11.09.2021
SpaceX has been working for over seven years on the planning, production, and deployment of their Starlink satellite internet constellation, with the first regulatory filings dating back to 2014. Now heading into the latter stages of 2021, the company is nearing completion of the initial deployment for the constellation and preparing to expand its capabilities with extended geographic coverage and updated designs of both the satellites and ground equipment in their network.
The “Better Than Nothing Beta Test” of the service has already shipped 100,000 user terminals to customers in 15 countries as SpaceX continues refining network operations.
This first-generation Starlink constellation has orbital shells at four different inclinations. The initial shell at 53 degrees inclination, which is now nearing completion, initiates service to customers at latitudes up to around 55 degrees.
The version 1.0 satellites that were used to build this shell do not use laser inter-satellite links that will allow future Starlink satellites to communicate directly with each other. Therefore, the first shell requires a ground gateway station to be in the range of a satellite for it to provide service.
The remaining shells of the constellation will extend service to higher latitudes and expand the amount of bandwidth available to serve customers. The 70-degree shell will expand coverage to areas such as Alaska and Northern Europe, while the 97.6-degree shell will extend coverage over the polar regions. The 53.2-degree shell will greatly increase the number of satellites in view for customers in mid to low latitudes.
All of the satellites deployed in these future shells will have laser inter-satellite links that allow traffic to flow between satellites, allowing service when gateway stations are not in range and increasing transmission speed for long-distance traffic.
Launching Test Satellites and the Initial Shell
In total, SpaceX has included 1740 satellites from the Starlink program on 32 launches over the past three and a half years. In February 2018, they launched two early prototype satellites, named Tintin A and Tintin B. This was followed in May 2019 by a launch of 60 prototypes that were much closer to the operational model.
In November 2019, SpaceX launched the first batch of operational satellites into the initial shell of the constellation at 53 degrees inclination. Through May 2021, they completed 28 launches into this shell with 1665 satellites.
SpaceX has also launched a total of 13 satellites into Sun-Synchronous Orbit (SSO) as part of the first two Transporter rideshare missions in 2021. These are part of the 97.6-degree shell of the constellation. These satellites carried laser inter-satellite links and may have been used for testing as SpaceX matured that technology.
Status of the First Orbital Shell
The filling of the initial shell of the constellation has been a dynamic process that is now nearing completion. This shell is authorized to contain 1584 satellites, with 22 satellites in each of 72 evenly spaced planes. SpaceX is currently configuring each plane to have 18 active satellites with four slots for spares.
The 1296 slots for active satellites in the shell are nearly full, with only about 10 slots remaining open. The 288 slots for spare satellites are less full, with about 150 slots still open. Individual planes have anywhere from zero to four spares at the moment, with approximately two spares on average.
There are still about 100 satellites drifting into position or raising into their operational orbit. With about 50 of the satellites launched into this shell having already deorbited and several dozen more seemingly in the process of lowering their altitudes for deorbiting, SpaceX may end up with slightly under 1584 active satellites left in the shell out of the 1655 spacecraft that were launched.
As SpaceX prepares to launch the rest of the constellation, teams are readying launches from both Cape Canaveral, Florida, and Vandenberg, California to populate the different shells. This year, the number of remaining Starlink launches may be small as SpaceX still has around ten other missions to launch in 2021.
The 70-degree shell will be populated with Falcon 9 launches from Space Launch Complex 4 East (SLC-4E) at Vandenberg Space Force Base. The first launch is targeted to lift off no earlier than September 13.
The 97.6-degree and 53.2-degree shells will be launching from the Florida launch sites at Kennedy Space Center and Cape Canaveral Space Force Station. The date for the next Starlink launch from Florida is not currently known.
SpaceX has changed the naming convention for these future Starlink launches. The initial deployment used the format Starlink v1.0 L1 through Starlink v1.0 L28. The upcoming launch from Vandenberg is called Starlink Group 2-1. The designations for the next launches from Florida are not yet known.
Starlink Ground Infrastructure
SpaceX continues to iterate on hardware and software designs for all parts of their network as they operate their service in Beta Test mode. An end date for the Beta has not yet been announced.
At the Satellite 2021 Conference, as reported by Space News, SpaceX CFO Bret Johnsen said that SpaceX is currently making 5,000 user terminals a week and intends to increase production to “multiples of that” when the new user terminal design is introduced later in the year.
In April 2021, at the Satellite 2021 LEO Digital Forum, SpaceX President Gwynne Shotwell said that user terminal costs had dropped from an initial $3000 to a little less than half of that, with the new version 2 user terminals introduced at that time saving a couple hundred dollars on each unit. At the recent Space Symposium, she said that the cost will drop in half again with the introduction of the new user terminal design later this year.
Even with the cost savings, this new design is likely more expensive than the $500 that SpaceX charges customers for the hardware. Ms. Shotwell said that they hope to halve the price of the terminals again in the next year.
Quelle: NS