luck Atlas 5, Best Wishes NASA, Bon Voyage MSL and Curiosity!