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Delaying Our Visit To The Last Planet
O.F. Fascist writes: "Story over at Space.com about how the first NASA mission to Pluto might get cancelled for a variety of reasons." Sounds like the reasons at play here are good, though -- "reliable transport required" applies to multi-year interplanetary journeys, too. (And what are we looking for on Pluto again?)
Cheetos.
Pluto is speculated to house the world's largest naturally-occuring supply of Cheetos, which due to it's unique chemical and thermal conditions occur in both original and crunchy varieties.
Of course, Cheetos are just the easiest Plutonian resource for us to extract. Researchers have speculated that there may be literally millions of Brittany Spears CDs, Teletubbies dolls, and other objects of highly marketable value to our advanced society.
Of course, there is some concern that we'll have to scrape away layers of frozen methane, abstract scientific research, technological challenge, impact crater detrius, and new knowledge of our universe, before we can get to even the most shallowly buried N'Sync singles; but isn't it worth it to try?
Christopher A. Bohn
cb
Oooh! What does this button do!?
And what are we looking for on Pluto again?
Put a server farm out there, use heavy encryption, et violá! instant data haven. Let the FBI try to seize that! Of course, a half-day transaction latency could be a problem, but faster than lightspeed communication is just around the corner, right?
And what are we looking for on Pluto again?
Exactly what we've been looking for on all the other planets. Some sort of Amazon society. Standard operating procedure is that we send a team of astronauts (they must have names like "Duke" or "Buzz") onto the planet. They are captured by the warlike Amazons. While imprisoned, the Amazon leader's daughter falls in love with Duke (or Buzz), helps them escape, and they take off in their rocket back to earth.
I hereby volunteer for the mission.
And I'm changing my name to Duke (or Buzz).
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This isn't Pu-239, the isotope that is used in nuclear weapons. We have huge amounts of Pu-239. Radioisotope Thermoelectric Generators (RTG) use Pu-238, a plutonium isotope with a much shorter half-life (87.7 years). The problem is producing the material. Pu-238 was produced by the Department of Energy as a byproduct of the nuclear weapons materials production infrastructure, which has largely been shut down. There has been discussion of restarting a capability to produce Pu-238, but I'm not sure if any progress has been made. There are plenty of anti-nuclear know-nothings who are opposed to the idea.
Mea navis aericumbens anguillis abundat
Pluto/Kuiper Express (PKE) was to be one of three JPL solar system exploration missions. The other two include Europa Orbiter (intended to determine the existance of a subsurface ocean), and Solar Probe (intended to determine the origin of the solar wind). PKE's purpose was to image Pluto and Charon (Pluto's moon) and a Kuiper Belt object. EO's biggest challenge is it's complex orbit insertion. SP, of course, has to deal with an intense thermal environment.
PKE's principle challenge was to reliably conduct an autonomous encounter navigation after spending 8 years travelling out there. The craft would be zipping past Pluto at a good clip, and clicking a few pictures (for later transfer back to earth) would be tricky - gotta have the camera pointed in just the right directions at just the right time.
The reason autonomy is necessary, is that at Pluto, the round-trip time for a beam of light to travel between Pluto and ground control is 8 hours, but the entire Pluto encounter only lasts a few hours.
Another problem, mentioned in the article, is that finding a launch vehicle with sufficient performance to get enough mass (a few hundred kg's) going on an accurate trajectory, is pretty tricky.
I think it'd be a pretty cool mission, although I can understand why NASA may prefer to direct their funds towards other projects that would return larger amounts of results for less risk. I hope this doesn't mean Europa Orbiter or Solar Probe are also in danger of cancellation.
Uhhhh... interesting statement, but I have to disagree. When Clyde Tombaugh discovered Pluto on February 18, 1930, he was searching for a ninth planet predicted to exist because of discrepancies between the predicted and actual orbits of Uranus (and Neptune) -- the precise reason that the planet Neptune had been discovered, in fact (here's a detailed story of the whole affair). At the time, no one had any notion that Pluto would be so small: it was predicted to be between two and seven times the mass of Earth, and everyone expected it to be dim -- why else would it be so hard to find?
