The two Gravity Recovery and Climate Experiment (GRACE) satellites will observe the earth's changing climate by monitoring changes in glaciers and sea levels.
Following the launch earlier on Tuesday from Vandenberg Air Force Base, NASA confirmed that the two satellites are in communication with its ground station in Antarctica.
It's Falcon 9's 54th trip to space since 2012.
The launch had been delayed by two days due to a slight issue preparing the Falcon 9 rocket.
Now in orbit, the satellites will monitor the earth's water cycle and study the movement of water masses across the planet.
They replace two previous GRACE satellites that operated until October 2017.
Last week NASA published a study using 14 years of GRACE data which found that the Earth's dry areas are getting drier due to human water management and climate change.
According to NASA,the mission is set to fly for a minimum of five years.
Jim Bridenstine, administrator of NASA said: "I'm grateful to the many scientists, technicians and engineers who have worked years to make the GRACEFO mission possible. I look forward to seeing many more Earth science missions as NASA administrator."
Falcon 9 is a two-stage rocket designed and manufactured by Elon Musk's SpaceX for the reliable and safe transport of satellites and the Dragon spacecraft into orbit.
