SpaceX is about to launch a batch of 54 Starlink web satellites – Starlink Group 5-1 – into low Earth orbit (LEO) this Wednesday, Dec. 28, 2022. Liftoff is scheduled to happen at 4:40 AM EST (09:40 UTC) from Area Launch Complicated 40 (SLC-40) on the Cape Canaveral Area Drive Station (CCSFS) in Florida.
Starlink Group 5-1 is the primary flight devoted to the second era (Gen 2) Starlink constellation. Earlier flights have been filling the primary era (Gen 1) Starlink constellation, which SpaceX started launching in Might 2019.
The official climate forecast from the forty fifth Climate Squadron at CCSFS requires a higher than 90% likelihood of favorable climate situations on the first launch day and a 90% likelihood of favorable climate situations on the following day. For extra danger standards, the forecast exhibits a average danger of unhealthy climate situations for booster restoration on the first launch day.
The Falcon 9 countdown for Wednesday’s launch will comply with the now conventional 35-minute-long automated propellant load sequence. At T-3 seconds the engine controller will ship the ignition command to all 9 Merlin 1D engines on the primary stage which can ramp as much as full energy in round 2.8 seconds.
The rocket will likely be then launched at T0 by the launch clamps and start its climb into orbit. The primary stage for this mission, B1062, is flying for its eleventh time and would be the fifth booster to succeed in this mark.
The booster will hearth its engines for the two-and-a-half minute ascent into close to area, after which B1062 will shut down its engines and separate from the second stage. After separation, it’ll try a touchdown on SpaceX’s Autonomous Spaceport Drone Ship A Shortfall Of Gravitas which is positioned 660 km downrange east of The Bahamas.
For this mission, the Falcon 9 launch trajectory goes southeast and performing a dogleg maneuver round The Bahamas. SpaceX used comparable launch trajectories earlier this yr through the winter months to keep away from the harsher climate and sea state situations off the mid-Atlantic coast and is returning to this launch profile for the present winter season.
After stage separation, the second stage will ignite its single Merlin 1D Vacuum (MVacD) engine for roughly six minutes to inject the satellites into LEO. The fairing halves will separate shortly after MVacD ignition and can carry out a parachute-assisted splashdown within the ocean. They are going to be retrieved from the water by SpaceX’s multi-purpose restoration vessel Doug.
The goal insertion orbit for this mission is 212 by 338 km at 43 levels inclination. The second stage will use a single burn of its MVacD engine to place the satellites into the goal orbit. Deployment will happen at round T+19 minutes and shortly after the second stage will carry out one other burn to deorbit and safely deplete over the southwest Indian Ocean.
This mission is launching 54 Starlink satellites for the 530 km altitude, 43-degree inclination shell of Starlink’s Gen 2 constellation. That is the primary time SpaceX is launching to this new constellation and it’s doing so utilizing Falcon 9.
In August 2021, SpaceX introduced plans to the Federal Communications Fee (FCC) to both use Falcon 9 or Starship to deploy satellites into Starlink Gen 2. However then, in January 2022, the corporate introduced they might use solely Starship as they thought it was going to be prepared for launches as quickly as March of this yr.
Nevertheless, technical delays in readying Starship for its first orbital flight meant that the corporate needed to revisit its plans and in August 2022 it introduced to the FCC that they might now launch into Starlink Gen 2 utilizing each Starship and Falcon 9.
The document detailed that “whereas SpaceX will use technically similar satellites on each rockets, the bodily constructions will likely be tailor-made to fulfill the bodily dimensions of the rockets on which they are going to be launched.”
This indicated that SpaceX meant to make use of downsized satellites that will be capable to match inside Falcon 9’s payload fairing. It was then confirmed by Elon Musk throughout an occasion with T-Cellular later that month. The CEO of the corporate referred to those as Starlink v2 “Mini” however not like the doc, the place it doesn’t specify any situations to launching Starlink v2 satellites on Falcon 9, he stated this is able to solely be within the occasion Starship had been to be delayed even additional.
Map with touchdown places for Group 5 launches (highlighted) and the touchdown places of prior southeast Starlink launches which went to a mid-inclination orbit.
Indications that this launch specifically was associated to Starlink Gen 2 got here in late October 2022 when SpaceX filed a allow with the FCC requesting authorization to speak with the Falcon 9 rocket throughout launch and touchdown for this mission. These permits usually embody the touchdown location of the Falcon 9 booster, whether or not it’s a drone ship or in any other case.
