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Cassini's First Glimpse of Saturn
EccentricAnomaly writes "The Cassini spacecraft has snapped its first picture of Saturn from 177 million miles away. Cassini is due to arrive at Saturn in July 2004, becoming the first spacecraft to orbit Saturn (Pioneer 11 and Voyagers 1 and 2 just did quick flybys of Saturn). Cassini carries the Huygens probe which will land on Saturn's moon Titan in January 2005."
Woo Hoo! Those 72 pounds of plutonium have almost reached their destination. Those thrice accursed Satunians won't know what hit them! And we also have a little surprise for those shifty little Titans too...
If Mr. Edison had thought smarter he wouldn't sweat as much. --Nikola Tesla
Isn't that enough?
...if the Cassini already flew by Earth?
I remember a few years ago (1997?) that there was a lot of talk about this, because it carried an atomic fuel cell, and it was sopossed to fly by the Earth in some years to gain speed due to the Earth's gravity. Ecologists were going wild because it would come so close to Earth. Well, if it's so close to Saturn it probably means it all went fine.
please excuse my apathy
I don't know Columbus, this new world thing is cool and all, but, we have so many problems here in Spain...Shouldn't we solve those first? I mean I have no problem with explorer playing with the crown's money(peoples' taxes), but shouldn't the aristocrocy (and the people) get something out of it as well??
Yes it's true. I'm a janitor at the NASA Goddard facility in Greenbelt, MD. I was having a smoke one day at the loading dock at building 33. I was sitting down kinda hidden behind a recently arrived crate. Two scientists came out to have a smoke. They mustn't have seen me because they began heatedly discussing whether to use a beowulf cluster of linux boxes or winNT boxes to generate all the fake images they would require to pull off the "casini hoax". There were also a whole series of rumours, too numerous to recount, about this and many other NASA hoaxes at the Goddard facility.
The lighting of pictures taken in space requires an f stop setting of the camera that makes the stars invisible. Photographs taken of the Saturn don't show stars because the bright light (reflective) of Saturn requires camera settings which make the stars invisible.
All the worlds indeed a
Off the otp of my head, I'd have to guess that the stars aren't in that picture for the same reason there are no stars in the pictures from the apollo moon landings. The astronaut's suits were made to be very reflective, and with little to no atmosphere to filter the light from the sun, the astronauts would be very bright. In order to capture the bright object on film, the shutter rate on the camera would have to be set very fast. For this reason the relatively dim stars in the background didn't have time to take their place on the film.This is probably the same for the picture of Saturn. For a real life comparison, imagine looking straight into very bright light (spotlight, etc.), you won't be able to see anything behind it or to it's sides, because the light is so bright. It's somewhat similar to that.
I feel guilty every time I boot Windows
The parent asks about the portion of Cassini's trajectory which passed very close to the Earth. On August 18, 1999, the spacecraft swept past the Earth at a minimum altitude of just over 700 miles. You can read about it here:
http://www.jpl.nasa.gov/releases/99/csearthflyby.h tml
Why fly so close? The JPL team arranged it so that Cassini went past the "back" side of the Earth. The earth circles around the Sun at a pretty good clip (about 30 km/sec). Cassini came towards the Earth from behind in its orbit. The gravitational force of the Earth on the spacecraft pulled it forward, speeding it up as it went by. By the same token, the spacecraft slowed the Earth down a little bit, but by an insignificant amount. This is one of the two sorts of "gravitational slingshot" manuevers the celestial mechanics can use to give spacecraft more speed without using lots of fuel.
Simple analogy: stand on a sidewalk as cars drive past at 30 mph. Just as one car is about to pass you, toss a tennis ball out in front of it. The collision will greatly increase the speed of the tennis ball in the direction of the car's motion (and only very slightly decrease the speed of the car). We can't bounce spacecraft off the Earth in the same way :-), but we can use gravity to pull spacecraft forward in a much gentler manner.
