Electron Launches the Eighth StriX Satellite for Synspective

Rocket Lab's "Eight Days A Week" mission delivered its eighth StriX satellite to orbit for Synspective, and it was also the moment the 250th satellite was deployed from Electron. The dedicated launch lifted off from Launch Complex 1 at Mahia, New Zealand, at 7:10 a.m. New Zealand time (18:10 UTC), and ended in what mission control called a nominal final orbit. It was Rocket Lab's fifth launch of the year and the 84th Electron mission overall.

A mission named for a count

The name nods to the Beatles song and to the eighth StriX satellite Rocket Lab has flown for the Japanese company Synspective. Electron has been the sole launcher for Synspective's constellation since the first mission with them in 2020. After this launch, another 19 missions are booked to deliver the rest of the constellation to orbit before 2030, and the broadcast noted that viewers would keep seeing owl-themed mission patches on Electron's fairing.

StriX satellites carry synthetic aperture radar (SAR). Rather than capturing light like a camera, SAR uses radio waves; the satellite measures differences in the waves bouncing back from mountains, trees and buildings to build a detailed picture. The data is used for urban development planning, construction and infrastructure monitoring, and disaster response. A Synspective representative said the satellites can operate at any time of day, at night and in rain, which makes them useful in floods and typhoons, where the company's disaster damage assessment solution can quickly estimate affected areas for local agencies.

A custom fairing

The fairing looked different from usual because it was a bespoke "Arrowhead" design, shaped to fit the wide body of the StriX satellite. Rocket Lab has used it across several Synspective launches. The broadcast also mentioned a longer custom fairing used on a recent HASTE launch from Wallops Island, Virginia, for taller payloads or dual-stack missions.

Electron on the pad

Electron stands about 18 m tall on the pad and carries up to 300 kg to low Earth orbit. Its structure and propellant tanks are carbon composite. Its Rutherford engines use 3D-printed combustion chambers, injectors, main propellant valves and pumps, and the pumps are driven by electric motors powered by batteries. On top of the second stage sits the kick stage, an orbital transfer vehicle with its own 3D-printed Curie engine, able to adjust altitude and inclination and deploy multiple satellites into different orbits. Launch was from pad B of Launch Complex 1.

Countdown

Weather was green with an 80% chance of launch, and there was one attempt that day. Launch director Taylor Moore ran the go, no-go poll, which was completed at T minus 11 minutes, 22 seconds. Terminal count auto sequence began at T minus 10 minutes. Around T minus 2 minutes the auto sequence was locked and flight computer checks confirmed green; the vehicle was on internal power, the autonomous flight termination system (AFTS) was green and enabled, and the stage one and two tanks were pressurized.

Flight

Electron lifted off at the end of a 10-second count and began its pitch over. At 43 seconds it was climbing nominally, and it cleared max Q, the point of greatest aerodynamic pressure, with the nine first-stage Rutherford engines throttling back up. The vehicle was travelling at more than 2,000 km per hour.

Main engine cutoff (MECO) was confirmed, followed by stage separation and second stage ignition at more than 90 km altitude. The second stage then passed 7,800 km per hour, and the fairing was jettisoned. With a speed above 8,500 km per hour, the stage had 74% of its kerosene and 74% of its LOX remaining at one check.

Around six and a half minutes into flight came the battery hot swap, a feature the broadcast described as unique to Electron and its Rutherford engines. Because the second stage engine burns longer than the first, its pumps need more power, so the worn battery packs are ejected and replaced with a fresh set. Mission control confirmed battery jettison and a successful hot swap.

Second engine cutoff (SECO) came in less than 10 minutes from launch, followed by separation of the kick stage into an elliptical transfer orbit, where it coasted around the Earth.

Deployment

After the coast, the Curie engine fired to circularize the orbit for a 573 km low Earth orbit deployment. Mission control confirmed Curie cutoff, then payload separation, then a nominal final orbit. The broadcast called it mission success and wished Synspective well with satellite commissioning. The next Electron launch, announced for a couple of days later from the neighbouring pad at Launch Complex 1, was a dedicated mission for the European Space Agency.