It was fourth time's the charm today as NOAA's Deep Space Climate Observatory (DSCOVR) lifted off from Space Launch Complex 40 at Cape Canaveral Air Force Station, Florida at 6:05 pm EST. The launch went without incident, placing the unmanned solar weather station into a parking orbit, but rough weather in the recovery area meant that the planned power landing attempt of the Falcon 9 booster had to be abandoned.
Today was the fourth launch attempt for DSCOVR. The first was aborted due to an avionics problem and the failure of a range safety radar, the second was abandoned because of fog, and the third due to strong high-altitude winds. Unfortunately, though the weather was acceptable for today's launch, rough seas were reported at the location of the drone barge where the Falcon 9 was scheduled to make its landing attempt. Waves three-storys high were encountered and SpaceX reported that only three of the barge's four station-keeping engines were functioning.
In a preflight tweet before the first launch attempt on Sunday, SpaceX founder and CEO Elon Musk said that the barge landing attempt would be much harder than previous ones because the booster was reentering the Earth's atmosphere at deep-space return velocity, resulting in twice the force and four times the temperature. However, he also said that this time the Falcon 9 was carrying a surplus of hydraulic fluid, the lack of which caused the failure of the hypersonic vanes that guide the booster during reentry and caused January's crash.
Despite abandoning the barge landing, SpaceX said in a statement that the booster would still make a soft water landing that would return valuable data. After separating from the second stage, the Falcon 9 first stage autonomously executed a series of engine burns, beginning with a "boostback" burn to set it on course for the landing site. This was followed by a supersonic retro propulsion burn to help slow it, then a final burn to slow it to 2 m/s (6.5 ft/s) as the landing legs deployed for a soft touchdown on the surface of the Atlantic Ocean. SpaceX says that the rocket was unlikely to survive the landing.
Today marked SpaceX's first deep space mission launch, which will see the DSCOVR spacecraft reaching an orbit of 1,241,000 x 187 km (771,000 x 301 mi) at an inclination of 37 degrees to the equator. The 570-kg (1,256-lb) DSCOVR, which was launched for the US Air Force in conjunction with NOAA and NASA. In 110 days, it will go on station at the Sun-Earth L1 Lagrangian point, 1,500,000 km (930,000 mi) from Earth, which is four times farther away than the Moon, The solar-powered craft is designed as a space weather station for keeping an eye on the Sun and giving Earth advanced warning of approaching solar flares that could disrupt communications and power grids.
The video below shows the launch – skip to 19:50 for blastoff.