SpaceX Falcon 9 Block 5 - Starlink L09 + Global 7 & 8 - Launched August 7, 2020
Screenshot from SpaceX Webcast of the launch of Starlink L09
Mission Rundown: SpaceX B5 - Starlink L09 + Global 7 & 8
Written: July 21, 2021
Of course We give rides to Backpackers
SpaceX will launch 57 Starlink satellites and 2 BlackSky Global satellites on their Falcon 9 rocket at 01:12 EDT - 05:12 UTC on August 7, 2020, from Launch Complex-39A - LC-39A at Kennedy Space Center, Florida. Starlink L09, is the ninth operational launch of SpaceX’s Starlink communication satellite constellation. This is the 10th flight of Starlink “L0 - L09”.
This will be the 9th operational launch of SpaceX’s near-global satellite constellation – Starlink, which aims to deliver a fast, low-latency broadband internet service to locations where access has previously been unreliable, expensive, or completely unavailable.
After boosting the second stage along with its payload towards orbit, the first stage will perform an entry burn to slow the vehicle down in preparation for atmospheric reentry. Starlink V1.0 L9 first stage booster B1051-5 is set to again land on ‘Of Course I Still Love You‘ 633 km downrange around 8/9 minutes after liftoff.
SpaceX will also attempt to recover both fairing halves with their humorously named fairing catcher vessels: ‘GO Ms. Tree‘ and ‘GO Ms. Chief.’
B1051 first flew the first Crew Dragon for SpaceX’s uncrewed DM-1 mission on March 2, 2019. B1051 launching Starlink V1.0 L09 will change its flight number to B1051-5.
The static fire test for B1051 took place on Wednesday, June 24, when the Falcon 9 rocket with its payload attached was lifted to the vertical position at LC-39A late in the morning. The test was performed that evening at 6:30pm EDT.
SpaceX is the first company to recover and reuse payload fairings. These are new Type 2.2 lifeboat sized fairings - 34 x 17 feet with 8 vents ports, a lowered square protrusion, a heat resistant thermal steel tip and no acoustic tiles inside the fairings.
The Payload
SpaceX plans to offer service in North America by the end of 2020 and estimates that once complete, its venture will make $30-50 billion annually. The funds from which will, in turn, be used to finance its ambitious Mars program.
To achieve initial coverage, SpaceX plans to form a net of 12,000 satellites, which will operate in conjunction with ground stations, akin to a mesh network.
Furthermore, the company recently filed for FCC permission on an additional 30,000 spacecraft, which, if granted, could see the constellation amount to a lucrative 42,000. This would octuple the number of operational satellites in earth orbit, further raising concerns about the constellations' effect on the night sky and earth-based astronomy.
For more information on Starlink, watch the Real Engineering video listed below.
Each Starlink satellite is a compact design that weighs 260 kg. SpaceX developed them to be a flat-panel design to fit as many satellites as possible within the Falcon 9’s 5.2 meter wide payload fairing. 60 satellites fit into a dispenser affixed to the second stage. The entire Starlink payload weighs around 15,600 kg. That’s near the limit that a Falcon 9 can lift into LEO and still have enough propellant for landing.
For such small satellites, each one comes loaded with high-tech communications technology. There are six antennas, four high-powered phased-array and two parabolic ones that all support high-speed data throughput. Starlink also has a built and designed star track navigation system to enable precision placement of broadband throughput.
Four inter-satellite laser links (ISLLs) allow high-speed communication between Starlink satellites. SpaceX placed two ISLLs on the front and rear of the satellite to talk with Starlink satellites in the same orbital plane. They remain fixed in position. Two ISLLs on the satellite’s sides track other Starlink satellites in different orbital planes. This means they have to move to track the other satellites.
The ten launches of one testbed Starlink mission and nine operational Starlink missions V0.9 L0 - V1.0 L09 brings the total number of launched operational Starlink satellites to 535. How many operational Starlink satellites that still work’s, or are in orbit, is no longer up to date. There is only this old article to go by. I don’t count the first 60 Starlink V0.9.
SpaceX will assign 18-20 satellites to three orbital planes. Orbital planes are to satellites as tracks are to trains – they are orbits parallel to each other designed to maximize area coverage while minimizing the number of satellites required.
SpaceX plans to begin offering Starlink service to Canada and the northern United States later this year. Near global coverage is expected to start next year. Pricing has not been made public, but it has been hinted that speeds up to one gigabit may be possible.
BlackSky’s Global 7 & 8 MiniSatellites
BlackSky Global is Spaceflight Industry’s global constellation of Earth-imaging satellites. The constellation provides customers with hourly images with 1 meter of resolution. BlackSky’s goal is to have a constellation of 60 satellites with a sub-1 meter resolution, providing customers with images 4 times per hour.
BlackSky, a division of Spaceflight Industries, is an earth observation company that combines data from multiple sources, including their own satellites, other satellite operators, and social media platforms to provide intelligence to their customers. They are beginning an expansion of their constellation from four to sixteen satellites.
The fifth and sixth satellites in the BlackSky constellation, which each mass 55 kg, are the first satellites manufactured by LeoStella, a joint venture of Spaceflight Industries and Thales Alenia Space. Four more BlackSky satellites are scheduled to launch on an Indian SSLV rocket later this year, and the company hopes to launch another six on various missions through early 2021.