As it turned out, the most likely cause for Uranus and Neptune's orbital discrepancies is probably observational error, and Pluto just happened to be in the approximate neighborhood being searched. If it were discovered today, we might not call it a "planet" -- it's only the largest (so far) of a number of objects in the Kuiper belt -- but this has been the subject of a lot of controversy, and it's been officially decided to keep calling it a planet.
At the time it was discovered, no one had any notion that things would turn out this way, so it was just considered a planet and named as such. No special considerations or rewards -- just ignorance of the future, as always...
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Politics is about making compromises. Religion isn't. --Michael Horton
The issues surrounding PKE have mostly to do with large budget squeezes within NASA, with the long flight time, and with the radiothermal generator stuff. No need to spout about the reasons why the budget is tight -- though astute people will recall that there's some sort of orbital treehouse that's a leetle bit over budget. It's also hard to justify now spending a bunch of money that can't conceivably pay off until after the next president's term is over -- the flight time to Pluto is >8.5 years. (That sounds like a long time, until you realize it's taken over 12 years just to get the project from NASA HQ outside the Capitol Beltway.) Other folks have pointed out that, due to the unexpected outbreak of world peace, there's comparatively little nuclear weapons development going on -- and hence not much Pu-238 to be had. Further, all the reactionaries who tried to prevent the Cassini launch (did any of them actually bother to calculate the worst-case release scenarios?) are still around, and now they're mad as Hell. The protests and legal action tripled the cost of the RTGs in Cassini, and PKE will have similar problems.
Solar Probe will have trouble with Pu as well, but at least that mission has an alternative. Solar panels, oddly enough, won't work -- they'd get too hot to work around Mercury's orbit, and melt a few days after that. The current plan has a couple of different solar flybys happening -- that requires RTGs, which will last long enough to do the job. But NASA could back off to a single-flyby mission. Then a jettisonable set of solar panels would be used during cruise phase. During the flyby, power would be supplied by a bank of chemical batteries. But then the probe would be dead, dead, dead shortly after the last data from the flyby were downlinked to Earth.
Both of these spacecraft concepts would require incredible miniaturization. Our proposal (I helped write one submitted by Southwest Research Institute) has instruments that are about the size and mass of full beer cans.
That type of statement is the reason NASA's budget has been cut so drasticly over the years, which directly led to the high-profile failures of some of the recent Mars missions. We're not looking for anything in particular; the whole point of a mission such as this one would be pure exploration - we don't really know what to look for, so you have to begin somewhere. It's true that there will never be (in our lifetime, at least) any commercial value from the exploration of Pluto, but does that mean we shouldn't go there? If that kind of test were applied to all matters of exploration and research, we'd still be in the dark ages.
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http://gammatron.weblogger.com
Okay, that's it. You guys aren't real nerds. Time to change your slogan.
Somehow I suspect that this Plutonium "shortage" has more to do with fear of another political flap, like the one surrounding the launch of the Cassini probe (oh my god, they're launching *Plutonium*... on a rocket!).Science shouldn't always have a direct application or use. It's their because once in a while it creates something amazing, that changes everything and affects everyone. You can't always directly apply science to solve a need. Sometimes you don't know a need was there until it has been satisfied.
I mean we still don't know what (if any) atmosphere exists around pluto. Knowing the material composition would tell us more about where Pluto actually came from, like was it formed at the same time as the rest of the solar system or was it just a BIG comet...
Why do we study any of the planets, why do we look for bones in the ground that are a few million years old? We know Dinosaurs exitst, I guess for some people that's enough infomation.
"People of Earth. Welcome. .. or was it miles?.
Please come to our planet.
We are only 5,913,520,000 mil^H^H kilometers from the sun.
er ummm
Nevermind."