For information on the risks associated with the flyby, please read
http://a188-l009.rit.edu/richmond/answers/cassini. html
Michael Richmond "This is the heart that broke my finger."
mwrsps@rit.edu http://stupendous.rit.edu
Today the Kronos observatory managed to snap its first picture of Cassini. Cassini is a piece junkyard which Earthlings call "spacecraft". It will be their first attempt to orbit our planet, after their surreptical flybys almost an year ago. According to sources they will attempt to crash a small probe in Titan. Official sources at Titan colony consider a very remote possibility that this thing will fall on someone and call the mass media to stop the hype about this:
"The most probable is that this thing will burn up in the atmosphere. Besides there is some assurance that Earthlings will buzz around a little, make some fuss out of it and calm down for the next years, or centuries in Earth's terms. So we decided not to interfere on this things a get them a little happy for having a glimpse of our homeland... Anyway, I may assure you that we will not see tourists storming our beautiful landscape and poisoning our nature... However these guys have some sickening curiosity and if we stop them right now, we can see something similar to our Mars cousins were they frequently crash one or two probes every year. We surely don't want to see this happening every month here..."
That little white pixel is Saturns largest moon Titan - If you read the link you will find that this was a test of the camera (A monochrome camera shot through various color filters) depending on the aperature of the camera, the integration time, and any image processing routines the stars were lost most likely due to the fact that Saturn is such a bright planet - I am sure that if they adjusted the image to see the stars the image of Saturn would be saturated and just a bright blob.
OK, so how come we can't get a train or bus to arrive in time? It's a much shorter distance and scaled down, we should be able to get millisecond accuracy across town. Do we need rocket engineers designing buses and astronauts driving them?
Money for nothing, pix for free
Awesome. I love seeing stuff like this. One day people on earth are going to need to put "Earth" on the last line of their addresses. And we'll have a planet code for earth to dial before the rest of the phone number. Maybe then earth will become more harmonious as people feel there is more to life than their own little world, literally. One day I tells ya!
but that -178 Celsius surface temp sure puts a damper on things.
Huygens (Christiaan thereof) was the Dutch physicist/astronomer who came up with the wave theory of light. He also used a telescope to study Saturn's rings and also discovered one of Saturn's many moons. He lived in the 17th century, although I'm not exactly sure of his DOB and DOD, because I'm too lazy to look.
Giovanni Cassini was another who studied the rings of Saturn. He found a division between the rings, aptly named the Cassini Division, and also discovered several (four, I believe) new Saturnian moons.
I'm sure this will help connect Huygens, Cassini, and Saturn.
I'm the Devil the Windows users warned you about.
I believe the actual concern everyone had about Cassini flying by earth is not that it woud slow the planet down, but that Cassini uses Nuclear Power and an accident would, uh, suck.
There are two kinds of people in the world: Those with good memory.
I'm sure it didn't really happen like that, but this would be a funnier account of history, and that's what matters to me.
Results from conducting my experiment.
stand on a sidewalk as cars drive past at 30 mph. Just as one car is about to pass you, toss a tennis ball out in front of it. The collision will greatly increase the speed of the tennis ball in the direction of the car's motion (and only very slightly decrease the speed of the car)
07:45AM Looking for tennis balls.
07:57AM Finished wrestling dog for three tennis balls from the backyard. They appear to have been well chewed and soaked with dog slobber. Given daily high temperatures of 18 degrees (F) over the past week, these objects more closely resemble croquet balls than tennis balls...Oh well, technically I'm within the experiment's parameters. Cool.
08:15AM Observed six candidate cars outside of the house, but given icy road conditions none appear to be travelling at greater than 20mph.
08:30AM The dog and I took a walk over to the state highway about a mile away. The vehicles here are definitely meeting the minimum speed threshold outlined in the experiment parameters. I can't find a sidewalk adjacent to the highway, but the overpass above it does have a sidewalk. I'll use that one.
08:35AM Identified first candidate vehicle, a small four door passenger car. I completely mis-timed the drop from the overpass and missed the vehicle entirely. The dog is not impressed.
08:40AM Identified more appropriate candidate vehicle - a semi-truck with a large windshield. Perfect.
