Cassini's Saturn Mission Goes Out In A Blaze Of Glory (npr.org) 74
An anonymous reader shares a report: Controllers at NASA's Jet Propulsion Laboratory sent a final command Friday morning to the Cassini spacecraft orbiting Saturn. Not long after, accounting for the vast distance the message traveled, the order was received, putting the craft into a suicidal swan dive, plummeting into the ringed planet's atmosphere. Flight Director Julie Webster called "loss of signal" at about 7:55 a.m. ET, followed by Project Manager Earl Maize announcing "end of mission" as the spacecraft began to break up in Saturn's atmosphere. "Congratulations to you all," Maize announced to applause. "It's been an incredible mission, incredible spacecraft, and you're all an incredible team." With Cassini running on empty and no gas station for about a billion miles, NASA decided to go out Thelma & Louise-style. But rather than careen into a canyon, the plucky probe took a final plunge into the object of its obsession. Just how obsessed? Its 13-year mission to explore the strange world of Saturn went on nearly a decade longer than planned. It completed 293 orbits of the planet, snapped 400,000 photos, collected 600 gigabytes of data, discovered at least seven new moons, descending into the famed rings and sent its Huygens lander to a successful 2005 touchdown on the surface of yet another moon, Titan. Also read: Cassini's Best Discoveries of Saturn and Its Moons.
RIP (Score:5, Insightful)
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Re: RIP (Score:2)
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Maybe not everything in this world always has to be about "Jobs". Maybe you could learn to live a little.
Re: RIP (Score:1)
Ever been unemployed? Underemployed? It ain't easy.
It's all about the jobs unless one is filthy rich and able to spend time and money doing worthwhile things that may or may not pay the rent and food.
So yes, hurrah for all the science! things Cassini did, but also be cognizant of all the roofs it put over people's heads and how many mouths it fed, directly and indirectly.
We need another impossible dream like apollo. Maybe direct similar energies and funds to cancer research.
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Yeah, I've been both. And you know what, I didn't spend my time looking for someone/something else to blame for my woes. I didn't become a bitter boy. That said, it's a total mind f*ck. But, I didn't lash out at to make myself feel better.
Of course, I hold myself personally responsible for my actions and plan accordingly.
You?
Re: RIP (Score:4, Informative)
Here you go: http://www.21stcentech.com/money-spent-nasa-not-waste/
And this: https://www.sciencefriday.com/articles/meet-the-researchers-behind-the-cassini-mission/
And from here: http://www.airspacemag.com/flight-today/team-cassini-180960062/
"one of more than 5,000 people who have worked on the project over the years"
Maybe next time do research on your own and get educated about the subject before you bitch about it.
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NASA has been a source for fundamental technology [wikipedia.org] development for its entire existence. These technologies support industries that provide millions of jobs to Americans who work is every sector including medicine, information technology, communication and transportation.
If you are trying to challenge the ideas of technology development and exploration, then kindly find yourself a nice tree to live in and a puddle of mud to drink, because that is were humans would be right now if regressive ideas like yours
Re: RIP (Score:1)
About $3.2 billion dollars worth over 30 years. So a little more than $100 million per year, on average. That's about the cost of one bombing mission to syria, which managed to destroy one airbase, per year.
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You religious/luddite communists, and the things you think government should be doing, are hilarious.
I realize that you had a stunning victory in the 2016 presidential election, comrade, and that's something we can't ignore. But do you really think America will roll over and play dead? We're totally going to bury you. By 2024 election everyone is going to realize that whatever commie runs on "jobs" is the guy that everyone needs to vote against. You're not going to kill technological/economic progress, you
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...Go.
4chan.luser
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Rather than pile on from that ivory tower, how about you tell me how many fucking US jobs this created. How many families were fed, how much production to the GDP was done, how any of this shit made any real sense at all other than to a few propeller heads. Go.
I found a 2010 picture of the Cassini team [nasa.gov] and it looks like it created about 100 primary jobs related to the mission itself, I saw a later photo and there were a lot more people in the team. So at least 100 families were fed from STEM roles in the US. How is that bad, for the US or any other country for that matter.
In terms of the GDP and propeller head it's much better that these skilled people were working for NASA and the product of their intellectual output can be utilized in the GDP, indirectly, in
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Ooooh, a troll. I wanna play...
Can you sat "Idiocracy"?
I knew you could.
And they say the movie industry doesn't reflect reality...
Cassini (Score:2)
Re:Cassini (Score:4, Funny)
And yet phones aren't expected to last past their year warranty. ;)
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It was launched in 1997!
And yet phones aren't expected to last past their year warranty. ;)
Well... if the phone cost as mush as the spacecraft, it probably would. I'm guessing that cost was in the $1.4b "pre-launch dev" part. From Cassini–Huygens [wikipedia.org]:
The total cost of this scientific exploration mission was about US$3.26 billion, including $1.4 billion for pre-launch development, $704 million for mission operations, $54 million for tracking and $422 million for the launch vehicle.
