SpaceX Falcon 9 Block 5 - Starlink L02 - Launching January 7, 2020
Screenshot from SpaceX Starlink L02 January 7, 2020 with host Tim Dodd
Mission Rundown: SpaceX Falcon 9 - Starlink L02
Written: January 5, 2021
Screenshot and copy/paste of mission overview by Geoff Barrett
Still spreading the News 60 times
SpaceX will be launching 60 satellites on top of its workhorse Falcon 9 rocket from the Space Launch Complex (SLC-40) at Cape Canaveral Space Force Station, Florida. This will be the second 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.
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.
B1049 first flew with the Telstar 18V/Apstar-5C satellite on September 10, 2018. After launching Starlink V1.0 L02 the booster’s designation changed to B1049-4.
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. The booster will then land 629 km downrange aboard SpaceX’s autonomous spaceport drone ship ‘Of Course I Still Love You.’ SpaceX will also attempt to recover a fairing half with their fairing catcher vessel: ‘GO Ms. Tree‘. One half was recovered from the water.
The Starlink Payload
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 regarding the constellation's effect on the night sky and earth-based astronomy.
Math: 12000 divided by 60. That's 200 launches. 30000 divided by 60. That’s 500 launches. Are you freaking kidding me? And you need replacements as they fail and deorbit?
That sounds like a steady job to me. Now where do I apply?
Each Starlink V1.0 satellite has a compact design and a mass of 260 kg. SpaceX developed a flat-panel design, allowing them to fit as many satellites as possible into the Falcon 9’s 5.2 meter wide payload fairing. Due to this flat design, SpaceX is able to fit up to 60 Starlink satellites and the payload dispenser into the second stage, while still being able to recover the first stage. This is near the recoverable Falcon 9’s payload capacity to LEO, at around 17 tonnes.
For how small each Starlink satellite is, each one is packed with high-tech communication and cost-saving technology. Each Starlink satellite is equipped with 4 phased array antennas, for high bandwidth and low-latency communication, and two parabolic antennas. The satellites also include a star tracker, which provides the satellite with attitude data, ensuring precision in broadband communication.
Of the initial ~12,000 satellites, ~4,400 would operate on the Ku and Ka bands, with the other ~7,600 operating on the V-Band.
The Starlink satellites are also equipped with an autonomous collision avoidance system, which utilizes the DOD’s debris tracking database to autonomously avoid collisions with other spacecraft and space junk.
Each Starlink satellite is equipped with the first Hall-effect krypton fueled ion thruster instead of xenon. This thruster is used both for ensuring the correct orbital position, but is also used for orbit raising and orbit lowering. At the end of the satellite’s life, this thruster is used to deorbit the satellite.
While the specific impulse (ISP) of krypton is significantly lower than xenon’s, it is far cheaper, which further decreases the satellite’s manufacturing cost, and each satellite only has a single solar panel, which simplifies the manufacturing process.
Such mega-constellations have only recently been made possible with the advent of reusable rocketry, pioneered by SpaceX. For more information on Starlink, I recommend watching the Real Engineering video listed below.
Due to the vast number of Starlink satellites, many astronomers are concerned about their effect on the night sky. However, SpaceX is working with the astronomy community and implementing changes to the satellites to make them harder to see from the ground and less obtrusive to the night sky. SpaceX has changed how the satellites raise their orbits and plans to add a sunshade to reduce light reflectivity.
Now that’s a great question
At 1:01:05 Waldo from South Africa asks: Is South Africa a place to launch rockets from?
That made me look at Google Maps. North of Richards Bay on the South African east coast next to Manzamnyama is a large gravel pit, from where rockets could be launched.
Madagascar is blocking most of the north easterly launch directions, maybe even a launch to the ISS. Maybe if they fly with a “Dogleg” aka. bending the flight during launch, so there is a change of course to orbit. Cape Canaveral is about 28.5o north of Equator as well, and there is a free line of launch to GTO and Polar orbits from the South African launch site.
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