Starlink 16 | Falcon 9 Block 5

Lift Off Time	January 20, 2021 – 13:02:34 UTC | 08:02:34 EST
Mission Name	Starlink V1.0 L16; the 17th Starlink mission
Launch Provider (What rocket company launched it?)	SpaceX
Customer (Who paid for this?)	SpaceX
Rocket	Falcon 9 Block 5 B1051-8; 38 day turn around
Launch Location	Launch Complex 39A (LC-39A), Kennedy Space Center, Florida, USA
Payload mass	15,600 kg (~34,000 lbs) (60 x 260 kg, plus dispenser)
Where did the satellites go?	550 km circular Low-Earth Orbit (LEO) (Initially 366 x 213 km)
Did they attempt to recover the first stage?	Yes
Where did the first stage land?	B1051-8 successfully landed 633 km downrange on Just Read the Instructions Tug: Hawk; Support: GO Quest
Did they attempt to recover the fairings?	Yes, outcome both fairing halves were destroyed and not recovered due to rough seas
Were the fairings new?	No, one fairing flew on Starlink V1.0 L3 and L10, and the other one flew on Starlink V1.0 L9; 155 and 167 days turn around, respectively
This was the:	– Fastest turn around time of a booster ever at 38 days (Previous Record: 51 days) – Strongest wind that a Falcon 9 booster successfully landed on an ASDS in – 1st 8th flight of a booster – 7th Falcon 9 launch without a static fire (despite being the fleet-leader) – 105th Falcon 9 launch – 51st re-flight of a booster – 2nd re-flight of a booster in 2021 – 72nd booster landing – 22nd consecutive landing (New record for SpaceX) – 18th landing attempt on JRTI – 17th and 18th re-flight of a fairing half – 2nd launch for SpaceX in 2021 – 1st SpaceX launch on January 20 – 30th SpaceX launch from LC-39A – 1,013th Starlink satellite launched – 5th orbital launch of 2021
Where to watch	Official replay Everyday Astronaut replay

How did it go?

SpaceX successfully launched their Starlink V1.0 L16 mission from Launch Complex 39A (LC-39A), at Kennedy Space Center, in Florida. The Falcon 9 had 60 Starlink satellites on board. Starlink 16 marked the 16th operational Starlink mission, boosting the total number of Starlink satellites launched to 1,013.

This launch also set a number of reuse milestones. Most notably, this launched marked the first time a booster flew and landed a total of 8 times. Making this even more impressive, the booster flew just 38 days ago on the SXM-7 mission. The booster landing was an “envelope expansion,” meaning it landed in the highest winds ever recorded for a droneship landing.

What is Starlink?

Starlink is SpaceX’s internet communication satellite constellation. The Low-Earth orbit constellation will deliver fast, low-latency internet service to locations where ground-based internet is unreliable, unavailable, or expensive. 

Starlink is currently in limited public beta, but a wider release beta is expected to start in under 3 months. As of now, only higher latitudes are covered (between 44 and 52 degrees according to one source). However, SpaceX only needs 24 launches for global coverage. Given SpaceX’s current Starlink production and launch rate, Starlink will have global coverage by the middle of 2021.

Once Starlink is complete, the venture is expected to profit $30-50 billion annually. This profit will largely finance SpaceX’s ambitious Starship program, as well as Mars Base Alpha.

What is the Starlink Satellite?

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. 

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. 

To decrease costs, each satellite only has a single solar panel, which simplifies the manufacturing process. To further cut costs, Starlink’s propulsion system, an ion thruster, uses Krypton as fuel, instead of Xenon. 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.

Ion Power

Each Starlink satellite is equipped with the first Hall-effect Krypton powered ion thruster. 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.

What is the Starlink Satellite Constellation?

A satellite constellation is a group of satellites that work in conjunction for a common purpose. Currently, SpaceX plans to form a network of roughly 12,000 satellites; however, in 2019 SpaceX filed an application with the Federal Communication Commission (FCC) for permission to launch and operate an additional 30,000 satellites. These additional satellites would be placed in orbits ranging from 328 km to 580 km, which would further decrease latency, and increase the bandwidth. To put this number of satellites into perspective, this is roughly 20 times more satellites than were launched before 2019. 

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. 