08:42AM Upon making contact, the ice laden tennis ball failed to greatly increase it's speed in the direction of the vehicle. It actually pierced the windshield of the truck (on the passenger side). The vehicle's speed was quite substantially decreased as the truck jacknifed on the highway. Additionally, over a dozen other vehicles experienced a similar high decrease in speed as they hit the now halted truck. I have obviously disproved a commonly accepted scientific principle!!!
11:23PM The dog and I remain in the custody of the local law enforcement authorities. I now understand how the imprisoned Galileo felt when he knew his experiments disproved prevailing accepted scientific principles.
Conclusion
I am determined to persevere in the name of scientific accuracy. Look for me on the next overpass you drive under and help support my search for the truth!!
public works and government programs are defn. useful things, but to discount *knowledge* as a potential payoff from scientific discovery is shortsighted. honestly, this taxpayer would gladly see some pork barrel spending diverted to NASA (or education, or welfare to work programs).
smd4985
they think Titan may have a suitable atmosphere to support human life
Would that be the same "they" who think the earth might be hollow?
-
- - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
Actually, no. Titan's atmosphere is believed to consist mostly of hydrogen and methane. It would be poisonous and unpleasant for human beings. However, both chemicals are useful organic building blocks, and Titan's surface may resemble a colder version of Earth's primordial soup, which makes it a valuable area for study.
THE GOOD HUMOR MAN CAN ONLY BE PUSHED SO FAR
Bart Simpson on chalkboard in episode 2F18
Eventually we'll be able to send nanobots to Saturn's moon at which point the bots can reconstruct whatever we want.
Of course NASA will fail to run a virus scan before launch and we'll end up with a huge robot the size of Saturn's moon heading towards earth for its next meal.
>> know this is cool and all... but still... we have so many problems on our own earth... shouldn't we solve those first?
....How do I say this??
In my view it's good for mankind that we do stuff like this despite all our little 'tribal warfare' related problems. Maybe, just maybe as more discoveries are made out there, Mankind will embrace a sense of wonder.
If Mankind can become enlightened enough to see that there's a whole universe out there to explore and learn about, maybe fighting over rocks(land) and colored rags(flags) and who's god is better, will take a back seat to a drive to do things for everyone's good.
Like put effort into making discoveries that will cure more diseases, and educate our people further, and give us the foundation we need to jump to the next level.
Can you imagine what we could accomplish if we were all pulling together instead of threatening to nuke the shit out of each other?
We really need to wake up & see that there are bigger and better things than our puny little planet out there.
And if we don't get our act together soon mankind will probably never have the foundation/knowledge to set foot on another planet, or get a suntan from another star.
Myself, I feel really inspired when I see new pictures like this. It makes me want to work harder at what I do, and it makes me wish that we could all stop fighting and go outside and look at the sky.
Huh?
A one legged robot floating in the rings.
(Resolve that obscure reference, I dare you!)
Hell no!
All these worlds are yours, except Europa... ATTEMPT NO LANDINGS THERE!
What are you, crazy?
I've had enough abrasive sigs. Kittens are cute and fuzzy.
It is indeed the exposure - much too short to show stars. (These cameras do not have shutters to stop down.)
Late this year they will also start to do optical navigation - or optnav - which takes long exposures to show stars relative to the limb of the planet or a satellite. This relative spacecraft-star-planet information is a very valueable addition to the one dimensional range and Doppler (radar) information that spacecraft navigation relies upon.
Generally in opnav pictures the planet or moon is totally over-exposed, but this is how Linda Morabito discovered the volcanic eruptions on the Jovian moon IO - an enourmous fire fountain silhouted against the darkness of space - so you never know.
Because of their poor visual quality, optnav pictures are almost never released to the press.
There used to be plans for a whole set of Europa probes - first an orbiter, then landers to use seismographs to determing the thickness of the crust and whether there's water down there, then eventually a submarine... Sadly, this all seems to have been cancelled.
The NASA page about the Europa project is still there, and loads - momentarily - before redirecting you to their updated site, from which all references to Europa seem to have been expunged...
Incidentally, there might be less confusion if you call them 'Europans' rather than 'Europeans'. There are about half a billion Europeans already, and we don't live anywhere near Jupiter.
