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Cassini's “Grand Finale” Will Be a Blaze of Glory (scientificamerican.com)
140 points by okket 9 months ago | hide | past | web | favorite | 51 comments

I've read a few accounts of this mission's end and, not to be dramatic, but I have actually been moved to tears by the thought of this probe using its last energy to point it's antenna toward earth as it melts in the atmosphere. Yes, it's just some hardware but it feels so poetic to me. This sort of accomplishment gives me hope in our species--a true triumph of science that I feel fortunate to have witnessed.

Also, for anyone who hasn't seen it, Cassini's Twitter feed has had a ton of great content over the pat few years (@CassiniSaturn).

Not unlike the Terminator being lowered into a vat of molten steel and using his last moment to make a thumbs up.

The NYtimes has a remarkable page of images taken by Cassini (moons and saturn). Space being stark and empty is strangely movingly beautiful sometimes.


The writing of the narration was really excellent: "Some of Cassini's orbits took it behind Saturn, an alien sunset before hours of darkness".

The six sided hexagon hurricane on the top of Saturn was the most fascinating to me, especially when they superimposed the size of earth over it saying it could "swallow 4 earths"...

It's weird, isn't it? I had the same feeling listening to the announcer on NPR mention it this morning. It's like, "here's this one last useful thing I can do before I go to certain death."

Wont happen so dramatically. By the time anything is melting the aero forces will have far exceeded the probe's ability to point. It will start with a very slow tumble, breaking contact. The spinning and destructive heating will come some minutes (hours?) later. Of course, due to distance, by the time we see the break in contact the probe will be gone, allowing the op's careful language re timings to make it seem like everything will happen at once.

i bet you're fun at parties.

I still think someone within this community could make this into a dramatic short film.

The problem is the only thing we have capable of witnessing this event is the thing experiencing it.

If this moves you, you will certainly enjoy the documentary "The Farthest" about the Voyager missions. You can stream it on PBS.

It is very bittersweet, the near future does not look promising for multi function probes like Cassini. NASA looks to be sending less "risky" probes from here on out. Cassini was a huge engineering success given the possible outcomes.

Agreed about the hope for our species.

As a species and as individuals we're capable of such astounding accomplishments like this; yet also capable of outstandingly in(s)ane idiocy.

How can society be arranged/evolved to encourage the former, and limit the latter? Is such a thing possible? Desirable?

The lack of societal optimization, or even moving towards the optimal, frustrates me!

"If you chase away my demons, my angels might leave, too."

I still think the key is raising the collective intelligence. Not that smart people are always productive, but they are capable of being so.

So long as the average human is just barely sapient, we aren't going to be collectively achieving much. It's always exceptional individuals who have great achievements.

Average people don't really do much. Nothing personal against being average, of course, it's just not sufficient for great achievement.

I think intelligence augmentation, such as neural lace and Neuralink, is a step in the right direction.

That final paragraph about the members of the Cassini team having watching their kids grow and have children of their own during the 30 years of the mission kind of struck me. I wonder what things are like for them when their mission comes to such a sudden end?

I suspect they'll have to spend some time analyzing the data, possibly months (I'm not really sure how long), but then it's over. What do they do? Take a long vacation and then pick up another project at NASA? Or have they been working on multiple projects this whole time, and it will be more like a developer shipping a new feature, you celebrate for a few minutes then move on to the next priority?

They will be working on designing, simulating, and building new missions to the outer planets. It's really important to have a roadmap for long-term exploration rather than doing one-shot missions, so you don't lose the expertise. The National Academy of Science works on this roadmap, and NASA generally follows it (see http://sites.nationalacademies.org/SSB/SSB_052297, in particular the Planetary Science survey from 2011).

It's a very exciting time for planetary science, especially regarding the "Ocean Worlds" (those moons of Jupiter, Saturn, and Neptune that have liquid water: https://www.jpl.nasa.gov/infographics/infographic.view.php?i...).

One of particular interest is Europa Clipper (https://www.jpl.nasa.gov/missions/europa-clipper/), although Europa is a moon of Jupiter.

I don't know what shape the team's careers will take, but this is anything but sudden for them. Planning for this started about a decade ago.

I remember years ago reading about all the options they were considering, including some really ambitious ones, like moving it to another gas giant over the course of decades. But costs would be high, failure a real possibility, and fuel very low. So we got the amazing last few months of images and science. And now comes the fiery end, with some final data and no chance to accidentally crash on Enceladus or Titan.

I was in 7th grade when Cassini launched, and I remember thinking, "Wow, cool! That seems really interesting!". And then, "Holy Cow, 7 years before it gets there?!".

And then I remember in 2004 hearing about its arrival, and remembering back to 7 years prior and getting excited again about learning new things about these faraway places.

