Russia has even suggested it may pull out of the ISS as early as 2025. "Nasa is hedging its bets on Russian participation," says Wendy Whitman Cobb, a space policy expert from the US Air Force's School of Advanced Air and Space Studies. Recent problems with some Progress vehicles, however, and the worsening political situation with Russia, has led to Nasa investigating its space tug alternative. Here, Russian Progress spacecraft are earmarked to then give the station a final push back into the planet's atmosphere. Once the final crew has left, the station's altitude will drop further to 280km (175 miles), deemed the point of no return – where the station could no longer be boosted back above the drag caused by our planet's thickening atmosphere – a process that will take several months. "That is still in discussion," says Aschbacher. At this point a final crew will be sent to the station, likely ensuring any remaining equipment or items of historical significance that have yet to be removed are done so, also reducing the weight of the station. Instead, the plan outlined by Nasa in a report last year is to push the entire station back into the atmosphere.Įvents will begin in 2026, when the orbit of the ISS will be allowed to naturally decay under atmospheric drag, dropping from 400km (250 miles) to about 320km (200 miles) in mid-2030. Other alternatives, such as boosting it to a higher orbit, are inconceivable, according to Nasa, as they would require dozens of boosting spacecraft to push the station to a safe altitude. The lifetime of the ISS has been extended several times, but it's widely agreed that extending it beyond 2030 would be risky. A rotating crew of seven inhabit the station today. "It's like the pyramids of Giza," says Laura Forczyk, a space analyst at the US consulting firm Astralytical. At 109m (356ft) in length it is the size of a football field, the largest human structure ever assembled in space. "A 400-tonne object falling out of the sky is not great."īeginning as the single Russian-built Zarya module in 1998, the station today is enormous, boasting 16 modules, vast solar panels mounted on a metallic truss, and radiators to expel heat. "It is a significant challenge," says Jonathan McDowell, an astronomer at the Harvard–Smithsonian Center for Astrophysics in the US. The ISS represents a whole new problem, however, being more than three times the size of Mir. Many large objects have burned up in the Earth's atmosphere, most notably Russia's Mir space station in 2001 and Nasa's Skylab space station in 1979. Working out how exactly to deorbit the station is a mammoth undertaking. Kathy Leuders, head of Nasa's human spaceflight programme, later revealed it was estimated the tug vehicle would cost just shy of $1bn (£800m). This will be the largest re-entry in history and, in March, Nasa asked Congress for funding to start development of a "space tug" that might be needed to perform the task – a spacecraft that can push the station back into the atmosphere. To prevent such a catastrophe in space from happening once more, the space station will be deorbited in 2031, bringing it through the atmosphere to safely splash down in the Pacific Ocean. "We really don’t want to go through that again," says Cathy Lewis, a space historian from the National Air and Space Museum in the US. "It is really one of the big international victories," says Thomas Zurbuchen, Nasa's former head of science.īut much of its hardware is decades old, which could eventually see the station become dangerous or even uncontrollable in orbit – a fate that befell the Soviet Union's Salyut 7 space station in 1985, requiring two cosmonauts to revive the tumbling station. It has been a boon for international collaboration, not least between the US and Russia, who partnered shortly after the fall of the Soviet Union. "The space station has been a huge success," says Josef Aschbacher, the head of the European Space Agency (Esa), one of the more than a dozen partners in the programme. It has hosted more than 250 visitors from 20 countries since its first crew arrived in November 2000.
The ISS has been orbiting the Earth since construction on it began in 1998. This raging inferno will crash into the ocean, across an area maybe thousands of kilometres in length, signalling the end of one of humanity's greatest projects – the International Space Station (ISS). Tearing through the sky will be some 400 tonnes (880,000lbs) of metal, set aglow by its re-entry through the atmosphere. Drift into the wrong part of the Pacific Ocean in eight years, and you might be in for a shock.
0 kommentar(er)
