A SpaceX Falcon Heavy rocket is set to carry the satellite into orbit from NASA's Kennedy Space Center in Florida, though weather so far appears unfavorable for the two-hour launch window opening at 5:16 pm (2016 GMT).
The GOES-U (Geostationary Operational Environmental Satellite U) mission is a collaboration between the space agency NASA and the National Oceanic and Atmospheric Agency (NOAA).
It will be the fourth and final in the GOES-R series of satellites that have tracked hurricanes and tornadoes, monitored climate and sea surface temperature, air quality and even meteor detections since 2016.
Orbiting 22,236 miles (35,785 kilometers) above the equator, the satellites match the speed of Earth's rotation in order to hold their positions over specific regions and provide continuous coverage.
They "are an indispensable tool for protecting the United States and the one billion people who live and work in the Americas," Pam Sullivan, of NOAA said in a press conference.
GOES-U is the first of the four to include a coronagraph, called the Compact Coronagraph-1 (CCOR-1). Coronagraphs block the Sun's disk and allow observation of its outermost layer, called the corona.
"That allows us to observe large explosions off the sun, called coronal mass ejections that can hurtle billions of tons of matter at millions of miles per hour towards Earth," said Elsayed Talaat, in charge of space weather observations at NOAA.
The ejections, known as CMEs, can disrupt Earth's magnetic field, causing satellites, energy infrastructure, and navigation systems to go down. Collecting space weather data allows authorities to issue warnings one to four days in advance.
In early May, the planet experienced its first level 5 geomagnetic storm in two decades, the highest rating on the scale, which unleashed spectacular auroras worldwide.
With the new coronagraph, the speed and direction of this event could have been better understood from the start, said Talaat.
Major disruptions weren't felt, but some farmers "reported being unable to plant their crops because the precision GPS relied upon by their equipment had malfunctioned," he said.
For the first time, the United States will have a coronagraph observing the solar corona almost continuously, with the CCOR-1 taking readings every 30 minutes.
Currently, such observations are received with a delay of up to eight hours. They are carried out by a satellite launched in 1995, which should cease operating within two years.
"Once operational CCOR-1 will mark a new chapter in space weather observations," said Talaat.
"Although the sun is no more active than in previous generations, our society has changed, and we are more sensitive than ever to the sun's changing mood."
