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Inside the Mission To Europa (arstechnica.com)
An anonymous reader writes: Ars Technica details the political and engineering battles being waged to make it possible for NASA to land a probe on Jupiter's moon Europa. They have new information about mission plans; it sounds ambitious, to say the least. "First, the bad news. Adding a lander to the Clipper will require additional technical work and necessitate a launch delay until late 2023. At that time, the massive Space Launch System rocket NASA is developing could deliver it to Jupiter in 4.6 years. Once there, the lander would separate from the Clipper, parking in a low-radiation orbit.
The Clipper would then proceed to reconnoiter Europa, diving into the harsh radiation environment to observe the moon and then zipping back out into cleaner space to relay its data back to Earth. Over a three-year period, the Clipper would image 95 percent of the world at about 50 meters per pixel and three percent at a very high resolution of 0.5 meters per pixel. With this data, scientists could find a suitable landing site. ...The JPL engineers have concluded the best way to deliver the lander to Europa's jagged surface is by way of a sky crane mechanism, like the one successfully used in the last stage of Curiosity's descent to the surface of Mars. With four steerable engines and an autonomous system to avoid hazards, the lander would be lowered to the moon's surface by an umbilical cord."
The Clipper would then proceed to reconnoiter Europa, diving into the harsh radiation environment to observe the moon and then zipping back out into cleaner space to relay its data back to Earth. Over a three-year period, the Clipper would image 95 percent of the world at about 50 meters per pixel and three percent at a very high resolution of 0.5 meters per pixel. With this data, scientists could find a suitable landing site. ...The JPL engineers have concluded the best way to deliver the lander to Europa's jagged surface is by way of a sky crane mechanism, like the one successfully used in the last stage of Curiosity's descent to the surface of Mars. With four steerable engines and an autonomous system to avoid hazards, the lander would be lowered to the moon's surface by an umbilical cord."
Constellation killed itself, massive cost overruns were pushing it into the $150 - 230 Billion dollar range. SLS is bad, but nowhere near that bad coming in at the $40 - $80 Billion price range.
SpaceX's Dragon has already launched to orbit 8 times, including 6 full resupply missions to ISS, autonomously. It rides the Falcon-9, which has successfully reached orbit 18 times.
The manned Dragon capsule configuration (aka Dragon 2) is expected to do a demo flight in about a year. It was delayed by the accident investigation due to one faulty support spar (of which thousands had already flown) in May of this year. Falcon 9 is scheduled to return to flight in about a month, but it has a backlog of missions/payload before it can fly the Dragon 2 Demo flight, currently expected in the second half of 2016.
Yeah, we temporarily stumbled on manned space flight -- but we've done so before (e.g. after the two Shuttle disasters). It's not permanent.
If you can go to bed, knowing you did a valuable thing today, you're very lucky. If you can't... it's not bedtime
My way too many hours of Kerbal Space Program make me highly qualified (joke) to say that bringing something back is way harder than just putting stuff there. If you make a later stage twice as big, you need to make every stage leading up to it twice as big as well. Getting samples back up to orbit adds some nontrivially bigger engines and more fuel, even moreso when you think about landing that extra load, and making the orbiter come back to Earth may or may not need bigger engines but will certainly need more fuel. You could get rid of some of the lander's instrument packages and just process things back home, but that's risking an awful lot on a ton of new things that could go wrong... liftoff could fail, rendezvous could fail, anything could fail along the way home, and there's lots more radiation you have to eat.
On-site analysis is much cheaper and more reliable.
If we all die in 2030 it will sure be a relief we don't have to worry about the year 2038 bug!
"There is more worth loving than we have strength to love." - Brian Jay Stanley
Obama resigned the US to defeat when he cancelled Project Constellation without extending the Space Shuttle program..
That's pretty clueless. Here's why. The Space Shuttle went nowhere after it demonstrated the conditional viability of reusable launch vehicles in the 80s. There's nothing that flew on the Shuttle that couldn't have been more cheaply flown on some other launch system. Further, the money spent on the Shuttle prevented the US from doing a lot of manned and unmanned work.
Constellation was no better for the same reasons. It's also worth noting that Constellation would not have survived competiton with the ULA launch vehicles (Atlas V and Delta IV), if the same cost and safety criteria had been applied to them as were applied to the ULA vehicles. However, the report that supposedly decided things in favor of the Constellation configurations (Shuttle-like stack), did so by deliberately understating risk of solid rocket motors, ignoring thrust oscillation of Ares I, and a few other deep problems of the configuration they chose. Then they came up with a completely bogus risk analysis to justify the choice they made.
We also ignore here that Bush did all the heavy lifting. By the time Obama came in, Shuttle and Constellation were both already walking dead.
SLS is a pale congressional substitute that is still being actively impeded and slow-walked by is cronies at NASA.
Crying shame really since we really need another dead end program to consume all that funding we could have used on real space projects. And it doesn't help that SLS is also underfunded by Congress, the only ones who claim to want it.
Indeed, there was actually a lot that flew on the Shuttle that couldn't have flown on any other launch vehicle - and we're not just talking people and a much more capable deployment system. Between 1988 and 2004 the Shuttle was the highest payload launch vehicle in the world. And the lower end of that range is questionable, as Energia never flew in its heavy lift configuration. In 2004 the Delta IV Heavy came online with slightly more payload capacity than the Shuttle, And really while it "came online" in 2004, its first successful launch wasn't until 2007. The Titan IVB came fairly close to the shuttle's nominal payload (which, BTW, could be increased in certain launch configurations) from 1997 to 2005, but wasn't as large. The same could be said about the Proton M from 1999 onwards and Ariane V from 2002. The Space Shuttle nonetheless had 15% more payload capacity and much more capable launch abilities than these systems (as well as being the only large payload return system in the world that ever operated for more than a few test flights). During the timeperiods these systems weren't available, the next closest systems to the Shuttle in terms of payload had only 3/4ths of its launch capacity.
Part of the reason they kept the Shuttle flying for so long (many had wanted to retire it much sooner) was that there were some ISS modules that could only be launched by the Shuttle.
There were a lot of things that nearly came to be that would have significantly boosted the Shuttle's payload even more, such as the ASRM. They had also started work on the five-segment booster, which would have vastly increased the Shuttle's payload (it's now part of SLS). If there had ever been demand, it had been determined that the payload bay could have been modified into a 30-74 seat passenger area, with a launch cost of 1,5 million USD per passenger (flights per passenger on Soyuz cost $20-40m)
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