Not that SpaceX will necessarily mind. This is its first launch involving Inmarsat, so losing a rocket may be worthwhile if it helps secure a long-term customer. And of course, it's particularly important for Inmarsat itself -- the satellite will help fill out its Global Xpress internet service for commercial aircraft and ships. If you have a faster connection the next time you're flying overseas, you might chalk it up to this mission.

Just don't base your schedule around this blast-off. SpaceX periodically has to scrub launches due to weather or last-minute glitches, and it has a backup scheduled for a similar time on May 16th if things go awry. Although conditions are looking good so far, there's always the chance of a surprise delay.

Update: Success! SpaceX's Falcon 9 launch carrying a payload of Inmarsat satellites launched from the company's LC-39A complex at Kennedy in Florida on Monday. It has completed its first stage separation and initiated its second stage burn to reach its intended orbit.