Update: The SpaceX team is running additional ground system checks, so the liftoff has been moved to 3:10 p.m. EDT.
After a slight delay, a used SpaceX Falcon 9 rocket is scheduled to make its second trip to space today (June 23) to orbit the first communications satellite for Bulgaria. The BulgariaSat-1 launch will mark the Falcon 9's second flight this year, and may kick off a double-header with a Sunday SpaceX launch as well.
You can watch the launch live online here at Space.com, courtesy of SpaceX.
The rocket with pre-flown booster is set to launch from Kennedy Space Center's historic Pad 39A during a window extending from 2:10 to 4:10 p.m. EDT (1810-2010 GMT). On Jan. 14, the company successfully launched and landed the booster while putting 10 communications satellites into low-Earth orbit for the Virginia-based company Iridium. This time, the booster will help loft Bulgaria's communications satellite before landing again.
If successful, this will mark SpaceX's 11th successful first-stage landing and the company's second time re-flying a previously used booster. SpaceX also reused a flown Dragon cargo capsule to bring supplies to the International Space Station earlier this month. SpaceX will attempt to land the booster on the “Of Course I Still Love You” droneship, which will be stationed in the Atlantic Ocean.
SpaceX has a second launch planned within 48 hours — on Sunday (June 25) a new Falcon 9 is set to launch another 10 satellites for Iridium, but across the country at the Vandenberg Air Force Base in California. The satellites will form part of the company's 70-satellite Iridium NEXT constellation. You will be able to watch that launch live on Space.com as well.
Editor's Note: This article has been updated to show that the spent booster will attempt to land on a drone ship, not on a ground-based landing pad as previously stated.
Email Sarah Lewin at slewin@space.com or follow her @SarahExplains. Follow us @Spacedotcom, Facebook and Google+. Original article on Space.com.