SpaceX launched their third mission of 2021 and the first of many planned Smallsat Rideshare Program missions, which are designed by the company to give small satellite operators the chance to launch together as a way to reduce cost on regularly scheduled flights to frequently used orbits.
The flight, called Transporter-1, lifted off with a record number of satellites on Sunday, January 24 at 10:00 EST (15:00 UTC) at the opening of a 22 minute launch window from Space Launch Complex 40 (SLC-40) in Florida.
Onboard were 143 satellites and hosted payloads from dozens of nations. The sheer number of payloads/satellites was well above the limit needed to break both the U.S. and world records for most satellites launched on a single mission.
SpaceX’s previous record is 64 satellites on the SSO-A mission in December 2018, a flight that featured Spaceflight Industries’ Sherpa satellite dispenser. Since then, Spaceflight has developed a new set of Sherpas as a part of their Sherpa-NG (Next Generation) program.
The first is the Sherpa-FX, named “Go Now.” Sherpa-FX, which will be used on Transporter-1, is a free-flying non-propulsive transfer stage capable of multiple satellite deployments across a period of time as well as support for hosted payload operations in orbit.
The other two Sherpas are the -LTC (“Go Fast”) and -LTE (“Go Far”). The -LTC is a free-flying transfer stage that will use a high-thrust bi-propellant green propulsion system while the -LTE version will use an ion Hall thruster powered by Xenon propellant. Both are targeting first flights in the second half of 2021.
For Transporter-1, Sherpa-FX carries three hosted payloads and deployed 13 of the mission’s small satellites. The remaining satellites were integrated to either independent dispensers mounted to the Falcon 9 or grouped together on other dispenser platforms that, like Sherpa-FX, separated first from the Falcon 9 and then deployed their satellites.
Before that happened, Falcon 9 placed the entire group into a Sun-synchronous orbit of 550 km inclined 97.59 degrees to the equator.
To reach this orbit, SpaceX would normally launch from Vandenberg Air Force Base, California, in a south-southwesterly direction. Instead, this mission lifted off from Florida and used the polar launch corridor that allows a Falcon 9 to fly south-southeast between Florida and The Bahamas and then, once the second stage separates, perform a “dogleg” maneuver to the south-southwest to achieve the mission’s needed inclination.
This allows polar launches from Florida to occur over open water and not violate land overflight restrictions during the initial powered phase of ascent to orbit.
This benefits SpaceX in allowing the company to launch Sun-synchronous and polar missions from Florida and forgo having to move Falcon 9 first stages back and forth across the country.
Transporter-1 was the second mission since 1969 to use this polar corridor route from Florida. SAOCOM-1B in late-August 2020 was the first.
Falcon 9 B1058-5, sporting a fresh pair of fairing halves, is poised for the next attempt to launch the #Transporter1 mission. While weather scrubbed today's attempt, OCISLY was basking in the sun downrange. Window opens at 10:00 am ET tomorrow, 1/24. #SpaceX pic.twitter.com/IzND1VS0BA
— Julia Bergeron (@julia_bergeron) January 23, 2021
While first reported to use the same payload fairings that protected the SAOCOM-1B satellite, SpaceX appears to have tested a new fairing design on Transporter-1 that relocates the vents to keep them above the waterline when the fairings splashdown for recovery.
After encapsulation for flight, the group was brought to SLC-40 and mated to the top of the Falcon 9 second stage before the entire assembly, including first stage booster B1058-5, was moved out to the pad and taken vertical for launch.
B1058-5 previously supported the Demo-2 mission of Crew Dragon Endeavour with NASA astronauts Bob Behnken and Doug Hurley in May 2020, ANASIS-II in July 2020, Starlink v1.0 L12 in October 2020, and SpaceX CRS-21 with the first Cargo Dragon 2 mission to the Station in December 2020.
With its last flight just 49 days prior, B1058-5 fell short of the all-time record turnaround that was set earlier this week on January 20 by B1051-8 at just 38 days between flights.
