NASA’s SunRISE Solar-Radio Mission Shifts to SpaceX Falcon Heavy

NASA’s SunRISE (Sun Radio Interferometer Space Experiment) was slated for a summer 2026 launch aboard United Launch Alliance’s Vulcan Centaur. After a February 2026 solid-rocket-booster (SRB) nozzle burn-through on the fourth Vulcan flight and the United States Space Force’s subsequent pause on all national-security launches using Vulcan, NASA moved the mission to a SpaceX Falcon Heavy rideshare sponsored by the Space Force’s Space Systems Command. The new launch window is now expected in 2027, pending an updated schedule.

The Register UKULA's Manifest Keeps Shrinking As NASA Moves SunRISE To SpaceXUnited Launch Alliance loses NASA's SunRISE mission to SpaceX

The February anomaly occurred during a USSF-87 mission, where a GEM-63XL SRB nozzle failed, prompting the Space Force to halt Vulcan launches until an investigation and corrective actions are completed. This pause forced the fourth adjustment of the National Security Space Launch (NSSL) manifest to accommodate SunRISE, joining earlier shifts that moved GPS III-8 and other payloads to alternative rockets.

ULA's Manifest Keeps Shrinking As NASA Moves SunRISE To SpaceX

• NASA – mission manager and primary developer.

United Launch Alliance loses NASA's SunRISE mission to SpaceX

• United Launch Alliance (ULA) – original launch provider for Vulcan Centaur.

ULA's Manifest Keeps Shrinking As NASA Moves SunRISE To SpaceX

• SpaceX – current launch provider operating Falcon Heavy.

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• U.S. Space Force, Space Systems Command (SSC) – rideshare sponsor that can reassign payload contracts.

United Launch Alliance loses NASA's SunRISE mission to SpaceX

• Sue Lepri – SunRISE principal investigator, University of Michigan.

United Launch Alliance loses NASA's SunRISE mission to SpaceX

• Space Dynamics Laboratory (Utah State University, Logan) – assembly and testing site for the six SmallSats.

United Launch Alliance loses NASA's SunRISE mission to SpaceX

• Six SmallSats, each roughly the size of a toaster oven, completed construction in 2023 and final testing in early 2026.

ULA's Manifest Keeps Shrinking As NASA Moves SunRISE To SpaceX

• Satellites will operate ~6 miles (10 km) apart, each deploying four 10-foot (2.5 m) radio antennas.

ULA's Manifest Keeps Shrinking As NASA Moves SunRISE To SpaceX

• The formation will sit just above geosynchronous orbit (~22,000 miles altitude).

ULA's Manifest Keeps Shrinking As NASA Moves SunRISE To SpaceX

• The mission will function as a single giant radio telescope to capture solar radio bursts.

ULA's Manifest Keeps Shrinking As NASA Moves SunRISE To SpaceX

SunRISE will deliver unprecedented detail on radio bursts tied to solar particle storms, enhancing space-weather forecasting that protects satellites and crewed missions. Its observations will complement existing heliophysics assets such as NASA’s STEREO, Parker Solar Probe, and the ESA-NASA Solar Orbiter partnership, expanding scientific understanding of how solar magnetic activity propagates through the solar system.

United Launch Alliance loses NASA's SunRISE mission to SpaceXULA's Manifest Keeps Shrinking As NASA Moves SunRISE To SpaceXThe Register UK

NASA indicated it “will share updated launch timing in the near future,” and described the spacecraft as “a single, giant radio telescope to capture in unprecedented detail data on the radio bursts associated with the Sun’s particle storms.” The Space Force’s SSC facilitated the rapid rideshare switch, though neither ULA nor SpaceX provided public comment on the change.

ULA's Manifest Keeps Shrinking As NASA Moves SunRISE To SpaceX

Industry observers note a “troubling pattern” of schedule risk, certification delays, and now a grounded Vulcan vehicle, suggesting reliability concerns for the launch system. The lack of official responses from ULA and SpaceX has been highlighted as a gap in transparency.

ULA's Manifest Keeps Shrinking As NASA Moves SunRISE To SpaceX

Sources differ on the anticipated launch timeframe: some state the mission will likely launch in 2027, while others maintain it remains “this year” with no specific date announced. No definitive schedule has been released, and details of the forthcoming Falcon Heavy rideshare slot remain undisclosed.

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• “will share updated launch timing in the near future,” — NASA spokesperson

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• “the six SmallSats will act as a single, giant radio telescope to capture in unprecedented detail data on the radio bursts associated with the Sun's particle storms.” — NASA description

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• “Solar radio bursts are triggered after vast quantities of energy stored in the Sun’s magnetic field accelerate solar particles to high speeds,” — Sue Lepri, SunRISE principal investigator

United Launch Alliance loses NASA's SunRISE mission to SpaceX

• “Tracking these events will not only help space agencies mitigate their damaging effects on astronauts and spacecraft but will also add new science to our growing knowledge base of how space weather is generated and propagates throughout the solar system.” — NASA statement

United Launch Alliance loses NASA's SunRISE mission to SpaceX