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Rocket Lab launched a South Korean Earth-observation satellite and new NASA solar-sailing tech to orbit this evening (April 23).
The agency's Advanced Composite Solar Sail System, or ACS3 for short, was one of two payloads that lifted off atop a Rocket Lab Electron vehicle from New Zealand today at 6:33 p.m. EDT (2233 GMT; 10:33 a.m. on April 24 New Zealand time).
The Rocket Lab mission turned out to be the second half of a spaceflight doubleheader; SpaceX launched 23 of its Starlink internet satellites from Florida just 16 minutes earlier, at 6:17 p.m. EDT (2217 GMT).
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Solar sails harness the subtle push of sunlight, using it to propel probes through space much as seagoing ships capture the wind here on Earth. Because solar sailing is efficient and requires no fuel, many exploration advocates have high hopes for this relatively novel propulsion strategy.
A few solar sailing missions have already flown, including Japan's Ikaros spacecraft and the Planetary Society's LightSail 2. ACS3 aims to develop the technology further.
"The mission plans to test the deployment of new composite booms that will unfurl the solar sail to measure approximately 30 feet [9 meters] per side, or about the size of a small apartment in total," Rocket Lab wrote in a mission description.
"Flight data obtained during the demonstration will be used for designing future larger-scale composite solar sail systems for space weather early-warning satellites, asteroid and other small body reconnaissance missions, and missions to observe the polar regions of the sun," the company added.
ACS3 was the secondary payload on today's mission, which Rocket Lab called "Beginning of the Swarm." The main passenger was NEONSAT-1, an Earth-observation satellite developed by the the Satellite Technology Research Center at the Korea Advanced Institute of Science and Technology.
NEONSAT-1 will use a high-resolution camera and artificial intelligence tech to monitor and track natural disasters along the Korean coastline, according to Rocket Lab. Other NEONSAT spacecraft will launch in 2026 and 2027 to add to the constellation, which explains the "Beginning of the Swarm" moniker.
The two satellites headed to different orbits. The Electron deployed NEONSAT-1 323 miles (520 kilometers) above Earth about 50 minutes after liftoff, then deposited ACS3 at an altitude of 620 miles (1,000 km) 55 minutes later as planned.
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"Beginning of the Swarm" was Rocket Lab's fifth orbital launch of 2024 and its 47th overall. All but four of the company's liftoffs to date have occurred from its New Zealand site, on the North Island's Mahia Peninsula; the others have lifted off from NASA's Wallops Flight Facility in Virginia.
Rocket Lab is working to make the 59-foot-tall (18-meter-tall) Electron's first stage reusable. The company has recovered boosters from the sea on multiple prior missions and is planning to refly one of them on an upcoming launch. But there were no recovery activities on "Beginning of the Swarm."
Editor's note: This story was updated at 6:53 p.m. EDT on April 23 with news of a successful liftoff, then again at 8:22 p.m. EDT with news of satellite deployment.