news

After the Falcon resumed flight, it ushered in a retaliatory rebound: On August 4, SpaceX once again staged back-to-back launches, with a double launch interval of 7.6 hours: this year's Falcon was the 75th flight, dedicated to launching its own Starlink G11-1; the Falcon was the 76th flight, and for the opponent who was not considered an opponent, the second time a ten-hand rocket was used to launch the Cygnus spacecraft. This was not only the first time that the space express carrier once again carried the Cygnus cargo spacecraft, but also the second time this year after January 30. SpaceX has become the only carrier that has simultaneously covered two types of cargo spacecraft in service in the United States (Cargo Dragon, Cygnus) and three passenger and cargo spacecraft (Crew Dragon, Cargo Dragon, Cygnus), and there is a high probability that it will send a ship to rescue the two astronauts stranded by the Boeing spacecraft in the near future. ‍‍‍‍‍‍‍

The launch was originally scheduled for August 3, but was postponed for one day due to adverse weather conditions. It was finally scheduled for August 4, 2024 at 11:02:53 EST.(23:02:53, August 4, Beijing time), located at Launch Pad 40 at Cape Canaveral Space Force Station in Florida, United States, SpaceX instantly launched its 75th launch of the year, using a ten-stage rocket numbered B1080.10 to carry out a mission code-named NG-21, which is the 21st cargo supply mission for the Cygnus spacecraft to the ISS.

Like the first launch of the Cygnus spacecraft at the end of January this year, this launch also used a ten-hand rocket. It is also the second time that SpaceX has used the rocket with the highest number of reuses to launch passenger and cargo spacecraft. Previously, on March 15, 2023, SpaceX used a seven-hand rocket to launch the cargo Dragon spacecraft; on April 8, 2022 and January 19, 2024, it used a five-hand rocket to launch the manned Dragon spacecraft twice. Of course, in terms of reliability and mission completion, whether it is a ten-hand rocket or a brand new rocket, it is essentially the same.

The rocket used this time is the B1080.10 first-stage rocket. Since its maiden flight in May last year, it has carried out three Dragon spacecraft launch missions, Ax-2, Ax-3, and CRS-30, two commercial launch missions, Euclid and SES-24, and four Starlink missions, Starlink 6-11, 6-24, 6-52, and 6-62. This launch is the fourth time that the rocket has carried passenger/cargo spacecraft to the International Space Station.（Ax-2、Ax-3、CRS-30、NG-21）, like the B1077.10 Ten-hand Rocket, both have been carriedThree passenger and cargo spacecraft(Crew Dragon, Cargo Dragon, Cygnus).

▲ About 7 minutes and 50 seconds after liftoff, this 10-hand first-stage rocket fell from the sky for the 10th time and landed safely at Cape Canaveral Landing Zone 1 (LZ-1). This is the 335th successful rocket recovery by SpaceX, the 261st consecutive successful rocket recovery, the 72nd land recovery of a rocket, and the 42nd time that Cape Canaveral Landing Zone 1 has welcomed a first-stage rocket.

▲Another secondary mission is to recover the fairing. It should be noted that the launch of the Cygnus spacecraft requires the use of the fairing, while the launch of the Dragon spacecraft does not require it because the Dragon spacecraft has its own protective nose cone.

40 minutes after the launch, two reusable fairings worth $6 million splashed down in the Atlantic Ocean about 498 kilometers from the launch site, and were subsequently salvaged and recovered by the GO fleet's multi-purpose ship Bob. This is the 425th and 426th fairing recovered by SpaceX, and the 232nd reusable fairing. Currently, the highest number of uses for a single fairing is up to 20.

About 14 and a half minutes after launch, the second-stage rocket entered the predetermined orbit.(242×251 km, inclination 51.6 degrees)Deploy the Cygnus spacecraft. After orbiting the Earth for a day and a half, at about 3:55 a.m. EST on August 6(Around 15:55, August 6, Beijing time), by American astronaut Matthew Dominic（Matthew Dominick）Operation, using Canadarm2（Canadarm2）The Cygnus spacecraft was captured and docked to the Earth-facing port of the Unity module of the US segment of the International Space Station. This operation is similar to the docking mode of the first-generation cargo Dragon spacecraft to the space station. The second-generation cargo Dragon spacecraft has already been upgraded to autonomous docking mode.

▲By the way, this will be the 50th time that Canadarm2 has captured a spacecraft in space.