Re:Cassini (Score:5, Informative)
Re: Cassini (Score:5, Informative)
You have it backwards. The upper display was x band. It faded first because the antenna has higer gain at the higher x band frequency, so the pointing is more critical. S band was on the bottom and faded a bit later because the dish has a wider beamwidth at 2 GHz than it does at 11 GHz.
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Can anyone by chance find a Youtube vid of those band screens during the dive?
Did it boldy go too? (Score:2)
I saw what you did there.
Contamination (Score:4, Interesting)
TFA states that plowing the craft into Saturn was necessary to prevent contamination of the moons, but the mission began with dropping a Huygens Lander [wikipedia.org] on Titan.
Seems like nobody has make the distinction between bacterial contamination and radioactive contamination. I suspect that the latter is actually the concern as the probe used an RTG for power and thus it was safest to de-orbit it into Saturn.
RIP Cassini. Thanks for all the science.
Re: Contamination (Score:5, Informative)
It was a worry over biological contamination. JPL (and NASA) have very specific protocols for planetary protection. Huygens went through some extreme decontamination prior to launch. Cassini, as an orbiting probe, not so much. Also, at launch we didn't know as much about the Saturn system and it's moons. The RTGs aren't really a concern, as they're not all that radioactive. Pu-238 is primarily an alpha emitter, and is mostly just toxic.
Re: Contamination (Score:4, Informative)
It was a worry over biological contamination. JPL (and NASA) have very specific protocols for planetary protection. Huygens went through some extreme decontamination prior to launch. Cassini, as an orbiting probe, not so much. Also, at launch we didn't know as much about the Saturn system and it's moons.
Specifically, we learned that Enceladus has a large subsurface ocean, at the bottom of which may lie hydrothermal vents. Since those on Earth are often teeming with life, we didn't want to risk contamination of Enceladus' oceans.
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...
Specifically, we learned that Enceladus has a large subsurface ocean, at the bottom of which may lie hydrothermal vents. Since those on Earth are often teeming with life, we didn't want to risk contamination of Enceladus' oceans.
Really, they didn't want the Enceladusians to capture our technology.
Anything to delay the inevitable misunderstanding when they discover Mexican food.
Talk about hydrothermal vents!
Life needs water (our kind of life, anyway) (Score:5, Informative)
TFA states that plowing the craft into Saturn was necessary to prevent contamination of the moons, but the mission began with dropping a Huygens Lander [wikipedia.org] on Titan. Seems like nobody has make the distinction between bacterial contamination and radioactive contamination. I suspect that the latter is actually the concern as the probe used an RTG for power and thus it was safest to de-orbit it into Saturn.
It was a worry over biological contamination.
Exactly. Huygens was battery powered: after the battery died, it dropped to a temperature of about 90K, barely above liquid nitrogen. No terrestrial life will contaminate anything at that temperature.
Cassini, on the other hand, contained several RTGs. In the unlikely case that it did impace into Titan, the RTGs would keep a tiny fraction of the probe debris above the liquidus point of water, and hence in principle terrestrial contamination could survive and even multiply.
The scenario is absurdly unlikely, of course, but it can't be absolutely ruled out, and since it can't be ruled out, it triggers the planetary protection protocol.
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The scenario is absurdly unlikely, of course, but it can't be absolutely ruled out, and since it can't be ruled out, it triggers the planetary protection protocol.
Yet it doesn't stop us from dropping dozens of probes and landers onto Mars and Venus...
Nor did it stop the even more microscopic risk of contaminating life on Saturn itself - slingshoting Cassini at the sun or outer space would have been even "safer".
I have a suspicion that the real goal was to go out in a spectacular "suicide", in order to create publicity. Nothing wrong with that, but be open about it.
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I think you missed the word "slingshot".
The point is using the orbital movement and gravitational pull of Saturn and its larger moons to increase the speed with every passing until escape velocity has been achieved. You need very little fuel for such an operation, and we have used it many times in the past, including with Cassini itself, as it got gravity assist from Venus twice, then Earth, and then Jupiter. And it's how it has navigated through the Saturn system with extremely little fuel used.
Departure
You don't "spiral" into the sun. (Score:3)
Yep. They could either have sent it out of the solar system (when it had enough juice left) or spiraling into the Sun. Didn't necessarily have to crash land on a planet.
You don't "spiral" into the sun. You watch too much star trek. Orbits are not spirals.*
Dropping into the sun would have required escaping Saturn's gravity well-- which Cassini didn't have the fuel to do-- and then cancelling out Saturn's orbital angular momentum around the sun, which requires 9.6 km/sec, well beyond anything remotely possible with Cassini even if it had full fuel tanks on its main braking engine.