To achieve initial coverage, SpaceX will use 72 orbital planes, in a 53 degree 550 km circular orbit. The Starlink satellites will then communicate with other Starlink satellites and ground stations, to form a mesh network. 

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, starting on Starlink V1.0 L9, added a sunshade to reduce light reflectivity. These changes have already significantly decreased the effect of Starlink on the night sky.

What is Falcon 9 Block 5?

The Falcon 9 Block 5 is SpaceX’s partially reusable two-stage medium-lift launch vehicle. Block 5 is the final iteration of the Falcon 9; the goal is to apply all the lessons learned from 56 previous Falcon 9 pre-Block 5 flights into a human-rated reusable rocket. The Falcon 9 contains 3 main components: a reusable first stage, an expendable second stage, and a reusable fairing.

Block 5 updates:

SpaceX introduced a lot of changes on Block 5, allowing it to become the crew-launching reusable rocket that we know today. To start, the Composite Overwrapped Pressure Vessels (COPVs) had to undergo a complete redesign. NASA mandated the COPV redesign, as it had been the cause of both of the Falcon 9 failures: AMOS-6 and CRS-7.

Alongside with certification for human spaceflight, Block 5 came with a number of other major changes. To increase the amount of flight each booster could handle, and decrease the turnaround time, SpaceX reinforced the landing legs, upgraded the grid fins, and added a carbon fiber interstage. They also added heat-resistant external paint and upgraded the engines. For more information about the changes in Block 5, and the other Blocks of the Falcon 9, check out this video by the Everyday Astronaut:

Falcon 9 Booster B1051

The booster that supported this mission was B1051. This booster is the current fleet leader with 7 previous flights. Its maiden flight was launching the first Crew Dragon for SpaceX’s uncrewed Demo-1 mission in March 2, 2019. The booster’s second flight was launching the RADARSAT constellation from Vandenburg, on June 12, 2019. B1051 then launched the Starlink V1.0 L3, L6, L9, and L13. The booster’s seventh flight was on the SXM-7 mission, which launched on December 13, 2020. This marks the shortest turnaround time of a booster to date at just under 40 days. This is a significant decrease from the current turn around time record, which is 51 days. Starlink V1.0 L16 will change the booster’s designation to B1051-8.

Following stage separation, the Falcon 9 will conducted 2 burns. These burns softly touched down the booster on Just Read the Instructions

Fairing Reuse

SpaceX is the first entity ever that recovers and reflies its fairings. The recovery vessels, Go Ms. Tree and Go Ms. Chief, will most likely attempt to recover the fairing halves. After being jettisoned, the two fairing halves will use cold gas thrusters to orientate themselves as they descend through the atmosphere. Once at a lower altitude, they will deploy parafoils to help them glide down to a soft landing for recovery. 

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Starlink 16 Full Mission Profile

Hr/Min/Sec              Event

– 00:38:00                 SpaceX Launch Director verifies go for propellant load.
– 00:35:00                 RP-1 (rocket grade kerosene) loading underway.
– 00:35:00                 1st stage LOX (liquid oxygen) loading underway
– 00:16:00                 2nd stage LOX loading underway
– 00:07:00                 Falcon 9 begins engine chill prior to launch
– 00:01:00                 Command flight computer to begin final prelaunch checks
– 00:01:00                 Propellant tank pressurization to flight pressure begins
– 00:00:45                 SpaceX Launch Director verifies go for launch
– 00:00:03                 Engine controller commands engine ignition sequence to start
– 00:00:00                 Falcon 9 Liftoff

Launch, Landing, and Satellite Deployment*

Hr/Min/Sec              Event

00:01:12                   Max Q (moment of peak mechanical stress on the rocket)
00:02:32                   1st stage main engine cutoff (MECO)
00:02:36                   1st and 2nd stages separate
00:02:44                   2nd stage engine starts (SES-1)
00:03:10                   Fairing deployment
00:06:40                   1st stage entry burn complete
00:08:26                   1st stage landing
00:08:46                   2nd stage engine cutoff (SECO-1)
00:45:35                   2nd stage engine starts (SES-2)
00:45:36                   2nd stage engine cutoff (SECO-2)
01:04:32                   Starlink 16 payload deploy

* All times are approximate