According to tradition, Cygnus manufacturer Orbital Sciences Corporation/Northrop Grumman will name each Cygnus spacecraft after a senior NASA astronaut. The 21st Cygnus cargo spacecraft is named SS Francis R. "Dick" Scobee, in honor of Francis Richard Scobee, the commander of the Challenger space shuttle that crashed on January 28, 1986. He participated in the Vietnam War and won the Distinguished Aviator Cross; he served as a U.S. Air Force test pilot and flew dozens of aircraft for thousands of hours; he flew on the Challenger space shuttle twice and finally returned to the sky at the age of 46.

According to the plan, the Cygnus spacecraft will dock at the space station for 5 and a half months, then fly away from the space station in January 2025 with a full load of garbage and eventually burn itself. Another spacecraft that will reenter and burn itself is the second-stage rocket that will undertake this deployment mission.

▲A few hours after the rocket and spacecraft separated, the Falcon second-stage rocket was deorbited in a controlled manner and reentered the atmosphere to burn itself over the South Pacific Ocean east of New Zealand (Nimmo Point, the spacecraft reentry point). The second stage of the Falcon rocket is the only important part that cannot be recovered/reused.

●SpaceX: Preparing to transport stranded astronauts on Boeing spacecraft back

This is the second time SpaceX has carried the Cygnus spacecraft, and it is also the second time that SpaceX has launched a competing cargo spacecraft for a competitor. As a launch company, SpaceX is the only carrier of two types of cargo spacecraft currently in service in the United States (Dragon Cargo and Cygnus), as well as three types of passenger and cargo spacecraft (Crew Dragon, Dragon Cargo, and Cygnus).

There are currently three cargo spacecrafts that supply the International Space Station, two from the United States: the Dragon cargo spacecraft and the Cygnus spacecraft; and one from Russia: the Progress spacecraft. The Japanese HTV White Stork and the European ATV automatic transfer ship have both been retired. The American Dream Chaser cargo space shuttle and the Japanese new cargo ship HTV-X, which are waiting to fly, have slipped from their first flight this year to next year, and the specific first flight time is yet to be determined.

NASA is currently evaluating, or hesitating: whether to use the Crew Dragon spacecraft to rescue the two astronauts who have been stranded on the ISS for two months on the Boeing Starliner, or to take the risk and let the astronauts continue to return on the faulty Starliner?

Several signs show that the possibility of transferring to the Dragon spacecraft is increasing: ① On July 14, NASA suddenly awarded SpaceX a mission fund of 266,678 US dollars as a special research fund for emergency response; ② SpaceX has specially customized cabin spacesuits for the two stranded astronauts (Wilmore and Williams); ③ Internal sources said that Crew-9 is likely to postpone its launch again, and will continue to postpone it from August 18, mainly because of preparations for the transfer spacecraft; ④ NASA has not yet determined when the interstellar spacecraft will return, precisely because Boeing has repeatedly insisted (resisted) on the return of manned interstellar passenger ships; ⑤ The transfer plan has been leaked, Plan 1: The stranded astronauts will return with the four original astronauts on the Crew-8 Endeavour Dragon spacecraft at the earliest; Plan 2: The two stranded astronauts will return on the Crew-8 Endeavour and Crew-9 Liberty respectively, with an interval of 6 months; Plan 3: The stranded astronauts will wait for another 6 months, and return with the four original astronauts on the Crew-9 Liberty at the latest. ‍‍

Regardless of which transfer scheme is ultimately adopted, once it is realized, SpaceX will become the only space carrier to have carried four passenger and cargo spacecraft or their astronauts (Crew Dragon, Cargo Dragon, Cygnus, and Starliner). Boeing Aerospace, which was originally in a state of disrepair, is likely to give up and will not fly Starliner for quite a long time, or even be absent from manned space flight indefinitely. This leaves SpaceX alone to continue to play the role of the savior of the United States in the post-space shuttle era.

▲Cygnus NG-21 mission badge

● Cygnus: The spacecraft with the most rockets

Since its maiden flight on September 18, 2013, the Cygnus spacecraft has carried out a total of 21 cargo supply missions, using three launch vehicles for launch. ① Cygnus spacecraft dedicated rocket - Antares/Antares rocket 17 times(Another failure); ② Atlas V/Atlas V rocket 3 times(4th, 6th and 7th cargo supply missions); ③ Falcon 9 rocket 2 times(The 20th and 21st cargo supply missions have been launched, and the 22nd will be carried out in February 2025)。

If we further break down the Cygnus spacecraft's dedicated rocket Antares, there have been five types of Antares rockets used, namely 110, 120, 130, 230, and 230+. In other words, the Cygnus spacecraft has taken a total of seven types of launch vehicles to complete 21 cargo trips.

