Spaceflight’s 64-satellite rideshare mission set to last five hours

EDITOR’S NOTE: The Falcon 9 rocket launched on the SSO-A mission at 10:34:05 a.m. PST (1:34:05 p.m. EST; 1834:05 GMT) Monday, Dec. 3. Story updated at 4 p.m. EST (2100 GMT) to remove ROSE 1 from the payload list.

Video credit: Spaceflight Industries

When SpaceX’s Falcon 9 rocket takes off with 64 small satellites — a payload cache representing 34 customers in 17 nations — it will be just the first act in a nearly five-hour sequence to deftly deploy each of the spacecraft, which range in size from a Rubik’s cube to a refrigerator.

The mission, dubbed SSO-A SmallSat Express, is set for takeoff aboard a Falcon 9 rocket at 10:31:47 a.m. PST (1:31:47 p.m. EST; 1831:47 GMT) Monday from Space Launch Complex 4-East at Vandenberg Air Force Base, California.

The multi-payload rideshare mission was arranged by Spaceflight, based near Seattle, a company specializing in securing launch bookings for small satellite operators. Spaceflight has booked satellite launches on Antares, Dnepr, PSLV, Soyuz and Vega missions, but the company had never purchased the full capacity of a rocket until announcing plans for the SSO-A rideshare mission in 2015.

Most of the satellites on the SSO-A mission, which includes 15 microsatellites and 49 CubeSats, were installed on two free flyers at Spaceflight’s facility in Auburn, Washington, officials said.

The deployment structure developed by Spaceflight consists of two hubs — an upper and a lower free flyer — carrying satellites and CubeSat dispensers. Both free flyers will separate from the Falcon 9 rocket once it enters a polar, sun-synchronous orbit around 357 miles (575 kilometers) above Earth.

Curt Blake, president of Spaceflight, said the free flyers are based on Spaceflight’s Sherpa space tug, which the company intended to launch for the first time on a Falcon 9 flight shared with Taiwan’s Formosat 5 Earth observation satellite. But delays in Formosat 5’s launch, caused in part by a Falcon 9 rocket explosion on a launch pad in 2016, prompted Spaceflight to cancel the mission and find alternative launch opportunities for the smallsats reserved on the Sherpa flight.

The Formosat 5 mission finally launched last August.

“Generically, we call it the Sherpa,” Blake said of the SSO-A mission in an interview with Spaceflight Now earlier this month. “But it is actually more than one hub. There’s an upper free flyer and and a lower free flyer. There’s a lot of spacecraft on each of those. It’s kind of a combination stack.”

A few of the larger passengers on the SSO-A mission were shipped directly to the Falcon 9 launch site at Vandenberg Air Force Base in California, where technicians mated them to the free flyers. In addition to the 60 payloads on the free flyers, four microsatellites are attached directly to the Falcon 9’s second stage, which will command their separation after arriving in orbit.

The entire payload stack riding into orbit on the Falcon 9 rocket will weigh around 4 metric tons — nearly 9,000 pounds — at the time of launch. Once in orbit around minutes after liftoff, the Sherpa modules, or free flyers, will release from the rocket and begin releasing the smallsats.

Both free flyers and the four microsatellites attached to the Falcon 9’s second stage will be released in orbit by the T+plus 43-minute point in the mission, but Spaceflight’s deployment module’s themselves will continue on, using on-board batteries to power avionics and issue commands to release the separate the 60 spacecraft.

The exact sequence of the satellite separation maneuvers is considered proprietary by Spaceflight, but mission managers said each deployment is timed approximately every six minutes, with the final payload set for separation around 4 hours, 45 minutes, after liftoff — approximately 3:16 p.m. PST (6:16 p.m. EST; 2316 GMT), assuming an on-time launch.

It will then take another hour or so for Spaceflight to confirm all the satellites have separated, once the free flyers pass over a ground station to enable communications. There are no on-board cameras on either free flyer, according to Spaceflight, but SpaceX’s Falcon 9 rocket is expected to provide live video as the Sherpa modules separate from the rocket, and show release of the four microsatellites directly attached to the second stage.

“We’ve developed a deployment sequence that’s based off a high-fidelity analysis that we did specifically to make sure our customers don’t collide into each other upon deployment, so we’re taking our time,” said Jeff Roberts, Spaceflight’s SSO-A mission manager, said in an interview with Spaceflight Now. “We make sure that we phase that to maximize the distance in separation between all of our customers.”

