WASHINGTON – On June 25, a SpaceX Falcon Heavy rocket launched with the final spacecraft in a series of geostationary weather satellites that also feature some firsts.
The Falcon Heavy launched from Kennedy Space Center’s Launch Complex 39A at 5:26 p.m. Eastern Time, 10 minutes into a two-hour window because launch control found favorable weather despite the previous day’s weather forecasts predicting only a 30 percent chance of acceptable weather.
The rocket’s payload, the GOES-U weather satellite, is scheduled to be deployed from the Falcon Heavy’s second stage four and a half hours after launch, after the stage completes a sequence of three burns to place the satellite into geostationary transfer orbit.
GOES-U is the fourth and final satellite in the Geostationary Operational Environmental Satellite (GOES) R-series of satellites built by Lockheed Martin for the National Oceanic and Atmospheric Administration. The spacecraft, which will be renamed GOES-19 in geostationary orbit, will undergo an in-orbit commissioning and then be deployed to 75 degrees East in GEO to succeed GOES-16 as the operational GOES-East satellite.
The satellite carries a suite of Earth and space science instruments similar to those on the three previous GOES-R satellites, but also has the Compact Coronagraph (CCOR) instrument for observing the Sun. CCOR will monitor the solar corona for flares and coronal mass ejections that affect space weather, replacing the nearly 30-year-old Solar and Heliospheric Observatory spacecraft.
Meteorologists say observations from the first three GOES-R weather satellites have significantly improved weather forecasting. “The GOES-R series of satellites have been a game changer for us,” said Ken Graham, director of the National Weather Service, at a briefing on June 24. “Since the series was first launched in 2016, the latest GOES series has enabled new and improved forecasts, warnings and services that help save lives and protect property.”
New features in the GOES-R series include a lightning mapper. “I think it took a while for meteorologists to realize what this could do,” said Pam Sullivan, director of the GOES-R program at NOAA, at another briefing on June 24. She said the lightning data allows meteorologists to better assess the severity of a storm and issue warnings accordingly. “The main thing I hear from meteorologists is that they have more confidence in a forecast.”
NOAA is working on a new generation of geostationary weather satellites called GeoXO, scheduled for launch in 2032. NASA, which is assisting NOAA in developing weather satellites, has contracted Lockheed Martin to build the satellites and BAE Systems (formerly Ball Aerospace) to build sonar and ocean color instruments for the spacecraft.
GOES-U “is the bridge that connects today’s geostationary satellite technology with the technology of tomorrow, which promises to be even more sophisticated and impactful,” said Steve Volz, deputy director of NOAA’s GeoXO satellite and information services.
The launch also marked the first time NOAA launched a GOES weather satellite on a SpaceX rocket. The three previous GOES-R satellites were all launched on United Launch Alliance Atlas 5 rockets, but NASA awarded SpaceX a $152.5 million contract for a Falcon Heavy launch of GOES-U in September 2021. ULA withdrew its bid because Atlas rockets were no longer available.
One advantage of the Falcon Heavy is the extra power it provides. Julianna Scheiman, NASA science mission manager at SpaceX, said at a pre-launch briefing on June 24 that the extra power is measured in terms of the delta V, or change in velocity, that the spacecraft itself must provide to reach its final geostationary orbit.
The mission requirements were a delta V of no more than 987 meters per second, while Falcon Heavy will launch GOES-U into a transfer orbit with a delta V of 566 meters per second. “A smaller number means less energy is required for the spacecraft to reach that orbit, which can save fuel,” she said.
These fuel savings will result in a longer operational life for GOES-U. The spacecraft is designed to last 15 years, said NOAA’s Sullivan. “With the additional capabilities that Falcon Heavy gives us, we expect a fuel life of over 20 years.”
The start was on the 10th.th for the Falcon Heavy overall and the second commissioned by NASA, after the Psyche asteroid mission, which launched in October 2023. Another Falcon Heavy will launch the Europa Clipper mission for NASA this October.