SpaceX has been carefully reviving its launch after 18 days since the last starlink burst, deploying the Fourth Orbital Layer Batch 8 Starlink Mission (StarlinkG4-8) today.
While restarting the high-frequency launch rhythm, a series of extraordinary results were achieved by the way: set a record for the highest reuse of the second one-arrow 11-fly 11 recovery; quickly adjusted the Starlink deployment strategy, switching from 15 minutes of rapid deployment to 1-hour normal deployment mode, the initial orbit exceeded 300 kilometers, as far as possible to reduce the risk of climbing resistance; successful net capture + salvage recovery fairing accumulated to the 100th piece; has now launched 2137 Starlink satellites, currently 1922 in orbit, space operation 1897, The official operation was 1542 and the reload was 215.
● Launch speed glance
● Launch process
▲Starlink Group 4-8 launches the full image
The launch of the fourth orbital layer, the 8th batch of Starlink Group 4-8, can be described as SpaceX's careful recovery of launch vitality. It was originally scheduled to launch on February 20, but it had to be postponed by one day due to the strong winds and waves in the rocket recovery area, coupled with the fact that the offshore recovery platform [lack of solemnity] (ASOG) could not reach the designated area within the established time.
More notably, the deployment was quickly adjusted from a 15-minute rapid deployment to a 1-hour normal deployment mode (deploying the third orbital layer 18, 19, 17, 20, 21, 22, 23, 24, 25, 26, 27, 28 batches), with an initial orbit of more than 100 km over the previous mission, reaching more than 300 km, perigee 325 km x apogee of 337 km. The aim is to send the satellite to a higher orbit and minimize the risk of encountering greater drag in lower orbits by avoiding a magnetic storm for the February 3 deployment mission.
The launch is both the 8th batch of Starlink missions for the fourth orbital layer and the first time that the fourth orbital layer has adopted a 1-hour normal deployment mode.
At 9:44 EST on February 21 (22:44 Beijing time on February 21, a difference of 13 hours), located at launch site 40 of the Space Force Base in Cape Cabo Florida, B1058.11 soared as SpaceX's second one-arrow 11th and flew southeast shortly after takeoff.
1 minute and 12 seconds after liftoff, the Falcon 9 rocket passed through the maximum resistance point of the air (Max Q). At this time, it flies at an altitude of 12 km and a speed of 0.4 km/s. T+2 minutes and 32 seconds, the first stage rocket 9 Merlin engines shut down. Immediately after the separation of the first and second stages, the first stage rocket began to return to the atmosphere fully automatically. At 2 minutes and 43 seconds after liftoff, the second stage rocket ignited for the first time and advanced, and the maneuver turned to fly south to the southeast. The fairing is then released.
▲ After two ignition reversals in the re-entry phase and landing phase, T+8 minutes and 49 seconds, B1058.11 was successfully recovered for the 11th time, and landed vertically on the lack of solemnity (ASOG) maritime platform, at this time about 640 kilometers from the Cape 40 launch site in Cape Florida, northeast of the Bahamas.
This success is determined to be SpaceX's 33rd consecutive successful recovery of rockets, the 107th recovery of first-stage rockets in total, the 81st recovery of rockets at sea, or the 8th recovery of ASOG's "lack of solemnity" rocket.
This live image encountered the caton phenomenon at a critical moment: Why does the Falcon rocket always interrupt the key picture when it lands at sea?
2 seconds before the B1058.11 landed, that is, 8 minutes and 46 seconds after launch, the second stage rocket (the upper stage) turned off the vacuum Merlin engine and began a 48-minute space glide. T+56:38, start the vacuum version of the Merlin engine for the second time, start for 1 second and then shut down again, continue to coast in space.
1 hour, 2 minutes and 55 seconds after launch, the second stage rocket flew at a speed of 7.3 km / s, the star arrows separated, and then deployed 46 1.5 version starlink satellites, the deployment orbit: 325 km perigee x 337 km apogee, equatorial inclination is also 53.22 °. Target orbit: 540 km x equatorial inclination 53.22°.
Just like the previous 12 deployments of the third orbital layer 18, 19, 17, 20, 21, 22, 23, 24, 25, 27, 26, 28) 1.0 starlink, this time at a normal rhythm, it took more than 1 hour from launch to deployment of the satellite. This is also spaceX's 23rd normalized deployment of StarChain.