That should help the U.S. military, which tracks objects in orbit, more quickly identify the satellites released on the SSO-A mission, an issue that has caused headaches in the past.

The free flyers will operate as independent spacecraft themselves, with their own computers, electronics and batteries.

“We refer to them as free flyers because that’s exactly what they are. There is no propulsion system on-board. They just simply hold all the avionics and the dispensers to command deployment,” Roberts said.

The upper free flyer is based on a commonly-used secondary payload adapter — known as an ESPA ring — built by Moog. The lower free flyer is Spaceflight’s own design, according to Roberts.

The free flyer modules will unfurl drag sails after the satellite deployments to help bring the dispensers back into Earth’s atmosphere.

Spaceflight has not publicly released an accounting of all 64 payloads aboard the SSO-A rideshare mission, citing non-disclosure agreements signed with the company’s customers. But Roberts said the company provided a list to the Federal Communications Commission to obtain launch licenses for the mission, and Spaceflight submitted the separation sequence, information on spacecraft sizes, and points-of-contact for each payload to the U.S. military’s Combined Space Operations Center, which is charged with cataloguing, tracking and identifying all objects launched into orbit.

Roberts said some concerns about the mission are unfounded, such as worries about the difficulty of tracking the smallsats launched on the SSO-A mission to ensure they don’t create a space debris hazard. “Our engineering team has put a ton of effort into every aspect of this mission,” he said.

Some customers have disclosed their payloads are on the SSO-A launch.

Planet is one of major commercial customers on the mission. Two of its SkySat microsatellites and three Dove CubeSats — debuting new camera and telescope designs — set to join its large fleet of more than 100 Earth-imaging craft in orbit. Planet is also sponsoring the launch of two CubeSats from the Georgia Institute of Technology and the University of Colorado in Boulder’s Laboratory for Atmospheric and Space Physics.

Three missions funded by the U.S. military are among the largest spacecraft slated to fly on the SSO-A mission. They are STPSat 5, a microsatellite from the Air Force’s Space Test Program which hosts five experiments, the eXCITe spacecraft funded by the Defense Advanced Research Projects Agency — DARPA — and the FalconSat 6 satellite built by students at the Air Force Academy.

There is also a microsatellite from DLR, the German Aerospace Center, named Eu:CROPIS, which carries tomato seeds to monitor how they germinate and grow in reduced gravity. The spacecraft will slowly spin during its mission, simulating gravity conditions on the moon and Mars.

One of the CubeSats on the Falcon 9 launch — Elysium Star 2 — carries cremated human remains, and another was conceived as an art project and sponsored by the Los Angeles County Museum of Art to honor Robert Lawrence, an African American astronaut was selected for the U.S. Air Force’s Manned Orbiting Laboratory program. A bust of Lawrence, who died in 1967 before he flew in space, is on the Enoch CubeSat.

“To honor the astronaut’s legacy, (Tavares) Strachan created a 24-karat gold canopic jar with a bust of Lawrence,” the Los Angeles County Museum of Art wrote on a page deviated to the mission. “The canopic jar nods to a practice employed by the ancient Egyptians to protect and preserve organs of the deceased for use in the afterlife. The canopic jar was blessed at a Shinto shrine in Fukuoka, Japan, and was recognized as a container for Lawrence’s soul.”

Spaceflight considers future rideshare plans after SSO-A’s ‘complex undertaking’

Blake told Spaceflight Now the SSO-A mission turned out to be a complex undertaking.

“To fill, or to make profitable buying a rocket the size of Falcon 9, you have to aggregate a lot of small spacecraft,” he said. “Just understanding what kind of timescale that’s going to take and how many satellites you’re going to have to aggregate to hit that one point in time — that’s one lesson — just understanding where that is, and how difficult it is.

“The second one is during the timeframe as you’re getting ready, different customers have different potential issues,” he added. “Some float through as easy as can be. Others may have difficulties along the way. We’ve had to move different customers around on the stack. That means that you really need to have an ability to configure and reconfigure the stack, (and) the electronics that go into the deployments.”

Seven CubeSats dropped off the SSO-A mission since August because they were not ready for launch, or had difficulty obtaining regulatory approval.

The record number of satellites launched on a single rocket is 104, set by an Indian PSLV mission last year. Some of those payloads were customers of Spaceflight, but not all. The SSO-A mission will set a record for the most satellites aboard a U.S. launcher.

