A new era of spacecraft delivers science on time

When the space shuttle Atlantis stopped during his last mission in 2011, it was truly the end of an era. Few can deny that the program has become too complex and expensive to continue to operate, but even still, humanity’s ability to do useful work in low earth orbit has been seriously affected by the withdrawal of the fleet. of the shuttle. Worse yet, there was no indication when or if another spacecraft would be developed that could truly rival the capabilities of the winged orbiters first designed in the late 1960s.

While its primary function was to carry large payloads such as satellites into orbit, the shuttle’s ability to retrieve objects from space and bring them back was arguably just as important. Throughout his rich career, sensitive experiments conducted at the International Space Station or aboard the Orbiter itself were gently returned to Earth thanks to the craft’s unique design. Unlike traditional spacecraft which ended their flight with a rough dip in the open sea, the shuttle headed for the tarmac like an airplane. Once disembarked, the experiments could be quickly unloaded and transferred to the processing facility at the nearby space station where science teams would wait for further processing or analysis.

For 30 years, the Space Shuttle and its various facilities at the Kennedy Space Center have provided a reliable means of delivering fragile or urgent science experiments to researchers just hours after leaving orbit. It was a valuable service that simply didn’t exist before the shuttle, and that scientists have been deprived of since his retirement.

Until now. With the successful watering of the first Cargo Dragon 2 off the coast of Florida, NASA is on the verge of regaining a critical capacity it hasn’t had in a decade. While it’s still not as convenient as just rolling the shuttle through the orbiter’s processing facility after a mission, the fact that SpaceX can guide its capsule through the waters near the space coast cuts down time dramatically. necessary to return the experiments to the researchers who designed. their.

On the wings of the dragon

Although it took nearly ten years to resume crewed launches from US soil after the Space Shuttle retired, there wasn’t as much downtime for cargo flights. SpaceX put its first Dragon capsule into orbit in 2010, and just over a year after the last flight of Atlantis, they were ready to begin regular missions to resupply the International Space Station. Not only could the privately-developed craft carry 6,000 kilograms (13,000 pounds) of pressurized and unpressurized cargo to the orbiting outpost, it could also bring about 3,000 kg (6,600 pounds) back to Earth.

By comparison, the shuttle could land safely with approximately 14,400 kg (31,700 lb) packed in its cavernous hold. But realistically, this capability was meant to carry satellites and was completely overdone to simply send back racks of science experiments. Price was also a consideration: a Dragon mission cost NASA only a fraction of what a shuttle flight did. Combined with the Dragon’s much higher launch rate, it’s clear which vehicle was best suited for performing regular “milk runs” to the ISS and back.

But there was a downside. Despite SpaceX’s stated intention to make one-time propellant landings with the Dragon one day, the tiny spacecraft ended up splashing into the ocean under parachutes, just like the Apollo and Gemini capsules before it. This meant that returning to Earth on a dragon was a much more difficult race than what the shuttle offered. While this isn’t an issue for many payloads, it could be a wasteful experiment for sensitive experiments such as those designed to study crystal growth in microgravity.

Complicating matters further was the fact that the capsule had descended into the Pacific Ocean, several hundred kilometers offshore. This facilitated recovery operations for the California-based SpaceX, but since NASA did not have appropriate payload processing facilities on the West Coast, the return cargo would have to be transported to the Johnson Space Center in Houston or to the Kennedy Space Center. The prospect of experiments potentially having to undergo a flight across the country before they could be released to scientists has made some research difficult, if not impossible, to do.

The human element

While not ideal, disembarking cargoes and experiments on the west coast and sending them back to Florida was even better than having to bring them back from Kazakhstan if they flew on a Soyuz. But that wouldn’t quite do the trick when the time came for SpaceX to start transporting astronauts as part of the commercial crew program. NASA wanted the main drop-off point of the new Crew Dragon to be as close as possible to the Kennedy Space Center in order to take advantage of existing shuttle-age resources and facilities, with a splashdown in the Gulf of Mexico reserved for unforeseen.