Real Daleks don't climb stairs - they level the building.
PR, but what's the use? Detailed pics of Saturn and rings, yay, but nothing we don't have. Although, the huygens probe actually looks useful, I think NASA should be more ambitious.
Pretty pictures of Saturn are the least of what's coming back. Go to the mission objectives page for the probe to see all of the experiments that will be done.
What, exactly, do you _want_ them to do? Bear in mind that sending humans *anywhere* costs at least 20 times what a probe with comparable scientific capabilities costs.
Also since Cassini is still far from Saturn the field of view of the image is quite small. It's unlikely there would just happen to be a bright star in that narrow field of view.
Cassini reminds me of a time that many slashdotters may never have experienced. (I am almost 40)
As a young person in K-12 school NASA projects implied an expectation level of what was possible and expected of engineers. Seeing the results of Apollo, Voyager, and Viking on every magazine and nightly newscast caused me and my friends to assume that every engineering meeting in the USA went something like this...
ProductGuy : Lets put two fully functional chemical analysis and weather observatories on the surface of Mars and send back the data to Earth. We don't have a map of Mars and we will not know where to land them on Mars until we get in orbit.
Engineering Team: OK, lets do it.
It was subtly drilled into our adolescent minds that American Engineering could accomplish anything. And we always noticed the US flag that was in most pictures of the spacecraft and landers.
Today I write software the exact way that Bill Gates wants me to but I am amazed at how everyday I hear from young coders is whining words like "That's hard", "I don't want to", "That will make me have to think." If I had ever responded like that when I was younger the comeback answer was always "We put a man on the moon, surely you can do (insert trivialized task here)".
Cassini reminds me of that 1970's NASA for some reason. Not the NASA that sent a small tinkertoy to Mars in 97 for a few photographs of rocks.
Just to clarify, every scientifically informed person in 1492 knew that Columbus's plan was baloney. There is no way he could have reached Asia, and everyone else knew it. If the moron hadn't lucked into this huge continent of America lying across his path, he would have failed miserably. His wasn't some carefully planned scientific expedition, it was a crackpot sailor charging at a windmill.
Columbus quoted the smallest diameter of the earth that he could find, and the largest extent of Asia that he could find, and even if both were true, he barely would have made it.
The mission that Columbus sent on was pretty damn cheap, and was pretty much given to him to get rid of him.
Similarly, every scientifically informed person knows that there are few real science experiments that can be done on the International Space Station that serve any purpose other than figuring out how things behave in space stations. But, we continue to do it as a pork-barrel subsidy for the aerospace industry, while clueless Slashdotters claim that this is a great thing for preparing for future space colonies, or some other malarkey.
Justify Cassini on scientific grounds, or on entertainment grounds, not on some nonsense like "Exploration is inherent in our nature." So is violence. Luckily, we have, to some small degree, the power of reason, so we can rationally decide when our "inherent nature" should be followed or not.
maybe it can support other non-carbon based life forms. that'd be really interesting.
--- check this alien conversation out, worth the read. stolen from: http://www.setileague.org/articles/meat.htm ---
"They're made out of meat."
"Meat?"
"Meat. They're made out of meat."
"Meat?"
"There's no doubt about it. We picked several from different parts of the planet, took them aboard our recon vessels, probed them all the way through. They're completely meat."
"That's impossible. What about the radio signals? The messages to the stars."
"They use the radio waves to talk, but the signals don't come from them. The signals come from machines."
"So who made the machines? That's who we want to contact."
"They made the machines. That's what I'm trying to tell you. Meat made the machines."
"That's ridiculous. How can meat make a machine? You're asking me to believe in sentient meat."
"I'm not asking you, I'm telling you. These creatures are the only sentient race in the sector and they're made out of meat."
"Maybe they're like the Orfolei. You know, a carbon-based intelligence that goes through a meat stage."
"Nope. They're born meat and they die meat. We studied them for several of their life spans, which didn't take too long. Do you have any idea the life span of meat?"
"Spare me. Okay, maybe they're only part meat. You know, like the Weddilei. A meat head with an electron plasma brain inside."