In contrast, the SpaceX Dragon cargo spacecraft uses only one rocket: the Falcon 9 B5 rocket; the Russian Progress MS cargo spacecraft uses two rockets: the Soyuz U and the Soyuz 2.1a.

A comparison chart of the Cygnus spacecraft and other cargo spacecraft around the world is shown in the figure below▼

●Why did Cygnus change rockets many times?

It’s a long story, but it can be simply summed up in one sentence: I had no choice but to obey.

At the end of 2011, Orbital Sciences Corporation, the developer of the spacecraft, used Antares, the brightest star in the Scorpius constellation, to create a(Antares/Antares/Antares)The first Antares 110 rocket successfully completed its maiden flight on April 21, 2013. After four successful launches, it encountered misfortune on October 28, 2014. Due to a malfunction of the NK-33 engine left over from the Soviet N1 rocket, the first stage of the rocket suddenly exploded a few seconds after liftoff, resulting in the abort of the third space express of the Cygnus spacecraft.

The next two years were a rectification period. During this period, in order to fulfill the contract signed with NASA to carry cargo supplies to the International Space Station, it had to seek other suitable launch vehicles, so it switched to the ULA Atlas V rocket to continue launching the Cygnus spacecraft.(4th, 6th and 7th ships)。

That crisis led to the demise of Orbital Sciences Corporation(In 2015, it merged with Alliant Techsystems to form Orbital ATK, and in 2018 it was acquired by arms and aerospace giant Northrop Grumman), and forced the company to upgrade. On October 17, 2016, the Antares 230 rocket made its debut and successfully completed its maiden flight. However, this rocket still cannot get rid of the Soviet and Russian supply. Although it abandoned the NK-33 engine developed in the 1970s and replaced it with the relatively new Russian RD-181 engine, it also achieved an impressive record of 13 successful launches in 8 years, but it still could not escape the disaster of supply cut.

The outbreak of war between Russia and Ukraine directly led to a serious shortage of supplies for the new owner of the Antares rocket and Cygnus spacecraft, Northrop Grumman, with only enough inventory for two launches. The 18th Cygnus spacecraft was launched on November 7, 2022, and the last Cygnus was used on August 2, 2023 to deliver the 19th Cygnus. So far, the Antares 230 rocket has turned into a wisp of smoke and dust after it soared into the sky, merging into the sky of history.

The sudden supply cut-off led to the suspension of the Cygnus spacecraft, which is the cruel reality that NASA least wants to see. There are currently three cargo supply lines to the International Space Station. Russia has one: the Progress spacecraft. The United States has two: the cargo Dragon spacecraft and the Cygnus spacecraft. Once the Cygnus spacecraft is out of service, there will only be one line of cargo Dragon spacecraft, which will not only break the risk diversification strategy, but also the number of replenishments will be insufficient. Because the Cygnus spacecraft undertakes two cargo replenishments per year, and the cargo Dragon spacecraft undertakes three replenishments per year. If the number of replenishments is reduced by two-fifths a year, this is unacceptable to NASA and the International Space Station. And it is unrealistic to ask SpaceX to fill the two vacancies of the Cygnus. There are only three cargo Dragon spacecraft in service, C208.4, C209.4, and C211.2. Whether it is launch recovery or refurbishment and reuse, the recycling rhythm is just right. Once the number of launches and replenishments is suddenly increased in a short period of time, it is by no means easy and the risk is also high. In addition, there is no problem with the Cygnus spacecraft itself, but the problem is the shortage of dedicated rockets.

The best emergency plan and the optimal solution is to ensure that the Cygnus spacecraft continues to launch, provided that the launch vehicle is replaced. The first option is of course the Atlas V rocket. After all, this is an old partner that has launched the Cygnus spacecraft three times. But the landlord has no more food. As early as August 2021, ULA announced that the Atlas V entered the countdown to retirement, and the remaining 29 rockets were all booked, leaving no room for the Cygnus launch. As of August 2024, there are only 15 left.

The second option is SpaceX's Falcon 9 rocket. So under the coordination of NASA, three Cygnus spacecraft launch orders were signed in the summer of 2022. The launch schedule is as follows: NG-20 will be launched in November 2023; NG-21 will be launched in January 2024; and NG-22 will be launched in July 2024. But plans are never as fast as changes, and they have been postponed for various reasons. So the launch mission was changed to: NG-20 was launched on January 31, 2024, NG-21 was launched on August 4, 2024; NG-22 is planned to be launched in February 2025.

