Yesterday the Jet Propulsion Laboratory formally announced the launch dates chosen for Curiosity, the next generation Mars rover also known as. Of course, once the launch date slipped from October 2009, it was always known that the next launch opportunity would not come until late in 2011 with the next alignment of Earth and Mars. But this announcement marks the first time I've seen actual dates put on the launch period, most importantly the first possible launch date, November 25, 2011. Which is the Friday following Thanksgiving. Planetary alignments seem to love making us all work over holidays!
The actual launch period will go from November 25 to December 18, 2011. Launch within that period will result in a Mars landing between August 6 and August 20, 2012. This is a relatively short cruise period, and it apparently results in a landing geometry such that Curiosity will not have direct-to-Earth communication capability during landing. Which sounds a bit scary except that this was apparently a consequence of making sure that Curiosity would be in direct communication with both Mars Odyssey andthroughout entry, descent, and landing, and, moreover, Odyssey will have direct communication with Earth throughout the same period. What this means is that there will be a "bent-pipe" relay from Curiosity, to Odyssey, directly on to Earth, giving mission controllers telemetry from Curiosity very nearly as quickly as though it were coming direct from the rover, plus it will be at Odyssey's high-gain antenna's data rate of 8 or more kbps as opposed to Curiosity's low-gain antenna's data rate of 1 bit per second. This is how we got the data from Phoenix' landing, and it worked great then.
To read more, click here.