Only two BlackSky satellites have been sent to Sun Synchronous Orbit SSO orbits that give a view of the entire globe. The rest of the sixteen satellites are going to mid-inclination orbits that will allow more frequent observations of highly populated areas.
The rideshare arrangements were managed by Spaceflight Inc., a former corporate sibling of BlackSky under their Spaceflight Industries parent. The rideshare business was recently split off and sold to new owners Mitsui & Co., Ltd., in partnership with Yamasa Co., Ltd, of Japan. Spaceflight Industries will now focus on their BlackSky division.
This mission is called SXRS-1 by Spaceflight Inc., with the SXRS-3 rideshare occuring around the end of the year, and presumably an SXRS-2 rideshare also planned. SXRS-3 will be carried on SpaceX’s SSO-1 dedicated rideshare mission, with Spaceflight carrying a combination of microsatellites, cubesats, and hosted payloads for different customers on a non-propulsive free flying dispenser, similar to what they did on the earlier SSO-A flight.
This is the second of what is expected to be three consecutive rideshares on Starlink flights. Planet launched three of their SkySats on the previous Starlink mission, and has three more manifested on the next mission that is expected to launch NET late July.
The Starlink missions fill a niche in the rideshare market by providing frequent flights to mid-inclination orbits for passengers that can perform their own orbit raising from the low Starlink deployment orbits.
While recent Starlink missions have deployed to an altitude of approximately 200 x 380 km, pre-mission launch data on CelesTrak shows this mission is targeting a higher deployment orbit around 388 x 401 km. The increase in altitude might make it easier for the BlackSky satellites to reach their operational orbits.
SpaceX has also booked a great many customers for upcoming dedicated rideshare flights to Sun Synchronous Orbit, which will deploy at higher altitudes.
Ion Drive with Krypton gas
Innovative ion propulsion technology keeps these satellites in the correct position while on orbit. They use ion Hall-effect thrusters to achieve their working orbit. Each Starlink satellite incorporates an autonomous collision avoidance system. It uses the Department of Defence’s debris tracking data to avoid colliding with space debris or other satellites.
Starlink’s low altitude also allows SpaceX to easily deorbit malfunctioning satellites, even if their engines fail. Although 100 km is commonly described as the upper limit of Earth’s atmosphere, there is no “hard barrier”. Even at 550 km altitude, there is still a slight amount of atmospheric drag pulling the satellites down. Each satellite’s onboard ion Hall-effect thruster engines is powerful enough to keep it in orbit, but if the engine fails, it will fall back to Earth within about a year.
The minuscule atmospheric drag in low Earth orbit will help ensure that dead satellites don’t stay in orbit for long. This will help reduce the amount of space debris in orbit, which is rapidly becoming a major concern.
Starlink Satellite Constellation
SpaceX plans eventually to form a network of about 12,000 satellites. They will operate roughly 4,400 satellites using Ku- and Ka-band radio spectrum, and almost another 7,500 satellites in the V-band.
To achieve initial coverage, Starlink will use 72 orbital planes, angled at 53 degrees from the Earth’s equator at an altitude of 550 km. They will put 18-22 satellites into each of these orbital planes, totalling 1,584 satellites. They will communicate with other Starlink satellites and with ground stations, akin to a mesh network.
In late 2019, the company asked the American Federal Communications Commission (FCC) for permission to launch an additional 30,000 satellites into orbits ranging from 328 km to 580 km in altitude. If the FCC okays the request, the constellation could grow to 42,000 satellites. This would increase the number of operational satellites in Earth orbit by at least a factor of 20 from pre-2019 levels.
The constellation’s large numbers are raising concerns regarding their effect on the night sky and Earth-based astronomy. However, Elon Musk stated that he is confident that SpaceX can mitigate light pollution issues and is working with industry experts to minimize the potential for any impact. Future Starlink satellites will use a sunshade that is a patio-like umbrella to reduce light reflectivity.
This batch of 57 Starlink satellites should be "VisorSat" fitted with the new sunshade to help reduce the brightness of the satellites as seen from the ground. These visors will deploy shortly after spacecraft separation during Saturday’s launch.
As was the case with a single Starlink satellite on the V1.0 L07 mission (launched on June 4), all Starlink satellites that will launch on subsequent missions going forward will feature a sun shade or visor, which will assist in blocking sunlight from reflecting off the majority of the spacecraft body while in orbit and reducing its overall albedo/intrinsic brightness as observed from the ground.
Starlink ground antennas
Prototypes of the Starlink user terminal antenna have been spotted alongside the other antennas at Starlink gateway locations in Boca Chica, Texas and Merrillan, Wisconsin. These user terminals will be crucial to the success of the Starlink network.
SpaceX board member Steve Jurvetson recently tweeted that the company’s board had an opportunity to try out the user terminals at the company headquarters in Hawthorne. The devices use a Power over Ethernet (PoE) cable for their power and data connection. The antenna connects to a SpaceX branded router with Wi-Fi (802.a/b/g/n/ac, transmitting at 2.4 & 5GHz). SpaceX is producing the antenna assemblies in-house while outsourcing production of the more common router component.
SpaceX continues to make progress setting up its network of 34 gateways for the Starlink system. New gateways are being added in the Northwest and North Central U.S. with locations in Northern California, Idaho, Minnesota, Montana, Washington, and Wyoming. In the Southeastern U.S. Previously filed gateways in Tennessee and Florida were removed while new gateway locations were added in Arizona, Georgia Kansas and Alabama.
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