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NASA's Cassini Spacecraft Begins Its Final Mission Before Plunging Into Saturn (popsci.com)
NASA has announced that their Cassini spacecraft will begin its final mission before slamming into Saturn on April 23rd. The "final mission" consists of a series of dives through a 1,500-mile-wide gap between Saturn and its rings. "No spacecraft has ever gone through the unique region that we'll attempt to boldly cross 22 times," said Thomas Zurbuchen, associate administrator for the Science Mission Directorate at NASA Headquarters in Washington. "What we learn from Cassini's daring final orbits will further our understanding of how giant planets, and planetary systems everywhere, form and evolve. This is truly discovery in action to the very end." The spacecraft will then dive into the gas giant's atmosphere, where it will "break apart, melt, vaporize, and become a part of the very planet it left Earth 20 years ago to explore," Cassini project manager Earl Maize said. Popular Science explains in its report why Cassini has to die: Some space probes are allowed to keep orbiting their targets in perpetuity after their mission ends -- like the Dawn spacecraft at the dwarf planet Ceres. But things are a lot more complicated around Saturn. Whereas Ceres is essentially just a really big rock with no moons, Saturn has 62 satellites, at last count. The gravitational push and pull from those moons -- especially the largest, Titan -- wreak havoc on Cassini's trajectory, which it normally corrects by burning fuel. But the spacecraft's fuel is running out, and ultimately its fate is sealed by its own discoveries; scientists don't want to risk the spacecraft crashing into Titan and Enceladus, which may be capable of supporting life. Although Cassini launched 20 years ago, experiments on the Space Station have suggested microbes can survive for years in the extreme temperatures, radiation, and airless vacuum of space. If NASA were to accidentally put water bears on Enceladus, the tiny Earthlings could potentially wipe out any native lifeforms that the moon may harbor, and/or complicate the search for those alien organisms later. This is why Cassini must die now, while NASA can still control its last swan dive.
Prime Directive and all....
Life with a potentially separate origin to life on earth is of interest to science. Therefore you don't destroy it. The idea is that you don't destroy something you want to study, because once it is destroyed you won't be able to study it.
I hope that breaks it down for you.
I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.
They're anthropomorphising the plucky little space probe. Let them have their fun.
I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.
So, let's deliberately put water bears on Saturn to limit the risk to Titan and Enceladus? How can they be so sure that there isn't a layer of Saturn with composition, pressure, and temperature favorable to life?
Aside from it being a gas giant, Saturn's huge gravity well will pull Cassini in hard and fast, vaporizing every little bit of it back into elements and simple compounds (like oxides of the metals). No bugs can survive this plunge.
...but would it not also have been an option to slingshot Cassini out of the local system of Saturn altogether? (say, via a close fly-by of Titan, or something) To set it on some really long-shot trajectory across the solar system, from which it could conceivably be collected in a few decades once we get the hang of proper space propulsion?
That way, a truly historic artefact could have been preserved, without risking contamination of Saturn's moons?
Oh, maybe remotely piloting a very expensive probe, with hours long time lag, in orbit around a very cluttered planet and very complex math and projections to assist with what needs to be where.
Imarine playing a driving sim, where you had to plan the entire race from before it started and had no real time control to move away from something coming at you and 0 options of a do over
So, plenty to be daring about.
"It means," said Marvin, "that the ship is going to dive into Saturn. Saturn... Dive. It's very simple to understand. What do you expect if you steal Hotblack Desiato's stunt ship?"
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
If Cassini smashes into Saturn and later probes find water bears on Enceladus, then that will be historic news
Why? Because they were smart enough to use the escape pods? Or that NASA built water bear escape pods into Cassini in the first place?
I'd say that's a non-issue. At worst you moderately irradiate one small area. More likely the fuel vaporizes during reentry or impact, and gets diffused enough that the radiation and potential toxicity doesn't even register as noise against the background levels.
Life is a problem because it's self-replicating. Let just one microbe manage to survive, and with a few years and good luck it could colonize the entire planet, destroying any realistic chance we have of locating native life, and possibly even wiping it out.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
"While we feared a resumption of direct attacks since the missile strike least year (their code name for the mission was "Schiaparelli"), the 3rd planet merely continues their siege of Mother Mars: their land-attack rovers plowing implacably above our heads on the Martian surface, continue to drill/probe to find an entrance to our homes. Their reconnaissance orbiters taking constant pictures forcing our defense forces to remain camouflaged. All Martian citizens are ordered to remain on alert! Do not go outside! Do not approach these murderous killing machines!
However, Martian Military Intelligence has also reported a pending assault on our peace-loving allies of the Ringed Planet. The Water Planet has sent a massive Death-Star which has heretofore patrolled above the Skies of Saturn, seeking any opportunity to slaughter any innocent transport vehicle it would come across, compelling a complete cessation of Qrgrzantik shipments and triggering the Qrgrzantik shortage which we continue to suffer. New information gained by our brave operatives in place on the 3rd planet suggests that in frustration at their inability to engage the Saturnian Space Navy, this death-ship (code name: Cassini) is now intending a suicidal death strike into the Saturnian home-cloud. This is the exact sort of attack such frustrated barbarians would finally attempt.
We offer our brethren-in-arms in Saturn our hopes and prayers that all will be safe.
We now return you to regularly scheduled programming.
MSN out."
-Styopa
Daring: adventurous or audaciously bold // adventurous courage
Adventurous: willing to take risks or to try out new methods, ideas, or experiences.
Bold: showing an ability to take risks; confident and courageous.
So..... flying a very expensive craft, billions of miles away, on hours long time lag, with limited fuel, in a crowded orbit that no human eye has ever seen directly, some how isn't bold or daring?
Yeah. Sure thing. :/