NASA is getting ready for the launch of its next mission called the GRACE-FO (Gravity Recovery and Climate Experiment Follow-On) mission. The main aim of the mission will be to observe and map the changes occurring in water and ice in all parts of the world by identifying the gravity variations in different places.

The mission consists of two similar space crafts that will be orbiting the Earth in tandem. Both the satellites are currently scheduled to launch atop the Falcon 9 rocket of SpaceX from California’s Vandenberg Air Force base on 19th May at 4:03 pm EDT. After it has deployed the GRACE-FO satellite about 490 kilometers above the Earth, the rocket will be delivering five communication satellites of Iridium Next into a bit higher orbit.

As the name indicates, the GRACE-FO is a follow-up the mission of the real GRACE mission which was used to map our planet’s gravity field from the year 2002 to 2017. Both missions were jointly carried out by the GFZ German Research Center for Geosciences and NASA. After the huge success of the first GRACE mission that worked beyond its lifespan of 5 years, the batteries of the spaceship gave up to time, and the mission ended. But with the launch of these two satellites of the latest technology researchers hope to continue their mission from where it ended. During the GRACE mission of 15 years, scientists have found extreme changes in different parts of the world. The most significant observations of all were the rising of the sea levels due to the melting of polar ice caps.

When the ice melts, no matter whether it forms a part of the ocean or seeps down to the soil, it changes the overall mass is distributed on the Earth. And when there is a change in the mass of the Earth, the gravity field also changes. It is by measuring those changes that the GRACE mission scan track the water cycle and the effect of climate on oceans, sea ice, glaciers, groundwater and even the moisture content in the atmosphere.

Both the spacecraft will be flying approximately about 220 kilometers apart and will be sending microwave signals to detect the gravitational changes. When they pass over a place with increased or decreased gravity, the distance between the spacecraft will change a bit to map that area. In actual words, the water movement will be mapped by measuring the weight of the water.