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Update on Project Prometheus
Aglassis writes "It appears that NASA is not backing down from their nuclear space initiative. Project Prometheus has recently started a new web page (under JPL) and NASA is finishing up a period of public comment (last session today). Currently Northrop Grumman is contracted to begin preliminary design of the spacecraft until 2008 for NASA (the reactor will be built by the Department of Energy's Division of Naval Reactors--the folks who control all US submarine and aircraft carrier nuclear reactors). Early specs are that it will be 60 meters long, have a 30,000 kg mass, use a 100 KW reactor using Brayton cycle gas turbines, be powered by ion thrusters with a 7000 second specific impulse, and have a science payload of 1500 kg. Early mission plans for Prometheus 1 (Jupiter Icy Moons Orbiter) indicate that the spacecraft would orbit Callisto, Ganymede, and Europa individually, and perhaps have a lifespan of about 20 years."
Disclaimer: I am not a rocket scientist.
In Soviet Rush, today's Tom Sawyer gets high on you.
So they finally figured out how to stabilize naquandria...
Actually, funding for JIMO (Jupiter Icy Moons Orbiter) has been cut.
Finally, we can make some real space vehicles. Fission is the most energy dense technology we have.. it's what we should be using in space. When fusion comes along we may well have something better, but until then we should use what we have.
How we know is more important than what we know.
Wow. Am I the only one that thought the JPL must be some license agreement like the GPL, and the wondered why the hell a web page needed to be released with a special license?
Jet Propulsion Labratory
Portland, North Dakota Puppies
"Does it run Linux?" ... yes, it does. The onboard microcontrollers on the craft will run the uCLinux kernel, with Gentoo userspace. I have no idea what the boxen back at NASA supporting this will run though.
... I for one don't want to welcome our angry alien overlords after they get sick of the crashes :-)
It's a pleasant thought that the first software that aliens might encounter from Earth won't be from M$
"Prometheus Nuclear Systems and Technology will focus on enabling NASA missions by researching and developing nuclear sources that will provide power to innovative scientific instruments and robotic systems, large and small propulsion systems that run on electricity and high-speed communications systems. The nuclear power sources would allow us to extensively explore our closest celestial neighbor, the Moon, as well as Mars and other destinations. Eventually, these power sources would support human explorers as they travel through space and explore other worlds.
= mi ssions
The first proposed mission within Prometheus Nuclear Systems and Technology would be a mission to Jupiter, the Jupiter Icy Moons Orbiter (JIMO), which represents a new class of mission capabilities far beyond those possible with current power and propulsion systems. Powered by a space nuclear reactor and propelled by electric ion engines, the spacecraft would make up-close, long-term orbiting visits to three of the solar system's most intriguing moons- Europa, Ganymede, and Callisto. Beneath their icy surfaces, these moons may contain oceans of water that could have provided an environment that may have harbored life."
http://prometheus.jpl.nasa.gov/index.cfm?pageL1
Beats the heck out of me what that has to do with militarizing space. Besides, IMO, nuclear power is a lot less environmentally dangerous than other power sources except maybe solar energy (which might not work when you're x billion miles from the sun).
--- Grow a pair, liberals... stop letting the Republicans bully you!
http://prometheus.jpl.nasa.gov/contentImages/Blimp _over_Titan211_br.jpg
If that above picture happens in my lifetime, I will drop a load.
I hope they start with something more resonable than this. A big project will get bloated and is less likely to happen. Instead of going to Jupiter, how about getting to Mars with a little more reliability, with people?
Rosco: "If brains were gunpowder, Enos couldn't blow his nose."
what do you think absorbs the readiation from the sun? (hint, its our atmosphere) that big ball in the sky that is the solar systems largest reactor (although its fusion, not fission). Honestly, do you think it's light that heats the earth? no, it radiation. Any radiation from a little spacecraft up in space is miniscule!
What are we going to do tonight Brain?
than the real progress NASA makes.
IMHO, it's a real shame projects like these aren't far more international in scope, open to all bidders, and funded from a futures type trust and traditional venture capital funding, as well as grants and taxes. Heck, most of these projects will pay back in spades if the new technologies were only properly licensed.