Going "out of the solar system" would require "merely" 4 km/sec after escaping Saturn's grav
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Dropping into the sun would have required escaping Saturn's gravity well-- which Cassini didn't have the fuel to do--
Actually escaping Saturn's orbit and going into solar orbit was one of the possible end-of-mission scenarios. When they were looking at the options, it would only have required 5-35m/s of delta-v, well within Cassini's capabilities. However, having a planetary probe in heliocentric orbit doesn't get you much science, as its instruments aren't designed for that kind of thing. At most they would have had a semi-long term observation of the solar wind, which can be done with missions that are much easier to ma
Re:Life needs water (our kind of life, anyway) (Score:4, Funny)
Yet it doesn't stop us from dropping dozens of probes and landers onto Mars and Venus...
All of which followed pretty strict decontamination procedures. Well, maybe not the Venus probes, but if Earth bacteria manages to survive on Venus, I say more power to them.
Re:Life needs water (our kind of life, anyway) (Score:5, Informative)
The scenario is absurdly unlikely, of course, but it can't be absolutely ruled out, and since it can't be ruled out, it triggers the planetary protection protocol.
Yet it doesn't stop us from dropping dozens of probes and landers onto Mars and Venus...
Mars probes are sterilized and follow a rigorous planetary protection protocol. This has a large and annoying effect on the Mars program: we're not allowed to land on the spots on Mars that have even a slight likelihood of having life or an environment where any possible form of Earth life could survive.
Venus probes-- well, the surface of Venus is hostile to any possibly terrestrial forms of life, and while the upper atmosphere could possibly harbor extreme acidophiles, not anything that's likely to contaminate a probe. In any case, though, the missions to Venus went there before planetary protection protocols were put in place.
Nor did it stop the even more microscopic risk of contaminating life on Saturn itself
Cassini hit the Saturn atmosphere at a velocity of 34 km/sec-- 76,000 mph. No microscopic life is going to survive.
Think of it as hitting with the energy of a 1/3 kiloton bomb.[ref [arxiv.org]]
- slingshoting Cassini at the sun or outer space would have been even "safer".
"Safer" but utterly impossible. The reason the mission was over was it was pretty much out of fuel.
I have a suspicion that the real goal was to go out in a spectacular "suicide", in order to create publicity. Nothing wrong with that, but be open about it.
Uh, no.
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Yet it doesn't stop us from dropping dozens of probes and landers onto Mars and Venus...
As I mentioned above, there is an entire policy (and in fact a portion of the organization) dedicated to planetary protection. Surface landers, such as what are sent to Mars (and in the future Europa and/or Enceladus) are required to go through very strict decontamination regimens before they are launched. In addition to being assembled in clean rooms (as are all the probes), they are baked/irradiated/cleaned with caustic chemicals/etc... prior to launch to sterilize them as much as possible. They don't wan
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I have a suspicion that the real goal was to go out in a spectacular "suicide", in order to create publicity. Nothing wrong with that, but be open about it.
I don't think the goal was publicity, but I'm sure they don't mind the publicity either. If you read the article at the end it mentions there was science to be done that could only be obtained [hopefully] by a suicidal plunge through the atmosphere. Previously the probe could never get close enough to Saturn to record its exact magnetic tilt or directly analyze the atmosphere, both of which they are hoping to get readings of from Cassini's final descent. With the limited fuel remaining the suicide run was p
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Slingshot it using what?
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Not necessarily. Spores could survive in a frozen state, and then later if a liquid water volcano or similar erupts, the spores could awake and seep toward the core. Unlikely and/or many years away, but not impossible.
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While it's possible there is life on Titan, it seems improbable; considering the extremely low temperatures. Titan has some of the conditions for life, but a lot of available free energy isn't one of them.
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While it's possible there is life on Titan, it seems improbable; considering the extremely low temperatures. Titan has some of the conditions for life, but a lot of available free energy isn't one of them.
Titan almost certainly has a subsurface ocean, which could have hydrothermal energy, which on Earth life can use as an energy source. We don't know of exchange between the subsurface ocean and the surface, but there might be exchange of material. Therefore, even though it's unlikely, we don't want to contaminate the surface.
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Seems like nobody has make the distinction between bacterial contamination and radioactive contamination. I suspect that the latter is actually the concern as the probe used an RTG for power and thus it was safest to de-orbit it into Saturn.
I'm pretty sure that because the Huygens lander [wikipedia.org] was designed to land on the surface that NASA already made the distinction decades ago. Landing on the surface might introduce bacterial contamination and that's why most spacecraft are assembled in clean rooms.
Farewell Cassini (Score:2)
Farewell Cassini. You were an explorer, a pioneer, a scientist, a teacher, but most importantly, you were an inspiration to us all. You may be gone, but the legacy you left and the knowledge you taught us will outlive us all. Goodbye old friend, you will be missed.
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Indeed. Cassini is another great triumph of space exploration, and shows we can build some pretty damned hardy and long-lasting probes.
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Nothing on netcraft. Shenanigans!
Super advanced civilization (Score:1)