#^Launch Preview: GPS, Progress, and Starlink missions to launch during busy week
Seven missions, four countries, and five launch vehicles make the week of April 20 one of the more diverse on the 2026 manifest. GPS III SV10 carries the week’s most technically significant payload in its first-ever GPS laser communications demonstration, while South Korea’s ADD vehicle attempts its first complete four-stage orbital flight. Rocket Lab pulls double duty with missions from both hemispheres, SpaceX sustains its relentless Starlink cadence with two SSO deployments from Vandenberg, and Russia closes the week with another steady Progress resupply run to the International Space Station.
Falcon 9 | GPS III SV10The week opens with Falcon 9 launching the tenth and final satellite in the first-generation GPS III contract. Launch is scheduled for Tuesday, April 21, at 2:53 AM EDT (06:53 UTC) from Space Launch Complex 40 (SLC-40) at the Cape Canaveral Space Force Station in Florida. The 15-minute launch window closes at 3:08 AM EDT (07:08 UTC). Falcon booster B1095 is supporting this mission on its seventh flight, having previously launched six Starlink missions. The booster will land atop SpaceX’s
Just Read the Instructions downrange in the Atlantic.
GPS III SV10, nicknamed “Hedy Lamarr” after the Austrian-American actress whose 1941 frequency-hopping patent laid the groundwork for modern secure wireless communications, marks the closeout of a Lockheed Martin procurement program that began in 2008. SV10 has had a complicated path to the pad, bouncing between Falcon 9 and the United Launch Alliance’s (ULA) Vulcan twice due to Vulcan readiness concerns and the subsequent USSF-87 anomaly before landing back on Falcon 9. Construction of the satellite was completed in February 2023 and has been in storage since.
Beyond closing out the GPS III baseline constellation, SV10 carries something none of its predecessors did: a Tesat-Spacecom SCOT80 optical communications terminal. The demonstration will be the first laser communications test from a GPS satellite at medium Earth orbit, with the SCOT80 capable of data rates up to 100 Gbps. The long-term goal is optical crosslinks that allow the entire GPS constellation to be updated simultaneously from a single ground station, replacing the current radio-frequency architecture.
Electron | BubblesRocket Lab’s first mission of the week will see an Electron rocket lift off from Launch Complex 2 (LC-2) at NASA’s Wallops Flight Facility on Virginia’s eastern shore. The payload for “Bubbles” has not been disclosed ahead of launch, which is not uncommon for missions flying from Wallops, given the facility’s strong ties to government and national security customers. The rocket will fly east from LC-2 on a suborbital trajectory, with a five-hour window opening at 8:00 PM EDT (00:00 UTC) on Tuesday, April 21.
Electron is a two-stage small-lift launch vehicle standing 18 m tall, capable of delivering 320 kg to low-Earth orbit (LEO). Since its debut in 2017, the vehicle has become one of the most frequently flown small orbital rockets in the world. This will be Electron’s 86th mission overall and its seventh of 2026.
Falcon 9 | Starlink Group 17-14A Falcon 9 is scheduled to launch from Space Launch Complex 4 East (SLC-4E) at Vandenberg Space Force Base in California with a batch of 25 Starlink v2 Mini satellites heading to a Sun-synchronous orbit (SSO) as part of the Group 17 shell. Launch is scheduled for Wednesday, April 22, at 7:00 PM PDT (02:00 UTC on April 23), with the four-hour launch window extending to 11:00 PM PDT (06:00 UTC on April 23). SSO Starlink deployments provide coverage at high latitudes, supplementing the standard mid-inclination shells and extending reliable service to polar and near-polar regions.
The Starlink satellites before deployment in orbit. (Credit: SpaceX)
The mission will fly on booster B1100, making its fifth flight with a planned landing on the droneship
Of Course I Still Love You in the Pacific. B1100 debuted in November 2025 on a Starlink mission from Vandenberg, and has since supported the NROL-105 and two Starlink missions. The 32-day turnaround between its fourth and fifth flights continues a reliable reflight cadence for one of SpaceX’s newer boosters.
This will be Falcon 9’s 632nd mission overall and its 49th of 2026.
Electron/Curie | Kakushin RisingRocket Lab’s Electron is scheduled to launch an orbital rideshare mission from the Māhia Peninsula, carrying eight Japanese university and research institute satellites, at 02:09 UTC on Thursday, April 22. All eight satellites are part of the Japanese Aerospace Exploration Agency’s (JAXA) Innovative Satellite Technology Demonstration program, and were originally manifested on the Japanese Epsilon-S rocket as the RAISE-4 payload. However, persistent test-firing failures grounded that vehicle and prompted JAXA to turn to Rocket Lab as a replacement. Exolaunch is providing EXOpod NOVA deployment hardware for satellite deployments in orbit.
The eight satellites cover a broad range of research disciplines. WASEDA-SAT-ZERO-II, FSI-SAT2, MAGNARO-II, and KOSEN-2R are all re-flights of satellites lost on the RAISE-3 mission in October 2022. The remaining four — OrigamiSat-2 featuring a deployable origami-folded high-gain antenna; Mono-Nikko, with in-orbit battery health monitoring; ARICA-2 hosting gamma-ray burst detection) instruments; and PRELUDE, capable of ionospheric VLF signal collection for earthquake precursor research — are all new.
We're days away from flying our 2nd dedicated launch for @JAXA_en with "Kakushin Rising".