"Nope. We thought of that, since they do have meat heads like the Weddilei. But I told you, we probed them. They're meat all the way through."
"No brain?"
"Oh, there is a brain all right. It's just that the brain is made out of meat!"
"So... what does the thinking?"
"You're not understanding, are you? The brain does the thinking. The meat."
"Thinking meat! You're asking me to believe in thinking meat!"
"Yes, thinking meat! Conscious meat! Loving meat. Dreaming meat. The meat is the whole deal! Are you getting the picture?"
"Omigod. You're serious then. They're made out of meat."
"Finally, Yes. They are indeed made out meat. And they've been trying to get in touch with us for almost a hundred of their years."
"So what does the meat have in mind?"
"First it wants to talk to us. Then I imagine it wants to explore the universe, contact other sentients, swap ideas and information. The usual."
"We're supposed to talk to meat?"
"That's the idea. That's the message they're sending out by radio. 'Hello. Anyone out there? Anyone home?' That sort of thing."
"They actually do talk, then. They use words, ideas, concepts?"
"Oh, yes. Except they do it with meat."
"I thought you just told me they used radio."
"They do, but what do you think is on the radio? Meat sounds. You know how when you slap or flap meat it makes a noise? They talk by flapping their meat at each other. They can even sing by squirting air through their meat."
"Omigod. Singing meat. This is altogether too much. So what do you advise?"
"Officially or unofficially?"
"Both."
"Officially, we are required to contact, welcome, and log in any and all sentient races or multi-beings in the quadrant, without prejudice, fear, or favor. Unofficially, I advise that we erase the records and forget the whole thing."
"I was hoping you would say that."
"It seems harsh, but there is a limit. Do we really want to make contact with meat?"
"I agree one hundred percent. What's there to say?" `Hello, meat. How's it going?' But will this work? How many planets are we dealing with here?"
"Just one. They can travel to other planets in special meat containers, but they can't live on them. And being meat, they only travel through C space. Which limits them to the speed of light and makes the possibility of their ever making contact pretty slim. Infinitesimal, in fact."
"So we just pretend there's no one home in the universe."
"That's it."
"Cruel. But you said it yourself, who wants to meet meat? And the ones who have been aboard our vessels, the ones you have probed? You're sure they won't remember?"
"They'll be considered crackpots if they do. We went into their heads and smoothed out their meat so that we're just a dream to them."
"A dream to meat! How strangely appropriate, that we should be meat's dream."
"And we can mark this sector unoccupied."
"Good. Agreed, officially and unofficially. Case closed. Any others? Anyone interesting on that side of the galaxy?"
"Yes, a rather shy but sweet hydrogen core cluster intelligence in a class nine star in G445 zone. Was in contact two galactic rotations ago, wants to be friendly again."
"They always come around."
"And why not? Imagine how unbearably, how unutterably cold the universe would be if one were all alone."
Columbus's trip actually had a justifiable business purpose - he was looking for a more economical trade route to India (hence the whole "indians" misnomer that's plagued us ever since). My understanding - which may be incorrect on a few points - is that it was well-known by the aristocracy that the earth was round (and so that such a trip was theoretically possible), but it was thought that the ships of the time wouldn't be able to make such a long trip (and they might have been right; Columbus only had to make it part way around before finding the New World).
Space exploration is blue-sky research. It does not have a strong business case for it. That doesn't mean it shouldn't happen; it just means that it's unlikely to ever be directly profitable.
Possible justifications include:
I personally feel that it is in our best interests as a species to have a good understanding of space and to exist on multiple worlds (as our outlook for surviving in geologic time at any single location is not so good). This, in addition to it being cool and stimulating R&D, justifies it as far as I'm concerned. YMMV.
Well, *I* sure as hell don't want a picture of uranus.
*runs too*
Moderation: +4. Modded 70% Funny and 30% Overrated. 100% Saturated.
Actually, no. Titan's atmosphere is believed to consist mostly of hydrogen and methane.
Actually, no. Titan's atmosphere is mostly nitrogen and then methane.