It simply amazes me how we have so many business geniuses, but not one of them has even considered space as the next new continent. What ever happened to good old American ingenuity and initiative, eh? Why have we apparently just given up our collective dreams of space exploration and development? Any one care to explain?
Words to men, as air to birds.
"It appears that NASA is not backing down from their nuclear space initiative."
It'll still be lifted off the ground by chemical rockets. What happened to NERVA?
We used it in WWII.
And Iran would be pacifist if we never got involved in their history. They had a moderate government with some elements of capitalism. But then the USA decided to help Hussien, we sold him all the arms he needed to attack Iran for over a decade. And we let the Shah get expelled, for a very rigid Kohmeni.
Rosco: "If brains were gunpowder, Enos couldn't blow his nose."
I don't know the ins and outs but I'd imagine that if you have a nice chirpy nuclear-reactor to generate power, taking photovoltaics (solar panels) with you too would be rather pointless. - PVs would cost extra to put into space to start with and would also need trickery to align them with the sun.
Having glanced at the picture, I'd suggest it is more likely that the big flat panels are heat dissipators (heat-sinks) to get rid of the excess heat from the nuclear reactor. I presume that in space there is no conduction of heat away from the vehicle, only radiation. And that you improve the radiation of heat by increasing the surface area.
Ripping an new rectum in the fabric of spacetime.
Light is, of course, radiation.
That said, I'm happy it never really materialized. Having a universe with a human population spreading effectively in it summons an eerie image on a spherically expanding brain-tumor to my mind...
http://isbndb.com/d/book/project_orion.html
Our local observatory (with live night-sky camera) is Gummint-funded. This leads to some interesting effects.
Much of their computing equipment has been scrounged - and doesn't appear on any equipment manifests - because there was no budget for it. They have a Pentium-90 driving (pointing) their main 'scope with a backup P-90 literally sitting on the next shelf in case it dies.
The few pieces of gear that they do get grants for are typically extremely fancy. On the rare occasions when ThePowersThatBe say "yes, you can have a computer to process the incoming images," then the cost of that actual computer system and absolutely nothing else is almost immaterial as long as it fits certain criteria.
So... in the room to the left of the one housing the P-90 sits a you-beauty glow-in-the-dark (well, not literally, it would cause backscatter) state-of-the-art box with double overhead ThermalTakes and all the trimmings. Just one. And I bet they crammed memory and disks into that baby's purchasing spec until the chassis groaned under the weight.
When Mark Shuttleworth gave his amazing talk at LCA2005, one of the things he mentioned was that the Yanks didn't want their astronauts (also going up in the Soyuz with Mark) flying to Baikonur in a rattly old Tupelov transport lest it unexpectedly drop out of the sky en route, but rather than come out and say so directly they came over all clever and simply pointed out that NASA regs forbade their astronauts to travel without seatbelts, which they knew the Tupelov wasn't fitted with. This was a mistake. On the day, the astronauts were marched out to the Tupelov, and aboard - and into a minibus in the cargo bay, where they sat and wore the minibus's seatbelts for the duration of the trip.
BTW, when the video DVD from LCA2005 gets published, bend heaven and earth to get yourself a copy. It's well worth-while for Mark's presentation alone ("Welcome to Khazakstan!"), and there are many other excellent presentations on it (Keith Packard explaining the sport of Window Hurling, for example, or E'dale demonstrating how to collapse a penguin's skull).
The point in that story which I wanted to use as an illustration here was that the minibus wasn't put aboard the transport for the astronauts' benefit. There was a budget for flying the Tupelov - pilots, fuel, landing fees and so on - but no budget for getting from the airport to where they were staying. So the van (which fell under the base's budget, so was financially covered) was fuelled up and driven aboard the Tupelov for use as a taxi while the transport 'plane was prepped for the return flight. In terms of working around bizarre regulations, NASA or not, the Americans really were amateurs playing in a professional field. (-:
Got time? Spend some of it coding or testing
Because this reactor will be designed to be in a rocket explosion. It will be launched before it goes critical. it wont even be turned on, and cant be turned on, until it is safely in orbit. Beyond that, there is alot more nuclear material in your nighborhood reactor than there will be in this thing.Not only that, but NASA launches over the ocean, water is a very good radiation shield. Thats why there are several nuclear submarines lying on the ocean floor that you arent worried about.
