A flying turkey
The Space Launch System is yesterday’s rocket, powered by yesterday’s technology and brought about by yesterday’s thinking
ONDECEMBER 14th 1972 Eugene Cernan, commander of Apollo 17, took a last look around the Taurus-Littrow valley, climbed his lunar module’s ladder and blasted off for home. His were the final footprints so far pressed into the Moon’s surface. Indeed, no human being since then has ventured more than a few hundred kilometres from Earth.
Nor will that change on August 29th, the current scheduled lift off, from the Kennedy Space Centre in Florida, of the first flight of NASA’s Space Launch System (SLS), heir to the mighty Saturn Vs that carried the Apollo project to the Moon, and putative workhorse of the Artemis programme, Apollo’s tardy follow-up, which has its eyes first on the Moon and then on Mars. Instead, the SLS will send a capsule called Orion, carrying three mannequins wired with radiation sensors, to the Moon’s vicinity. This will arrive, if all goes well, on September 3rd. And if it continues to go well, people (four of them) will follow the dummies into lunar orbit in 2024, and a further two will make new footprints, perhaps at the Moon’s south pole, in 2025.
Back to the future
It all sounds terribly futuristic. It isn’t. Artemis, named after Apollo’s twin sister, who was goddess of the Moon as he was god of the Sun, is a mishmash, built on top of previous, abandoned plans to return to the Moon. And the SLS, in particular, looks like an attempt to relive the 1960s using the technology of the 1970s. It is not merely an homageto the Saturn V (though not quite as powerful). Much of it is built from re-used and repurposed components from the Space Shuttle, an experimental spaceplane that first flew in 1981, just eight years after the last Saturn V went up.
The SLS’s distinctive orange body, for instance, is a stretched version of the Shuttle’s external fuel tank. Attached to the bottom are four of the same RS-25 engines that powered the Shuttle itself (each of the engines on the rocket currently on the launch pad has been into space several times before). Strapped either side are a pair of solid-rocket boosters, likewise stretched, that are also derived from those that helped the Shuttle into orbit.
Building on old technology was not NASA’s idea. The SLS was created by Congress, and foisted on an unwilling Barack Obama in an effort to protect manufacturing jobs, particularly in Alabama, where much of the Shuttle was built. Critics have dubbed it the “Senate Launch System”.
Despite being made from recycled material, which was supposed to save money, the SLS is both late and expensive. It was originally scheduled to take off in 2016. Its development cost is $23bn and climbing. The cost per launch depends on how many launches eventually happen, but one official estimate puts it at more than $2bn.
原文出自：2022年8月27日《The Economist》Science & technology版塊，僅供個人英語學習交流使用。
本文由 @多源焦點 修订发布于 2022-09-09 06:28:56