If conditions improve, the launch will be take place at 6:05 p.m. EST (2305 GMT) today – 10 February.
The mission will end with an ambitious rocket landing attempt on a floating platform in the Atlantic Ocean.
It is the second time the Deep Space Climate Observatory mission has been delayed after a radar malfunction on Sunday.
The $340 million DSCOVR mission is a partnership between NASA, NOAA and the US Air Force. As Space.com explains:
The spacecraft is designed to alert scientists 15 to 60 minutes before a potentially dangerous solar storm could impact Earth. Bad space weather can harm satellites in orbit and even disrupt power grids on the planet, potentially knocking out electricity for a wide swath of Earth. Early warning systems can help guard against those potentially harmful issues, experts have said.
DSCOVR will orbit at approximately 1.6 million kilometres from Earth, with enough fuel to last for five years.
The mission will be SpaceX’s second attempt in two months to land a rocket to prove reusable rocket technology is possible. The previous attempt failed when the rocket came in too fast, smashed into the platform and exploded.
You can watch the launch live on the mission website.