After firing for the first 2 minutes 28 seconds of flight, B1058-5 separated from the second stage and headed for a landing and recovery on the Autonomous Spaceport Drone Ship Of Course I Still Love You positioned 553 km south of Cape Canaveral between the coast of Cuba and The Bahamas.
Recovery of the payload fairings will also be attempted for refurbishment and reuse. Both GO Ms. Tree and GO Ms. Chief have been deployed to the fairing recovery zone for this mission.
After reaching orbit, the full payload deployment sequence from Falcon 9 is:
| Time since launch (hr:min:sec) | Event |
| 00:58:59 | 36 SuperDoves begin deployment |
| 00:59:00 | Kepler port deployment of 17 satellites begins |
| 00:59:09 | NASA mission with 3 satellites deploys |
| 01:08:19 | Eyries-1 with 9 payloads deploys |
| 01:08:44 | EXOport-2 with 28 satellites deploys |
| 01:13:58 | Capella-3 deploys |
| 01:14:10 | EXOport-1 with 2 satellites deploys |
| 01:14:23 | iQPs-2 satellite deploys |
| 01:15:38 | Capella-4 deploys |
| 01:16:10 | Sherpa-FX with 13 satellites deploys |
| 01:16:28 | D-Orbit’s Pulse carrier with 20 satellites deploys |
| 01:31:10 | Starlink satellites deploy |
Of the satellites on Transporter-1, one is the Pathfinder Technology Demonstrator (PTD)-1, owned and operated by NASA Ames Research Center, which will test the truly green HYDROS® water electrolysis thruster from Tethers Unlimited, Inc. – as well as a variety of new CubeSat subsystems that aim to provide enhancements to these small and effective spacecraft.
Conversely, three Hawk 2 satellites will be part of a global intelligent radio frequency constellation used to monitor transportation across land, sea, and air to assist with emergencies and the crucial role of detecting and locating emergency beacons and improving response times in life-threatening scenarios.
The ARCE (Articulated Reconnaissance and Communication Expedition) satellites will likewise test communication capabilities, but in space. This three satellite grouping from the University of South Florida will test inter-satellite networked communications.
In addition to communications, numerous satellites on the flight will use Synthetic Aperture Radar, or SAR, to perform various Earth observation missions and tests. SAR technology allows satellites to “see” through clouds and weather formations, permitting continuous monitoring of Earth’s surface no matter the atmospheric conditions.
Additionally, the Sherpa-FX payload dispenser will host Celestis 17, a passive payload containing cremated human remains. Also on Sherpa-FX is another passive payload: the Extremely Low-Resource Optical Identifier (ELROI) experiment that will use LED lights to improve orbital identifications and debris mitigation.
A GNSS Navigation and Occultation Measurement Satellite (GNOMES), owned and operated by PlanetIQ, will be the second satellite of a planned constellation to provide radio occlusion data for weather forecasting, climate research, and space weather monitoring.
The Student’s Oxygen Measurements Project 2b (SOMP 2) satellite, meanwhile, will measure atomic oxygen in the upper atmosphere.
Likewise, IDEASSat, one of two Taiwanese satellites on the mission, will monitor the thermal, chemical, and electro-dynamic structure of Earth’s ionosphere in a search for plasma that can cause disruptions to satellite and radio communications. The second Taiwanese satellite, YUSAT, will monitor ground traffic as well as improve maritime navigation safety.
Also on the flight are eight Lemur-2 satellites for Spire’s global maritime constellation, 36 Planet SuperDoves, 10 Starlink satellites, and dozens of other payloads.
These Starlinks will be the first of the operational constellation launched into a polar orbit and will maneuver up to 770 km after initial deployment, allowing SpaceX to achieve better/earlier coverage in the polar regions.
Beyond this mission, SpaceX is set to launch more Starlink missions in the coming weeks. One more Starlink flight is currently scheduled to launch on January 27 from LC-39A. More Starlink missions are planned for February as well.
Two more Transporter flights are also planned for this year, with Transporter-2 and Transporter-3 as early as June 2021 and December 2021, respectively.
Lead image: The Transporter-1 mission launches from SLC-40. Credit: |Stephen Marr