Any hydrogen that's there comes from methane dissociation and quickly escapes Titan's gravity. However, the hydrogen atoms can't escape Saturn's gravity and form a hydrogen torus along Titan's orbit. There should be some interactions between the torus and Saturn's magnetosphere which Cassini will observe.
Mod this guy up...it halarious!
Moderation: +4. Modded 70% Funny and 30% Overrated. 100% Saturated.
It looks to be a fairly small image, which makes sense as the spacecraft is 177 million miles away from the planet. I think it would be interesting for the spacecraft to take one such picture a day, then put them all together some years later to produce a movie of the spacecraft's mission.
I'm sure it would beat the cgi movies that have been produced of similar journeys.
This is an ex-parrot!
we have so many problems on our own earth... shouldn't we solve those first?
Our destiny *is* out there. We better get familiar with it. The "Mores Law of Terrorism" is that the number of people a small group of terrorists can kill doubles every X years. Eventually they will be able to wipe out most of the population and perhaps all using nukes, chemicals, mad cow desease, etc.
We can't keep all our eggs in one basket forever. We will have to colonize space and other planets to ensure survivle of the human race.
Table-ized A.I.
No, an accident would NOT suck.
An accident would suck - $3.2billion down the drain - for a nice firework in the night sky
One of my favorite quotes:
"Cutting the space budget really restores
my faith in humanity. It eliminates dreams,
goals, and ideals and lets us get straight
to the business of hate, debauchery, and
self-annihilation."
-- Johnny Hart
"You cannot have a General Will unless you have shared experiences. You cannot be fair to people you don't know."
Space exploration is blue-sky research. It does not have a strong business case for it.
I don't know what you mean. Once we build the trillions of dollars of equipment and launch a number of billion-dollar missions, we will be able to bring back millions of dollars worth of ore from celestial bodies. The VCs should be waiting to jump all over this.
In order to have a really useful space station, something that doesn't have an insanely high operating cost, it must be large. NASA, stop throwing away booster tanks; Take them to the ISS and duct tape them together if you have to. They're useful.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Photographs taken of the Saturn don't show stars because the bright light (reflective) of Saturn requires camera settings which make the stars invisible.
But still, they should GIMP (or Photoshop) the stars into the picture in order to placate the consipracy theorists.
...stars were lost most likely due to the fact that Saturn is such a bright planet - I am sure that if they adjusted the image to see the stars the image of Saturn would be saturated and just a bright blob.
There's an even more detailed explanation of this phenomenon at the Bad Astronomy web site, in the section where research astronomer and part-time hoax debunker Phil Plait explains in great detail why there are no stars in the pictures from the moon. Plait debunks the Fox TV least-common-denominator showcase "Conspiracy Theory: Did We Land on the Moon?" point by point... too bad the rubes the show was targeted to probably can't figure out that "Internit thang" anyway.
Stressed? Me? Of course not. Stress is what a rubber band feels before it breaks, silly.
You could make the space program immediately profitable by putting up a real space station.
How?
Such a station could certainly be built, but how would it generate enough revenue to even pay for its day to day operating and resupply costs, let alone its construction?
All proposals for large-scale space projects that are supposed to be profitable assume that there's a very large market for space-based facilities (large enough to make the amortized cost of the construction and upkeep lower than the cost of providing the needed services from the ground).
Given that industry has no pressing need to send anything more than a few satellites into space, where's the demand? You're not going to get enough tourists to pay for a $10 trillion "real" station.
In order to have a really useful space station, something that doesn't have an insanely high operating cost, it must be large.
Anything smaller than a million tonnes won't be self-sufficient. Any large station we'd build any time soon would be *more* expensive than a small station.
NASA, stop throwing away booster tanks; Take them to the ISS and duct tape them together if you have to. They're useful.
They also have mass, which means significantly less payload if you spend the extra effort to lift them to orbit instead of letting them drop. Some of the effort's already been spent by jettison time, but not all of it by a long shot.
In summary, lifting the tanks isn't free. You might as well lift something more useful instead.
First of all, it doesn't have to be completely self-sufficient, it only has to be more self-sufficient. Anything it can do to reduce the amount of mass you have to lift is good.
