Falcon 9 Transporter 2 launch
A SpaceX Falcon 9 lifts off June 30 on the Transporter-2 rideshare mission, with 88 satellites on board. Credit: SpaceX webcast

WASHINGTON — SpaceX launched 88 satellites on a Falcon 9 June 30 on the company’s second dedicated smallsat rideshare mission.

The Falcon 9 lifted off from Space Launch Complex 40 at Cape Canaveral Space Force Station at 3:31 p.m. Eastern, more than halfway into a nearly hourlong launch window because of weather. A launch attempt the day before was scrubbed when a private helicopter entered restricted airspace minutes before the scheduled liftoff.

Deployment of the payload of 88 satellites started nearly 58 minutes after liftoff, once the upper stage performed a second burn of its engine to place it into a sun-synchronous orbit at an altitude of nearly 550 kilometers. The satellites, from a variety of government and commercial customers, were released over half an hour.

The mission, named Transporter-2 by SpaceX, was the company’s second dedicated smallsat rideshare mission, after the Transporter-1 mission in January. The earlier flight carried 143 satellites, but SpaceX said the total payload mass for Transporter-2 was greater than that of Transporter-1. The company did not disclose specific payload mass figures for either mission.

SpaceX established its smallsat rideshare program nearly two years ago, offering low-cost launches on dedicated Falcon 9 missions like Transporter-2 as well as on launches of its Starlink satellites. It has attracted significant interest from both companies and government agencies.

The Transporter-2 payload manifest featured synthetic aperture radar (SAR) satellites from three competing companies: Capella, Iceye and Umbra. HawkEye 360 and Kleos, two companies deploying constellations to perform radio-frequency tracking, each had satellites on this mission, as did PlanetIQ and Spire, which collect GPS radio occultation data for use in weather forecasting.

Other commercial customers included Astrocast and Swarm, which are each developing internet-of-things constellations, and Satellogic, which has a multi-launch agreement with SpaceX for launching its imaging satellites. SpaceX flew three of its own Starlink satellites on the launch, which will join 10 Starlink satellites launched into polar orbit on Transporter-1.

The Pentagon’s Space Development Agency (SDA) had four satellites on Transporter-2. Two Mandrake-2 satellites — originally intended to launch on Transporter-1 before being damaged in prelaunch processing — feature optical crosslinks and will be used to test technologies for future low Earth orbit military satellite. Two cubesats built by General Atomics will also test optical communications between satellites and with drones. SDA has a fifth payload on Loft Orbital’s YAM-3 satellite.

NASA flew two smallsats on Transporter-2, including a pathfinder for a cubesat constellation called TROPICS, for Time-Resolved Observations of Precipitation structure and storm Intensity with a Constellation of Smallsats. TROPICS Pathfinder is identical to the six TROPICS satellites that Astra will launch on its Rocket 3 small launch vehicle in 2022 and will enable full testing of the satellite design in advance of the deployment of the constellation.

Many of the customers worked with launch services providers such as D-Orbit, Exolaunch and Spaceflight. That included two Sherpa tugs from Spaceflight on this launch, one of which has electric propulsion from Apollo Fusion.

Launch cadence and reusability

Transporter-2 was SpaceX’s 20th Falcon 9 mission of the year, with six months yet to go. In only two years has SpaceX conducted more orbital launches: 21 in 2018 and 26 in 2020. The company is on track to shatter the record set last year, even with an anticipated slowdown of launches in July and August.

A key factor in that high launch cadence is reusability. The Falcon 9 booster used for Transporter-2 was making its eighth flight, concluding with a landing at Cape Canaveral’s Landing Zone 1. Its first launch was exactly one year ago, when it launched a GPS 3 satellite, and was also used for launching Turksat 5A and five Starlink missions before Transporter-2. Other Falcon 9 boosters have flown up to 10 times.

While SpaceX previously set a goal of 10 flights per booster, company officials have in recent months suggested those boosters could fly more than 10 times. “We’ve got boosters now that have flown 10 times, and some that are slated to fly 20 or possibly 30 times,” Elon Musk, founder and chief executive of SpaceX, said in a June 29 appearance at the Mobile World Congress.

“With Falcon 9, we’ve achieved I think the most efficient reusability of any rocket to date,” he said, but added that SpaceX will take reusability “to another level” with its Starship vehicle. That vehicle, whose first orbital launch Musk now says will take place in the “next few months,” is intended to be reflown without any significant refurbishment, like an airliner.

“The Holy Grail for rocketry is rapidly reusable reliable rockets,” he said.

Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews. He earned a Ph.D. in planetary sciences from the Massachusetts Institute of Technology and a bachelor’s degree with honors in geophysics and planetary science...