The touchdown coordinates on the permits for this and subsequent Group 5 missions indicated not solely that they meant to make use of a southeast launch trajectory once more similar to they did earlier this yr, but in addition that the Group 5 launches wouldn’t be to polar orbit as beforehand thought.
Starlink’s Gen 1 constellation consists of 5 orbital shells at 4 completely different inclinations. The preliminary Gen 1 launch marketing campaign to fill the 53.2-degree shell used mission numbers of the shape LNN, as much as the L28 launch in Might of 2021.
In September 2021, SpaceX began utilizing the Group X-Y designation for his or her Starlink missions. It was understood at the moment that the primary quantity, X, could be the shell to which the satellites are being deployed whereas the second, Y, indicated the mission quantity (however not essentially the order of launch). Up to now SpaceX has launched missions to 3 of these shells utilizing “Group X-Y” mission designations.
It was straightforward then to assume that Group 5 launches could be going into the remaining orbital shell which is one with Solar-synchronous orbits – a sort of polar orbit. Nevertheless, based mostly on the touchdown coordinates on the FCC permits, it was clear that the Group 5 missions wouldn’t be going into that orbital shell and due to this fact it needed to be associated to one thing new. Specifically, these touchdown coordinates indicated that Group 5 launches had been going right into a mid-inclination orbit.
Desk with the orbital shells SpaceX has requested for Starlink Gen 2. The FCC granted partial approval in December 2022 to deploy 7500 Starlink Gen 2 satellites into the 33, 43, and 53-degree orbital shells within the decrease 500km altitude area.
In early December 2022, SpaceX obtained a license that solely authorized the deployment of 7500 Starlink Gen 2 satellites into the 33, 43, and 53-degree inclination orbital shells within the decrease 500 km altitude area. Given SpaceX’s intentions to begin deployment of those satellites not solely with Starship but in addition with Falcon 9, it was a matter of time for them to begin launching Starlink Gen 2 satellites on the latter.
Just some weeks later, SpaceX submitted a request for a Particular Momentary Authority (STA) to the FCC to function VHF telemetry, monitoring, and command beacons on Starlink Gen 2 satellites. This STA confirmed SpaceX was monitoring Wednesday’s launch as the primary of the Starlink Gen 2 constellation.
Nevertheless, questions stay as to what particular {hardware} is included in these satellites. Earlier paperwork by SpaceX to the FCC detailed as much as three completely different configurations for Starlink Gen 2 satellites. One, dubbed F9-1, could be the identical measurement and mass as Starlink v1.5 satellites that the corporate is already launching and could be launching on Falcon 9.
One other configuration that would launch on Falcon 9, dubbed F9-2, could be virtually double the dimensions, double the variety of photo voltaic arrays, and practically 3 times as huge because the F9-1 kind of satellite tv for pc. The doc additionally included the size for the third Starlink Gen 2 satellite tv for pc configuration which SpaceX plans to launch on Starship.
Desk from an October 2022 doc to the FCC the place SpaceX particulars the completely different doable configurations of Starlink Gen 2 satellites the corporate was planning to make use of.
The variety of satellites flying on Starlink Group 5-1 suggests this mission is flying the F9-1 satellite tv for pc configuration which might permit them to make use of {hardware} and processes just like launching Starlink v1.5 satellites underneath the Gen 1 constellation.
SpaceX has already utilized for 3 extra Group 5 launches within the subsequent couple of months and sources point out they’ll begin launching Group 6 missions as early as February, additionally headed to Starlink’s Gen 2 constellation. It could look like the Group X-Y mission designation is used for launches of each the Gen 1 and Gen 2 Starlink constellations.
Wednesday’s launch will likely be SpaceX’s sixtieth launch of the yr and the second-to-last mission for the corporate in 2022. This launch will likely be adopted by one other from Vandenberg later within the week lofting the primary EROS-C3 satellite tv for pc. If each launch earlier than the tip of the month, SpaceX would beat their goal of 60 launches this yr as they put together for a busy 2023 the place the corporate is concentrating on 100 launches.
(Lead picture: A Falcon 9 utilizing B1062 at SLC-40 making ready for the June 2022 launch of Nilesat-301. Credit score: Stephen Marr for NSF)