This required a considerable expansion of SpaceX’s recovery capabilities. Two ships, GO Searcher and GO Navigator, were purchased by the company and fitted with medical facilities, a helipad and a rear lifting device to hoist the Crew Dragon floating capsule onto the deck. For redundancy, the two ships are virtually identical and can be deployed simultaneously.

With the transfer of operational resources and trained personnel to the East Coast for Crew Dragon, the recovery of the cargo variant of the spacecraft in California no longer made fiscal sense. In addition, given the similarity of the two vehicles, the experience gained when pulling the Cargo Dragon from the ocean would improve crewed recovery operations. As NASA’s requirements state that astronauts must exit the capsule within 60 minutes of the screening, teams need all the practice they can get.

Beyond the faster delivery time, Cargo Dragon has a number of other advantages over its predecessor. The upgraded capsule has increased payload capacity, twice the number of air-conditioned lockers for storing sensitive materials and a fully autonomous docking system that reduces the workload for astronauts aboard the orbiting outpost . It can also be more easily refurbished for reuse, which not only lowers costs, but allows for a higher launch rate than would be possible otherwise.

In pursuit of the dream

With a helicopter waiting to transport time-sensitive payloads from the recovery ship to the space station’s processing facility, SpaceX can now deliver experiments to scientists between four and nine hours after the splash. This is a huge improvement over what was possible before, and arguably the best one can reasonably expect for an off-shore operation. But it’s still not as fast as the space shuttle.

Ultimately, removing the spacecraft from the ocean and transporting human crew members or science payloads to land by helicopter will always take longer than just landing the vehicle at a designated facility. . Since SpaceX is no longer pursuing targeted propellant landings with its Dragon spacecraft, that means another company will need to step up to meet the challenge of truly rapid payload return.

In this case, this is precisely what the Sierra Nevada Corporation hopes to do with its Dream Chaser space plane. Currently scheduled to fly in 2022 as part of NASA’s Commercial Resupply Services-2 program, the vehicle can return up to 1,750 kg (3,860 lbs) of cargo for a smooth horizontal landing. Being a quarter the size of the Space Shuttle Orbiter, the Dream Chaser has the advantage of being able to use any runway long enough to accommodate a large passenger plane.

This ability to land essentially anywhere on the planet has obvious advantages for international scientific collaboration. But more importantly, when the company completes work on its variant of the human-classified spacecraft, it could be a potentially life-saving capability in the event that a medical emergency requires the transport of a crew member to Earth the most. quickly possible.

Space Force leads the way

The fact that several commercially operated spacecraft are now competing to bring cargo and crew to the International Space Station and beyond is an incredible achievement. This is something that a lot of people in the industry believed would never happen, and things are just getting started. The next decade will see several more vehicles and boosters come online, all striving to be the fastest, most reliable, and of course, cheapest. The democratization of space has officially started.

But as has often been the case in the past, it appears the military is significantly ahead of the curve. The Boeing X-37B spaceplane, now operated by the new Space Force, is an ideal platform for orbital research and development that in many ways is beyond the capabilities of its commercial peers.

Understandably, much is still unknown about the secret craft, but its ability to conduct free flight experiments and return science payloads from space to a soft runway landing has been publicly demonstrated on several occasions. Being fully autonomous, the X-37B is also capable of staying in orbit much longer than any crewed vehicle. This offers a unique opportunity to conduct long-term experiments in complete isolation; something that just isn’t possible on the bustling International Space Station.

As you might expect for an obscure military operation, most of the research carried out aboard the X-37B is classified. Some believe the vehicle is designed to test new reconnaissance equipment and techniques, while others believe it is a testing platform for anti-satellite weapons. But there are signs the Space Force is willing to share its miniature space plane with non-military researchers, with the latest launch in May carrying a record number of NASA experiments.

Ultimately, none of these vehicles can carry more scientific payload than the Space Shuttle, and to date only government-operated craft are able to approach the kind of rapid turnaround needed for truly experiments. urgent. But for the first time in history, there is an array of competitive choices for researchers who wish to place their payload in space and bring it down in one piece; and it is definitely a step in the right direction.