Payload integration and encap at LC-1 is complete for the mission's 8x spacecraft incl:
Educational small satellites
An ocean-monitoring satellite
A demonstration sat for… pic.twitter.com/nCu3l9nCv3
— Rocket Lab (@RocketLab) April 20, 2026
Electron will fly in its three-stage Electron/Curie configuration for the precision SSO insertion required by the mission. This will be Electron’s 87th mission overall and its eighth of 2026.
Chang Zheng 2D | Unknown PayloadA Chinese Aerospace Science and Technology Corporation (CASC) Chang Zheng 2D (CZ-2D) is scheduled to launch a currently-unknown payload from Launch Complex 3 (LC-3) at the Xichang Satellite Launch Center on Friday, April 24. Liftoff is scheduled toward the beginning of a 21-minute launch window, at 06:30 UTC.
The CZ-2D was first launched in 1992 and has completed 102 missions to date. Standing 40.77 m tall and 3.35 m wide, the rocket’s two stages — powered by toxic hypergolic fuels — are capable of lofting 3,500 kg to LEO and 1,200 kg to a geostationary transfer orbit. This mission will mark the third CZ-2D mission of 2026.
ADD Solid-Fuel SLV | Demo FlightOne of the more significant milestones of the week is South Korea’s Agency for Defense Development (ADD) making the first full-configuration orbital demonstration of its solid-fuel small satellite launch vehicle. The vehicle, known informally by the Korean acronym GYUB, is a four-stage rocket consisting of three solid-fuel stages and a liquid-fueled post-boost stage, designed to deliver small military payloads, primarily synthetic-aperture radar reconnaissance satellites, to SSO.
GYUB is scheduled to launch on its demonstration mission on Saturday, April 25, at 05:00 UTC, with the four-hour launch window extending to 09:00 UTC. The rocket will launch from one of ADD’s offshore launch platforms near Jeju Island, South Korea. GYUB will follow a southeastern trajectory out of South Korea to LEO.
The developmental path to this point has been methodical. Two suborbital test flights using only the lower stages occurred in March and December 2022. The first orbital attempt, launched on Dec. 4, 2023, used an incomplete three-stage configuration and successfully placed a 100 kg SAR satellite, designated Doory-Sat and built by Hanwha Systems, into a 650 km orbit. That mission deliberately omitted the second stage of the final vehicle. This demo flight will be the first time the complete four-stage vehicle has attempted an orbital insertion, with a target capacity of approximately 500 kg to LEO.
Sea-based launch provides South Korea with greater flexibility in azimuth selection than a comparable land-based pad, and it removes populated-overflight concerns from the downrange trajectory. Note that the vehicle name used here is provisional; South Korea has not released an official designation for the system. This will be the vehicle’s second overall mission and its first of 2026.
Soyuz 2.1a | Progress MS-34Russia’s Progress MS-34 cargo mission to the International Space Station (ISS) is scheduled to launch on Saturday, April 25, at 10:21 UTC. The Soyuz 2.1a rocket will lift off from Site 31/6 at the Baikonur Cosmodrome, the same pad that resumed operations in March 2026 following major repair work necessitated by the Soyuz MS-28 pad anomaly in late 2025. Progress MS-33, which launched on March 22, 2026, carrying over 2.5 tons of supplies, was the first mission to use the restored pad.
Progress MS-34 will carry approximately 7,280 kg of cargo at liftoff in the standard pressurized and propellant configuration. A typical Progress MS mission delivers food, water, fuel for orbital reboost, oxygen, and spare hardware. The spacecraft docks automatically using the Kurs rendezvous system and generally executes a two-day rendezvous with the Station after launch.
Progress MS-34 undergoes pre-launch processing. (Credit: Roscosmos)
The Progress spacecraft traces its lineage to 1978 and has been the backbone of ISS and Soviet-era station resupply for nearly five decades. Progress MS-34 will be the 187th flight in the long-running program. The MS-series variant, introduced in 2015, brought updated communications, improved docking sensors, and an extended autonomous flight capability compared to the earlier Progress M series. Soyuz 2.1a entered service in 2004 and has become the standard carrier for both Progress and Soyuz crewed missions, replacing the analog Soyuz-FG for crewed flights in 2020. This will be Soyuz 2.1a’s 90th mission and its third of 2026.
Falcon 9 | Starlink Group 17-16The final launch of the week will see Falcon 9 deliver another batch of 25 Starlink v2 Mini satellites to SSO from SLC-4E at Vandenberg on Sunday, April 26, at 7:00 AM PDT (14:00 UTC). The four-hour launch window closes at 11:00 AM PDT (18:00 UTC), with Falcon 9 following a southern trajectory out of California.
The mission will fly on booster B1088, a veteran vehicle making its 15th flight with a planned recovery on
Of Course I Still Love You. B1088 first flew in January 2024 and has been one of SpaceX’s more consistently cycled boosters throughout its career, flying. The 39-day turnaround between its 14th and 15th flights reflects the current operational tempo at Vandenberg.
This will be Falcon 9’s 633rd mission overall and its 50th of 2026, marking the 95th orbital launch attempt worldwide this year.
(Lead image: Falcon 9 launches from Florida. Credit: Julia Bergeron for NSF)
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Launch Preview: GPS, Progress, and Starlink missions to launch during busy week appeared first on
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