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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
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??
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
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'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!!
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.
RTG (radioisotope thermal generators) are very safe. A rocket that carried one blew up in the 60's. The RTG survived perfectly intact. They are even built better today. You have got to understand that these things are strong. They are designed to withstand reentry, an exploding rocket, and crashing into the ground
If you don't understand any of my sayings, come to me in private and I shall take you in my German mouth.
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.
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.
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.
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."