Blake said Spaceflight has no immediate plans to buy another dedicated Falcon 9 launch. The economical and logistical sweet spot for rideshares may be using a smaller rocket, he said.

“We’re making sure to see how this one goes, and getting all the lessons learned out of it, before turning our attention to doing another one this large,” Blake said. “Having said that, we’re actively looking at different ones on medium-sized launch vehicles.

The company has agreements for future smallsat rideshare launches on Arianespace’s Vega rocket, Rocket Lab’s Electron, and Virgin Orbit’s air-dropped LauncherOne vehicle — all significantly smaller, and less expensive, than a Falcon 9, which currently sells for around $50 million to $60 million per flight.

“We know about aggregating a number of payloads onto small launch vehicles,” Blake said. “You can think of those as dedicated missions as well, where we’ve got five or 10 different spacecraft on a smaller launch vehicle, 30 or 40 on a medium-sized launch vehicle. The thing we’ll take time to sort out is how it goes on a large launch vehicle like this.”

Here’s a list of most of the payloads on the SSO-A mission, based on the best public information available.

  • Audacy Zero – Audacy – USA
  • BlackHawk – ViaSat – USA
  • BRIO – SpaceQuest- USA
  • THEA – SpaceQuest – USA
  • Capella 1 – Capella Space – USA
  • Landmapper BC-4 – Astro Digital – USA
  • CSIM-FD – LASP/University of Colorado – USA
  • Flock 3s Doves (3 spacecraft) – Planet – USA
  • SkySat 14, 15 (2 spacecraft) – Planet – USA
  • Elysium Star 2 – Elysium Space – USA
  • Enoch – Los Angeles County Museum of Art – USA
  • eXCITe/SeeMe – Novawurks & DARPA – USA
  • FalconSat 6 – U.S. Air Force Academy – USA
  • Fox 1C – AMSAT – USA
  • BlackSky Global 2 – BlackSky Global – USA
  • Hawk A, B, C (3 spacecraft) – HawkEye 360 – USA
  • ICE-Cap – U.S. Navy – USA
  • IRVINE02 – Irvine CubeSat STEM Program – USA
  • MinXSS 2 – LASP/University of Colorado – USA
  • ORS 7A, 7B Polar Scouts – Operationally Responsive Space, Dept. of Defense, Dept. of Homeland Security – USA
  • Orbital Reflector – OR Productions & Nevada Museum of Art – USA
  • RANGE A, B (2 spacecraft) – Georgia Tech – USA
  • SeaHawk 1 – University of North Carolina at Wilmington – USA
  • SpaceBEE 5, 6, 7 (3 spacecraft) – Swarm Technologies – USA
  • STPSat 5 – U.S. Air Force Space Test Program – USA
  • WeissSat 1 – Weiss School – USA
  • Centauri II – Fleet Space Technologies – Australia
  • RAAF M1 – University of New South Wales – Australia
  • SIRION Pathfinder 2 – Sirion Global – Australia
  • ITASAT – Instituto Tecnológico de Aeronáutica – Brazil
  • ICEYE X2 – ICEYE – Finland
  • Suomi 100 – Aalto University Science and Technology – Finland
  • Eu:CROPIS – DLR, German Aerospace Center – Germany
  • MOVE-II – Technische Universität München – Germany
  • ExseedSat-1 – Exseed Space – India
  • Eaglet-1 – OHB Italia S.p.A./Italian Ministry of Defense – Italy
  • ESEO – ESA & SITAEL – Italy
  • JY1-Sat – Crown Prince Foundation – Jordan
  • KazSciSat-1 – Ghalam LLP – Kazakhstan
  • KazSTSAT – Ghalam LLP – Kazakhstan
  • Hiber 2 – Hiber/Innovative Solutions in Space – Netherlands
  • PW-Sat 2 – Warsaw University of Technology – Poland
  • K2SAT – Korean Air Force Academy – South Korea
  • NEXTSat-1 – Korea Advanced Institute of Science and Technology – South Korea
  • SNUGLITE – Seoul National University – South Korea
  • SNUSAT-2 – Seoul National University – South Korea
  • VisionCube – Korea Aerospace University – South Korea
  • AISTECHSAT 2 – Aistech – Spain
  • Astrocast 0.1 – Astrocast – Switzerland
  • KNACKSAT – King Mongkut’s University of Technology North Bangkok – Thailand
  • VESTA – Honeywell Aerospace/SSTL/exactEarth Ltd. – UK/Canada

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