Finally, in 2017, I'm excited about what new information might be obtained during the short dive into the atmosphere. It's been a good run!

I know this meanders into off-topic, but I remember when we first put humans on the moon. To have lived through all of these changes, and advances, has been wonderful.

Me too! In 5th grade our teacher had a sister who worked at NASA and she was able to give our class nice laminated artwork showing what it may look like on Titan. They also got everyone's signature which was supposed to be digitized and put on a disc on Cassini (they said they were going to get 1 million signatures or something). Ever since then I have always been excited to watch anything regarding Cassini. I was sort of sad when I heard they were going to crash it into Saturn. What a way to go though!


Despite all the negative news lately. . . Well constantly, I have to admit, things like this give me hope.

I do hope it inspires the next generation (at least a couple), to see what we did, realise where we have gone wrong, and push for more exploration.

This is quite a tangent, but figured I'd mention to anyone who might be interested that there's a pretty cool podcast recently from Radiolab about the life and times of the Voyagers. It goes into some interesting details about their exit from the solar system. http://www.radiolab.org/story/sun-dont-shine/


NASA's countdown with distance and updates

For us on the hither side of the pond, "7:55 eastern time" means 13:55 Stockholm time. Since the US is so vast in all directions, "your" time references always confuse me.

0 days, 21 hours, 42 minutes, and 10 seconds. That's when the world will end (for Cassini).

It's not that different from Europe. You have Western, Central, Eastern Europe times plus Moscow Time. We have Pacific, Mountain, Central, and Eastern. Forgot Alaska time zone.

Belarus and Turkey don't change for daylight savings and neither does Arizona here.

Yeah except most of Europe is in the Central time zone: https://en.wikipedia.org/wiki/Time_in_Europe. Sometimes I encounter GMT/BST times but only when looking at UK things. It's all CET/CEST here.

You also forgot Hawaii and possibly Guam -- I can never remember how their time lines up.

The US has four "contiguous US" timezones, and two or three others for peripheral things. Not counting stuff like Zulu or the various zones that dont adjust for DST, so technically are distinct.

Hawaii (UTC-10) and Guam (UTC+10) are separated by the international date line.

Alaska, Guam, and Hawaii usually don't come up in my consersations. Don't the Dutch/UK and other countries still own some islands?

You are correct. I was speaking only to continental Euro/US.

I see articles about Cassini's end, but they never clearly mention when the final pictures will be revealed. Any pointers please?

This timeline has an entry for when the final pictures are expected to appear online:


Thanks for the link, great overview. I think this ominous line rings particularly dark and gruesome, "Cassini reconfigures from an orbiter to an atmospheric probe".

It can't take pictures in Jupiter's atmosphere?

The spacecraft is at Saturn. During its final time, it will not have the transmission speed to send pictures, though it will send atmospheric measurements until the very end.

It could, but the Deep Space Network is the bottleneck 100kbit speeds and hours round trip makes getting the data difficult in best conditions, eg. orbiting out by titan

A pretty good summary video of Cassini's mission. https://www.nytimes.com/2017/09/08/science/cassini-saturn-na...

For another take on this, check out this funny twitter thread: https://twitter.com/Alex_Parker/status/907803594463891458

off-topic, but UTF-8 still isn't ready for prime time on this site obviously: "crême brûlée" became "crme brle" :)

Would rather they have it go through the rings and get some point blank photos of the contents, if that's a possibility.

I remeber them doing this with Galileo flown in to jupiter. Mixed sadness and pure impressiveness. However there was some talk that it might have caused a nuclear explosion on Jupiter as Galileo had 2 two radioisotope thermoelectric generators. This explision then could have started a chain reaction as jupiters contains high amounts of tritium and deuterium.

This would make for a fun scifi plot, from the perspective of Jupiter natives. "These assholes from Earth dropped a nuke from orbit. They appear to be preparing to do the same to our cousins on Saturn. What do we do now?"

I was picturing a large number of classic flying saucers with domed tops rising en masse from the surrounding clouds, pointing themselves towards earth, and speeding away. I mean, we did just drop a bus on them.

Nuked from orbit. It's the only way to be sure.

> However there was some talk that it might have caused a nuclear explosion on Jupiter as Galileo had 2 two radioisotope thermoelectric generators. This explision then could have started a chain reaction as jupiters contains high amounts of tritium and deuterium.

This is just about as likely as CERN generating a Earth-eating black hole. RTGs can't generate a nuclear explosion.

"there was some talk"

There's always daft chatter, make sure that tinfoil is properly adjusted. Dirty engineering and physics nixing the silliness twice over in this case.

"The Lucifer Project"


Do you know the difference between even and odd isotopes?

NASA released a fantastic dramatic video explaining the Cassini mission and final stages, very inspirational to watch.

The Grand Finale: https://www.youtube.com/watch?v=xrGAQCq9BMU

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