Each version 1.5 Starlink satellite is only the size of a desk and weighs 290 kilograms, which is slightly heavier than the previous version 1.0 260 kilograms. After unfolding the single-wing solar array, the inexpensive krypton ion thruster gradually climbed, and after being tested and checked by the SpaceX satellite operation and maintenance team, it continued to climb slowly to the final orbit of 540 kilometers, a process that took about several weeks.
●Complete recycling of the 100th piece fairing
About 40 minutes after liftoff, two version 2.5 fairings were controlled and splashed in the northeast waters of the Bahamas, 647 kilometers from the launch site, and were recovered by the BOB Bob multi-purpose ship. This is the 99th and 100th fairing in total that SpaceX has recovered in its entirety. (See figure below for details))
Both four-handed fairings have been used 3 times, and this launch belongs to the 4th use. A new record for the previous use of up to six fairings (launch of the G4-7 Starlink mission on February 3, 2022).
SpaceX has now reused 31 times with at least 60 recyclable fairings, using second-, third-, and fourth-hand fairings multiple times, and up to six-hand fairings.
The first use of a second-hand fairing on November 11, 2019, and the first use of a third-hand fairing on October 6, 2020, from second-hand to third-hand use of fairings, lasted 11 months. In contrast, from the use of second-hand rockets to third-hand rockets, it took 21 months. The road to SpaceX multiplexing is getting faster and faster.
This generation of fairings (version 2.5) is mainly made of carbon fiber aluminum composite materials, costing $6 million, which is less likely to be recycled and reused than recycling rockets. SpaceX once pioneered the fairing recovery system in the world, and when the fairing with auxiliary thrusters and parachutes fell from the sky, it sent a net catcher equipped with a large net and a high-speed driving net in the designated sea area, trying to echo up and down, synchronize in place, and hold the expensive fairing in a net. It's just that there are too many factors that determine whether a successful net capture is too complicated, and the probability of success is low. If the aerial net capture cannot be achieved, it can only be salvaged on the sea surface, which requires the fairing to have super pressure resistance and waterproof ability, especially the seawater immersion is harmless. Overall, most of the reusable fairings are salvaged from the sea.
●What is the performance of the first stage rocket?
This first-stage rocket uses the so-called "eleven-handed rocket", number B1058.11, that is, the 11th use of an arrow, which is the second "eleven-handed rocket" of SpaceX after B1051, which can be described as a well-deserved star-level battle arrow, and the natural record is good.
● StarLink operates 1542 pieces
As of February 21, 2022, Beijing time, SpaceX has launched a total of 2137 Starlink satellites, including the first two Tintin Tintin test satellites, 1 batch of 0.9 satellites (60 satellites), 28 batches of 1.0 satellites (1678 satellites, including 2 batches of polar orbit satellites 13), and 8 batches of 1.5 satellites (397). At present, there are 1922 in orbit, 1897 in space operation, 1542 in official operation, 25 derailed, and 215 in re-entry.
At present, 1542 Satellites are officially operated, accounting for more than 30% of the total number of satellites in orbit in the world. It is definitely a dominant force. The specific launch statistics of Starlink satellites are listed below▼
●Starlink G4-8
The launch, code-named Starlink Group 4-8, represents the fourth orbital layer of the first phase of the first phase of the 8th deployment of the Starlink Constellation. (It should be noted that the Starlink Group 4-2 mission has not been deployed for some reason, so this mission is also the 6th launch of the fourth orbital layer of Starlink)
According to the star-chain constellation design, the fourth orbital layer consists of 72 orbital planes, each of which includes 22 satellites, a total of 1584 satellites, with an operating altitude of 540 km and an equatorial inclination of 53.2°. A total of 397 have been launched (40 have been re-entered).
The first, second, third, and fourth orbital layers, as well as the deployment of the entire constellation▼
○ The second batch of missions to deploy the fourth orbital layer of StarLink (Group 4-2) has not been deployed for some reason.
▲ On February 3, the G4-7 Starlink mission was launched, and then unfortunately encountered G2 magnetic storm interference, resulting in the inability to get out of safe mode, and had to take the initiative to re-enter and burn. This image truly records part of the starlink re-entry ablation scene. Filming time: 2:40 a.m. Atlantic time on February 7 (14:40 Beijing time on the 7th); shooting location: Puerto Rico, Autonomous State of the Caribbean, USA; Filming agency: Caribbean Astronomical Union Puerto Rico Observatory.
○ The eighth batch deploys the fourth orbital layer of the Starlink (Group 4-8): On February 21, 2022, 46 Satellites with an inclination of 53.2° were launched.
● A glance at the Starlink constellations
● SpX launcher refresh data