As for the subsequent missions of NG-23, 24, and 25, who will launch the Cygnus spacecraft in the future?

●What does the new Cygnus mount look like?

As the owner of the Cygnus spacecraft, Northrop Grumman is working with Firefly Aerospace（Firefly Aerospace）The new generation of rocket Antares 330 developed in cooperation(Picture above▲)It will undertake subsequent tasks and will not make its first flight until Q3 of 2025 at the earliest.

In fact, this rocket is not a completely new design, but only partially updated. The first stage of the rocket uses the Miranda engine that is being developed by Firefly Aerospace.（Mirandas）, equipped with 7 units with a design capacity of approximately 735 tons of thrust;The second stage rocket also uses the previousAntares 230+Single Castor solid fuel engine（Castor 30XL）That is to say, apart from replacing the Russian-made engine, other major hardware remains basically unchanged.

It is reported that the new Antares 330 can carry heavier payloads into orbit, with a capacity nearly 30% more than the retired Antares 230 rocket. Northrop Grumman and Firefly Aerospace ultimately hope to upgrade the Antares 330 rocket to an unnamed medium-sized reuse launch vehicle with a more powerful second stage. The maximum capacity for low-Earth orbit is 16 tons, which is twice the 8-ton capacity of the Antares 230 model. And it is hoped that it will be able to compete with the large and medium-sized rockets being developed by Relativity Space and Rocket Lab, and is expected to share more future rockets for military and commercial launch contracts.

However, the Miranda engine was supposed to be tested in the fall of 2023, but it was delayed for a long time. Whether it can be installed on the Antares 330 rocket as scheduled and make its first flight in the third quarter of 2025 is still unknown. In the end, I am afraid that I will have to ask SpaceX for help. Therefore, Northrop Grumman's contract for three Cygnus rockets to be carried by SpaceX Falcon 9 rockets may be just the first contract, and there may be a second contract.

This is not the first time that the arms and aerospace giant Northrop Grumman has tried to make a rocket more powerful than Antares. In 2020, it gave up halfway and abandoned a rocket called Omega.（OmegA）As a launch company, Northrop Grumman is essentially an integrator. It is overly dependent on external suppliers and lacks the mechanism and motivation for technological innovation, which has led to the current predicament.

However, it is precisely because of this that the Cygnus spacecraft has earned a rather ironic nickname - "the Swan that rides the most rockets". It is the cargo spacecraft in the aerospace industry that has replaced the most different types of rockets. It has used or plans to use a total of 8 rocket types: Antares 110, Antares 120, Antares 130, Atlas V, Antares 230, Antares 230+, Falcon 9, and Antares 330.

●Fan-shaped solar wing: beautiful but dangerous

The Cygnus spacecraft is equipped with a pair of fan-shaped solar wings, which are quite iconic. But behind the beauty lies complexity. Is this complex mechanism more prone to failure? The answer is yes. During the 18th cargo supply mission, the unique solar wings failed to unfold normally.

On November 7, 2022, the Cygnus cargo spacecraft carrying out the NG-18 mission successfully entered orbit, but only one solar wing was deployed, and the other could not be deployed. After many attempts, it still could not be deployed. In the end, NASA and the Northrop Grumman team decided to continue the supply mission, giving priority to ensuring that the cargo spacecraft docked with the space station, and temporarily gave up the attempt to deploy the faulty solar wing. In addition, considering that operations such as robotic arm capture and docking of the spacecraft with the space station will generate vibrations, which may trigger the deployment of the solar wing and cause additional risks, an additional risk assessment was conducted on the spacecraft before the robotic arm captured it. After investigation and analysis, it was finally concluded that the most likely reason was that during the separation between the rocket stages, the so-called rocket acoustic cover(acoustic blanket commonly known as sound insulation blanket)The debris happened to get stuck in the solar wing mechanism, preventing it from deploying properly. This is the consequence of over-design, a pit that you dig for yourself.

In stark contrast to this is Musk's five-step work algorithm, one of which is to simplify and remove any unnecessary designs, components or processes. In Musk's original words: "If you don't add back at least 10% later,(Deleted), it means you didn't delete enough at the beginning. "Because of this, the Dragon spacecraft's solar panels all adopt a fixed apron mode, which not only increases the illumination rate but also reduces the failure rate, instead of following the solar wing deployment mode commonly used by other spacecraft.