How will NASA and SpaceX destroy the International Space Station?

On July 17, NASA and SpaceX outlined plans to burn up the space station and dump what remains in the ocean, ideally in early 2031 when the station reaches its 32nd year. The space agency has rejected other options, including dismantling the station and taking everything home or handing over the keys.

Earlier in June, NASA awarded SpaceX an $843 million contract to land the International Space Station, the largest structure ever built off the planet.

The International Space Station flies at an altitude of more than 400 km above the Nile Delta in Egypt. Photo: NASA

Why destroy the space station?

The International Space Station is showing signs of aging. Russia and the United States launched the first components of the station in late 1998, and astronauts moved in two years later. Europe and Japan contributed their own parts to the station, while Canada provided the robotic arm.

The ISS has grown to the size of a football field, with a mass of about 430,000 kg. NASA estimates that the station will last until at least 2030. At that time, it hopes that private companies will be able to launch their own space stations into space, with NASA as one of many customers.

This strategy would allow NASA to focus its time and resources on tourism to the Moon and Mars. NASA could also decide to extend the station’s lifespan, if no commercial outposts are already there, to allow for uninterrupted scientific research.

Why not bring the space station back to Earth?

NASA has considered dismantling the space station and towing it piece by piece back to Earth, or letting private companies salvage individual components for their own planned projects.

But according to NASA, the space station is not designed for the idea of ​​disassembling in orbit, and any such attempt would be expensive and risky for the astronauts handling the disassembly. Besides, there is no spacecraft as large as NASA's space shuttle, which was retired in 2011, to bring everything down. Another option was to put the space station in a higher, more stable orbit, but that was also ruled out due to logistical problems and the increased risk of space debris.

How to put a space station into orbit?

To maintain its orbit at an altitude of about 420 km, the space station needs to be boosted by periodically visiting spacecraft. If these spacecraft were to stop being deployed, the space station would continue to descend until it became uncontrolled and fell out of orbit.

NASA wants to ensure the space station re-enters safely over a remote area of ​​the South Pacific or possibly the Indian Ocean, meaning NASA will launch a spacecraft that will dock with the station and steer the station toward a landing site in the ocean.

NASA hopes to collect some of the station’s debris, ranging in size from a microwave to a car, in a landing strip up to 2,000 kilometers long. NASA and its partners considered using three Russian craft for the job, but needed a more powerful spacecraft. By June, SpaceX had won the contract for the mission.

What will a spacecraft leaving orbit look like?

SpaceX plans to use the Dragon spacecraft, which carries supplies and astronauts to the space station but has a larger compartment, holding a record 46 engines and more than 16,000 kg of fuel.

The challenge will be to create a spacecraft strong enough to navigate the space station while counteracting the increased drag and atmospheric drag that will occur during the final landing, SpaceX’s Sarah Walker said. According to NASA, the spacecraft will need an exceptionally powerful rocket just to get to orbit.

The capsule will launch a year and a half before the station is scheduled to be decommissioned. The crew will return home six months before the station is destroyed. Once the station has dropped to an altitude of about 220 kilometers, Dragon will bring the station down four days later.

NASA wants to bring back some small items from the space station to display in the museum, like the spacecraft's bell and logs and other mementos. Those could be dropped off on a SpaceX supply ship in the last year or two.

Ngoc Anh (according to AP)

Source: https://www.congluan.vn/nasa-va-spacex-se-pha-huy-tram-vu-tru-quoc-te-nhu-the-nao-post303935.html