SpaceX Falcon 9 Full Thrust - Iridium-1 NEXT - Launching January 14, 2017
Screenshot from SpaceX - Iridium-1 NEXT with a clear ocean view and ready to go
Mission Rundown: SpaceX FT - Iridium-1 NEXT
Written: January 29, 2021
This time we got a big job to do
SpaceX is targeting the launch of Iridium-1 from Space Launch Complex 4E (SLC-4E) at Vandenberg Air Force Base in California. The instantaneous launch window is at 08:54:34 p.m. PST, or 17:54:34 UTC, on January 14.
SpaceX’s Falcon 9 rocket will deliver 10 satellites to low-Earth orbit for Iridium, a global leader in mobile voice and data satellite communications. This is the first set of 10 satellites in a series of 75 total satellites that SpaceX will launch for Iridium’s next generation global satellite constellation, Iridium® NEXT. The satellites will begin deployment about an hour after launch.
Iridium NEXT Constellation
The second-generation Iridium-NEXT satellites began to be deployed into the existing constellation in January 2017. Iridium Communications, the successor company to Iridium SSC, has ordered a total of 81 new satellites being built by Thales Alenia Space and Orbital ATK: 66 operational units, nine on-orbit spares, and six spares yet to be launched.
In August 2008, Iridium selected two companies — Lockheed Martin and Thales Alenia Space — to participate in the final phase of the procurement of the next-generation satellite constellation. The constellation provides L band data speeds of up to 128 kbit/s to mobile terminals, up to 1.5 Mbit/s to Iridium Pilot marine terminals, and high-speed Ka-band service of up to 8 Mbit/s to fixed/transportable terminals. The NEXT satellites incorporate a secondary payload for Aireon, a space-qualified ADS-B data receiver for use by air traffic control and, via FlightAware, by airlines. A tertiary payload on 58 satellites is a marine AIS ship-tracker receiver for Canadian company ExactEarth
As of 2009, the original plan had been to begin launching new satellites in 2014.
The design was completed by 2010, and Iridium stated that the existing constellation of satellites would remain operational until Iridium NEXT is fully operational, with many satellites expected to remain in service until the 2020s, while the NEXT satellites would have improved bandwidth. The new system was to be backward-compatible with the current system. In June 2010, the winner of the contract was announced as Thales Alenia Space, in a $2.1 billion deal underwritten by Compagnie Française d'Assurance pour le Commerce Extérieur. Iridium additionally stated that it expected to spend about $800 million to launch the satellites and upgrade some ground facilities.
The first ten Iridium NEXT satellites are stacked and encapsulated in the Falcon 9 fairing for launch from Vandenberg Air Force Base, CA, in early 2017 (image credit: Iridium)
Sunday Jan. 8, 2017 - 10:28:07 PST - 18:28:07 UTC - 1st launch attempt - 1 second window
Saturday Jan. 14, 2017 - 09:54:39 PST - 17:54:39 UTC - 2nd launch attempt - 33:28 early window
The eight Iridium NEXT launches go to following planes 1-6 on these dates and some of them either stay fixed in orbit or move to other neighboring orbit planes. These 6 plane orbits precede eastward and pass over VAFB about 330 seconds earlier every day.
SpaceX was contracted to launch all the Iridium NEXT satellites. All the Iridium NEXT launches have taken place using a Falcon 9 rocket launch from Vandenberg Air Force Base in California. Deployment of the constellation began in January 2017, with the launch of the first ten Iridium NEXT satellites to orbit plane 6, where 8 stayed and 2 shifted to orbit plane 5 in order to relive the oldest satellites.
Below is a picture of the assembly process of stacking two ESPA pipe sections, each of them mounted with 5 Iridium NEXT satellite vehicles. They will be deployed in the order:
One - Three - Five - Two - Four in the top ring and then Six - Eight - Ten - Seven - Nine in the bottom ring gets deployed.
IridiumIR @IridiumIR - Satellites have been fueled, pressurized & dispenser tiers are being stacked as we move closer to first launch - Iridium Twitter message
Changing of the Guards
The new bunch of Iridium NEXT satellites will immediately replace the old, almost spent satellites already in service orbits. Being deployed in a lower and thereby faster orbit that slowly intersects the higher orbits of the Iridium Constellation have the advantage that after testing and making sure they can communicate with each other, the ground stations and the old satellites. Then it’s time to change the guards.
The new bunch of Iridium NEXT satellites will change their orbit altitudes, or their shift orbital planes either to the right or left by 30 degree and replace the old satellites one by one all by starting the onboard rocket engine twice first in a transfer orbit and then in a circulation orbit just above the old Iridium satellite, who in turn after handing over its data streams will begin its deorbit burns with whatever little propellant, there must be left in the satellites propellant tanks.
The logical thought you will have is that all 10 Iridium NEXT satellites will raise to their operational altitude as one brand new string of “pearls” in the Iridium Constellation, but that is wrong because there are old dying satellites already in place, and they are all on their last legs some more than others, and they need replacement before they lose their ability to deorbit themselves. A series of Tweets about Iridium makes that clear.
https://twitter.com/iridiumboss/status/824028851353350147
Which reads as follows: - My Ops team is really rocking on shaking out our new Iridium NEXT birds. Just hit 1000 testing activities since launch. Going well! - Follow the Source.
Only three launches deliver all their 10 Iridium NEXT satellites directly into their orbit plane. The five remaining launches all have Iridium NEXT satellites shifting orbit planes.
All of the 75 Iridium NEXT satellites will from their lower test orbit planes overtake the old satellites from below in a tight 10 satellite cluster formation, and when ordered to fire their thrusters one by one thus raising their orbits and their positions.
It’s a complicated relay race in 4 dimensions. Space and Time. Go Einstein.
All operational satellites are flying north in 6 planes 30 degree apart in rows of 11 and then south on the other side of the earth
All satellites are in touch with 4 other satellites and the ground stations whenever one of them fly over one. Then whatever data is available in the network will be sent from satellite to satellite to the ground station and redirected to the individual clients that are using the Iridium NEXT network. For example imagine this scenario.
A cold storage container sends data on position, temperature and current weather to the Iridium satellite passing above it, the data gets relayed through the network to the ground station who informs the client about this and shall we guess a few thousand other cold storage containers on a number of ships worldwide.
Companies need this kind of data if they want to do business with demanding clients.
