SpaceX will make another attempt to launch the Deep Space Climate Observatory (DSCOVR) satellite tonight, its fourth since Sunday. The initial attempt was called off because of a failure in the Air Force's tracking radar; the weather was too bad on the other occasions. Tonight's launch is scheduled for 6:03PM ET.

This mission was supposed to serve as the second test of the company's reusable Falcon 9, but SpaceX just announced that's no longer the case. The weather in the Atlantic Ocean is causing swells up to three stories high, and one of the autonomous drone ship's engines isn't functioning. Instead, SpaceX will perform a "soft landing," which means the rocket will splash down in the ocean and won't likely be recovered.

The company first attempted to land the Falcon 9 on the 300-by-100-foot barge back in January, but the rocket exploded on impact. SpaceX's next scheduled Falcon 9 launch is February 27th, when it will deliver two satellites to space for French company Eutelsat.

DSCOVR, meanwhile, will head for a spot almost a million miles away known as "Lagrange point 1," or "L1." L1 is a stable place between the gravities of Earth and the Sun that's also outside of our planet's magnetic environment. DSCOVR will use those characteristics of L1 to its advantage while it observes Earth for 110 days. During that time it will survey solar winds, which are capable of disrupting power grids, aviation, and GPS.

You can watch tonight's launch above on NASA TV. If SpaceX doesn't launch today, the company is in for a delay. The position of the Moon over the next eight days will interfere with DSCOVR's trajectory — so the next try will have to wait until at least February 20th.