European decision hits NASA’s space launch system (SLS) devastating

Nowadays, NASA’s decision to launch one of their future missions on a commercial rocket is hardly a surprise. After all, the agency is now willing to let their astronauts fly on boosters and spacecraft built and operated by SpaceX. Increasing competition has made space cheaper and easier than ever before, so it only makes sense that NASA would reap the rewards of a market they helped create.

So the recent announcement that NASAs Europa Clipper mission will officially fly on a commercial launch vehicle, perhaps looking more of the same. But it’s not just a mission. It is a flagship interplanetary probe designed to study Jupiter’s lunar Europe in unprecedented detail and serve as a signpost for a future mission that will hit the icy surface of the moon. Due to the extreme distance from Earth and the intense radiation from the Jovian system, it is considered one of the most ambitious missions NASA has ever attempted.

With no margin of error and a total cost of more than $ 4 billion, the fact that NASA trusts a commercial booster to carry this extraordinarily valuable payload is in itself important. But perhaps more importantly, until now, Europa Clipper was ordered by Congress to fly on NASA’s Space Launch System (SLS). This was at least in part due to the incredible power of the SLS, which Knipper on the fastest route in the direction of Jupiter. But more pragmatically, it was also seen as a way to ensure that work on Shuttle’s super-heavy-duty rocket would continue fast enough to be ready for the mission’s launch window in 2024.

But as the deadline quickly approached, and engineers felt the pressure to ignite the spacecraft last before attaching it to the launch vehicle, NASA appealed to Congress over the flexibility to fly Europa Clipper on a commercial rocket. The agency’s official line is that they can not spare an SLS launch for the European mission while supporting the Artemis Moon program at the same time, but through the Knipper to fly on another rocket in the Consolidated Appropriations Act of 2021, Congress effectively removed one of the only justifications still available for the disturbing space launch system.

To Europe, finally

There is no doubt that the SLS, at least on paper, would have been the ideal vehicle to Europa Clipper on his epic journey. The megarocket would have enough energy to send the probe of about 6 065 kg (13 371 lb) on a direct orbit to Jupiter during its closest pass in 2024, which will take the planet within 611 million kilometers (380 million miles) of the earth sou bring. On this flight it will take a little less than three years for the Knipper to orbit Jupiter and begin its scientific mission.

Europe as seen by the Galileo spacecraft.

Unfortunately, there is simply no replacement for the SLS in terms of raw power. While future vehicles from SpaceX, Blue Origin and United Launch Alliance may be compelling options, they simply will not be ready in time for the 2024 launch window. Even if they are operational by that time, and that is by no means a guarantee, they will certainly not have enough flights to prove their reliability. NASA could conceivably wait until one of the later launch windows in 2025 or 2026 to give commercial operators more time to bring their next-generation heavy-lift vehicles online, but at least that’s not in the cards.

So how do you get to Europe without the huge boost that the SLS offers? In a word, slowly. Although there were earlier speculations that the spacecraft could provide a small ‘kick-stage’ to compensate for the reduced initial velocity, the preliminary launch contract information by NASA specifies that the spacecraft will use gravity auxiliary maneuvers by flying what is known as a Mars-Earth-Gravity-Assist (MEGA) job. This will be the Europa Clipper to reach its destination without any hardware adjustments, but the downside of this complex track dance is that the journey will take more than twice as long to complete, and the probe will only reach Europe in early 2030.

It has not yet been determined which rocket will eventually launch the rocket. Knipper, and the decision will probably only come next year after the formal selection process has been completed. Since the SpaceX Falcon Heavy has the highest payload capacity of any current rocket in the world, it is the most likely choice. Even still, it will potentially have to be launched in the still unused fully usable mode.

So long, Shelby

This first public acknowledgment that NASA no longer intends to fly Europa Clipper on the Space Launch System comes days after Richard Shelby, senator from Alabama, one of the strongest supporters of the SLS program, announced that he would retire next year. Concerned that the cancellation of President Obama’s Constellation program in 2010 at the Marshall Space Flight Center in Huntsville, Alabama, would no longer mean the center of the US space agency, Senator Shelby fought hard to ensure SLS a flagship program would be to compete the Saturn V. and spacecraft:

Without the development of heavy-lifting rockets, people will not be able to explore space beyond what they can do with the Shuttle today.  NASA's ability to achieve our goals for future space exploration has always been through Marshall Space Flight Center.

Although few would complain about politicians actively interested in space exploration, and retaining hundreds of well-paid aviation jobs in his district, it was a commendable achievement, costing Shelby’s support to NASA a prize. He vehemently opposed NASA’s partnerships with commercial launch providers, and went so far as to call the agency’s early contracts with companies such as SpaceX a ‘faith-based initiative’ and a ‘commercial space welfare program’ as the new airlines. . had yet to demonstrate that they can build a booster capable of reaching a trajectory.

It’s a safe bet that replacing Senator Shelby will follow a similarly positive approach to Marshall Space Flight Center, but it’s hard to imagine them taking the leaps made by commercial launch providers in recent years, can ignore. As the private industry is rapidly replicating through the latest engine and booster technology, the reliance on the Space Launch System on Shuttle-derived hardware invented in the 1970s is only becoming harder to defend.

Difficult decisions in advance

Amid the embarrassment of the “Green Run” failure in January, the loss of the Europa Clipper mission and the resignation of Senator Shelby, the future of the space launch system has never been more uncertain. If you add a White House that is much more concerned about fighting a deadly pandemic than leaving new bootprints on Mars or the Moon, it’s not hard to see how the often delayed and incredibly expensive program will eventually run out.

To be sure, the SLS will fly at least once. NASA and Boeing are preparing to repeat the failed engine test in the next few weeks, and too much time and money has been invested not to proceed with the Artemis I mission. Even if NASA finally decides to end the SLS program in favor of further commercial cooperation, the shutdown flight is just as much a test for the Orion crew vehicle. With a number of more Orion capsules already under construction for future Artemis missions, the development of the Apollo-like capsule will almost certainly continue with or without the SLS.

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