Second; industry. We should be (for example) actually building things in space instead of lifting them. Satellites are the prime example, since a fair number of them are launched now. Building them in orbit obviously saves money, all you have to do is maneuver them into position. You seem to assume that industry would not put up more satellites if the cost decreased; I disagree.
Also...
It's not free but you've already paid a considerable amount to take it most of the way. It wouldn't cost that much more to lift it the rest of the way, and mass in orbit is expensive. Again, even if all you used it for was to hold shielding, it would be worth it.
It is not cost-effective to build large structures in space (including the ISS) without actually doing the mining in space. We should be taking up only things which cannot reasonably be built in orbit.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
First of all, it doesn't have to be completely self-sufficient, it only has to be more self-sufficient. Anything it can do to reduce the amount of mass you have to lift is good.
This does not "make the space program profitable". This doesn't even make the space station you propose to build profitable. Cut supply costs by some small amount on a station that costs twice as much to build, or by a factor of two on a station that costs a hundred times as much? Either way, you're still paying *more*.
Second; industry. We should be (for example) actually building things in space instead of lifting them. Satellites are the prime example, since a fair number of them are launched now. Building them in orbit obviously saves money, all you have to do is maneuver them into position. You seem to assume that industry would not put up more satellites if the cost decreased; I disagree.
A satellite is a complex, specialized piece of equipment. It draws on a truly vast and diverse set of industries to build. You can't put all of those into space without needing a million tonne station, and putting only some of them into space gains nothing - you still have to supply most of your material from earth.
Secondly, if anything, industry demand for satellites has _decreased_. All of the constellation projects from the 1990s flopped spectacularly from the twin onslaught of cellular service proliferation (providing voice and data connections to most of the moving-user market) and improvements in fiber technology (we have network of fiber with a ludicrously high bandwidth linking all continents; the limiting factor is the routing electronics, not the linkages). There is no economic reason to route communications through satellites for anything but niche markets. The money is in ground-based communication.
The other main satellite use is remote sensing. I'd argue that the market for this is saturated already.
What satellites would companies put _up_?
It is not cost-effective to build large structures in space (including the ISS) without actually doing the mining in space. We should be taking up only things which cannot reasonably be built in orbit.
You are overlooking the cost of building the mining and manufacturing facilities needed to supply space construction. These are _huge_. Unless you _know_ you'll be building million tonne space stations, a mining facility costs more than just lifting materials from Earth.
You are also still assuming that an economic reason for large space construction exists at all. There is no industrial process for which there is significant demand that can be done in space that cannot be done more cheaply on earth (if you disagree - find one). There is no other profitable venture that anyone's been able to think of and make a good business case for that requires large-scale orbital construction. Vague noise has been made about ultra-pure crystals, exotic alloys, and so forth, but nobody's been able to produce a business case for these. Towing in an asteroid sounds like a great idea, but would only be useful if you needed the material in orbit - which we don't, at the moment. Selling to earth would be unlikely to be profitable vs. terrestrial mining operations, when you factor in the costs of towing the asteroid back.
To clarify once again - I love the idea of space exploration, and I hope we keep doing it. I just have no illusions about it being profitable any time in the near or medium-term future.
"Incidentally, there might be less confusion if you call them 'Europans' rather than 'Europeans'. There are about half a billion Europeans already, and we don't live anywhere near Jupiter."
I don't know about that. Given the state of European politics, you're definitely not from this planet.
God invented whiskey so the Irish would not rule the world.
I mostly agree, but there are plenty of things that humans can do that it's not practical or efficient for robots to do. Humans don't need a 20-minute (or longer) timelag to make the simplest decisions, are much better able to adapt tools in novel ways, and so should be able to get a hell of a lot more work done in certain sorts of investigation than robotic systems can. For that reason, I think manned Mars missions, provided they can be done at non-suicidal risk and affordable cost, are justifiable.
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
How come I can't get Celestia to show the correct phase and ring shadow at the same time, to look the same as this photo?
And: How phreaking kewl is it that we can view recent probe photos and have FREE (as in beer) software to simulate those photos? Wow.
M@
Krispy Cream is people
Speaking as a native american, I would have to concur. :-)