In case you didn't realize, Uranium is the 8th most common material on the planet... Taking a few tons off of it won't do any good. There's enough uranium to last the damn planet for the next 2000 years at least. Don't argue with me, I researched the damn thing two months ago. :)
Due to financial difficulties, the light at the end of the tunnel has been turned off.
are you implying that a 100kw fission reactor in orbit presents an exposure concern to personnel? i hope you are joking. assuming average prompt gamma ray energy is 1 Mev, the reactor has NO shielding, 1 Ci of a 1 MeV gamma ray point source produces an exposure rate of 1R/hr at a distance of 1M, all of the energy is emitted from a point source, and the reactor acts as a 100,000 Ci point source(this should be conservative, someone with more knowledge might upgrade me on this?), then(neglecting backscatter buildup): DR @ 1m = 100,000R/hr DR @ 10m = 1000R/hr DR @ 1km = 0.1R/hr DR @ 100km = .01mR/hr
365 days * 24hr * .01mR/hr = 87.6 mRem(assuming 1 as a QF, i can't recall the QF for a 1MeV gamma flux right now).
assume the reactor and craft present 1 tenth thickness of shielding(should be conservative): 8.76mrem
assume the atmosphere presents 3 tenth thickness of shielding(again conservative): .00876 mRem
this craft in orbit(realizing it will not remain there) would, conservatively, increase the average persons natural radiation exposure by less than one thousandth of one percent.
this is simplistic but AFAIK conservative.
On a related note, a few words about nuclear rockets. Back in the 50s and 60s some people, mostly science fiction writers, fantasized about nuclear powered rockets. In the 60s there was an actual prototype engine called NERVA. The idea was simply to use the reactor as a heat source to superheat a gas which would shoot out as rocket exhaust. The main drawbacks were the weight of the reactor core, the maximum temperature of about 3500 degrees C, and the radioactivity of the exhaust.
Here's a really interesting article that describes a design for a 100% reusable, non-polluting nuclear rocket based on the Saturn V form factor, capable of lifting 2 million pounds of cargo into orbit and returning to a soft landing. Just like in the old sci-fi movies. The design involves a gaseous core reactor, sometimes called a "nuclear lightbulb." It consists of a quartz bulb containing a cloud of uranium gas such as uranium hexafluoride, confined the center of the bulb by a buffer gas swirling around it. By adjusting the movement and pressure of the buffer gas, the compression of the UF6 can be finely regulated. When it is compressed to a critical state it heats up to about 25,000 degrees C, glowing intensely in the ultraviolet. Liquid hydrogen propellant pumped around the outside of the quartz bulb absorbs the ultraviolet light, becomes superheated, and shoots out of the nozzle. There is no leakage of radioactive fuel and no irradiation of the hydrogen. Completely clean burning. Such a rocket could burn for immensely longer times than any chemical rocket, providing the speed to get a manned mission to mars in a couple months. And not a skimpy mission, a spacious vehicle carrying 1000 tons of equipment, supplies and radiation shielding. Building a rocket like this wouldn't require any far-fetched technology, just some dedicated engineering.
I have never been a fan of nuclear reactors, but this thing sounds really good to me. The gaseous core has tremendous safety advantages over a solid core. The criticality of a cloud of gas is much easier to control and is to some extent self-regulating. For example, the problem of "hot spots" would not exist, because in gaseous form any part of the UF6 that overheated would expand, losing pressure and quenching itself instantly. The author describes several safety features, both active and passive, for letting the gas depressurize into a storage container extremely fast. Even if a gas core nuclear rocket exploded in the atmosphere, it would release a small fraction of the amount of nuclides from a single 1950s H-bomb test.
that's right, George, there's rivers and rivers of LIQUID HYDROCARBONS down there, and America's got the mineral rights!
No, the correct answer is: the US is already a declared nuclear state and the continued manufacture of nuclear weapons is therefore not a violation of the Non-Proliferation Treaty, which pretty much says "If non-nuke states don't build their own bombs, nuke states will help them build reactors." What Iran is doing is outside the bounds of the treaty.
Besides, when you already have several thousand fusion warheads, why build more?