Author Topic: Why are there no missions planned to Enceladus? (Read 46211 times)

Blackstar · « **Reply #40 on:** 06/24/2016 08:17 pm »

Yep. And of course a key question in all of this is what do you want to do with the spacecraft? And that's related to the power issue and all the rest. While you can put a brick in orbit there and power it with big solar panels, that doesn't do anything. It is possible that one of your science requirements might be for a certain amount of power for a certain amount of time, coupled with high pointing accuracy--and solar panels might allow for two of those things, but not all three. That's a long-winded way of saying that it all depends.

I sat through a recent explanation about the trades for Europa Clipper and they were fascinating. Some interesting stuff about how the Europa orbiter approach required near continuous communications back to Earth and that drove the power requirements rather high. But the flyby approach enabled them to operate instruments at one point, then do the communication back later at a lower data rate and that lowered the power requirements a lot and enabled solar. There were other aspects to it as well, but once you hear about all these trades you realize that designing a spacecraft is a lot like trying to squish a balloon and if you push on one side it bulges out on the others, so you have to address multiple issues simultaneously.

Alpha_Centauri · « **Reply #41 on:** 06/30/2016 09:23 pm »

Just a heads-up as not a lot of information yet, but as I heard previously it looks like there will be an Enceladus (and Titan) mission proposed for ESA's M5 (and appears to anticipate significant US involvement);

https://e2tmission.wordpress.com/

Two mass specs. for Enceladus plume and Titan atmosphere and a thermal imager to map the tiger stripes and get higher resolution images (50-100m) of Titan.

Essentially it is in the same vein as ELF and JET, in fact it looks like one of the spectrometers is from ELF and the thermal imager is from JET.

No clue whether it will get very far in the selection, but one to watch.

leovinus · « **Reply #42 on:** 09/30/2020 06:53 pm »

Not sure whether this is the best thread but I thought that Enceladus mission proposal deserves a mention
Enceladus Orbilander: A Predecadal Mission Concept Study
https://www.lpi.usra.edu/opag/meetings/opag2020fall/presentations/MacKenzie_6019.pdf

leovinus · « **Reply #43 on:** 10/25/2020 03:36 pm »

Quote from: leovinus on 09/30/2020 06:53 pm

Not sure whether this is the best thread but I thought that Enceladus mission proposal deserves a mention
Enceladus Orbilander: A Predecadal Mission Concept Study
https://www.lpi.usra.edu/opag/meetings/opag2020fall/presentations/MacKenzie_6019.pdf

And a nice write-up at planetary.org Meet Orbilander, a Mission to Search for Life on Enceladus. In the context of "What is life?", I like the broad detection approach which will be relevant for other missions as well.

Quote

No Single Life Detection Instrument

Orbilander would rely on a complex suite of instruments to determine whether Enceladus’ water has a blend of chemicals conducive for life as we know it, and search for amino acids, lipids, and cells. The instruments include mass spectrometers to weigh and analyze molecules, a seismometer, a microscope, and a DNA sequencer.

leovinus · « **Reply #44 on:** 12/19/2020 05:37 pm »

Quote from: Blackstar on 06/24/2016 08:17 pm

Yep. And of course a key question in all of this is what do you want to do with the spacecraft? And that's related to the power issue and all the rest. While you can put a brick in orbit there and power it with big solar panels, that doesn't do anything. It is possible that one of your science requirements might be for a certain amount of power for a certain amount of time, coupled with high pointing accuracy--and solar panels might allow for two of those things, but not all three. That's a long-winded way of saying that it all depends.

I sat through a recent explanation about the trades for Europa Clipper and they were fascinating. Some interesting stuff about how the Europa orbiter approach required near continuous communications back to Earth and that drove the power requirements rather high. But the flyby approach enabled them to operate instruments at one point, then do the communication back later at a lower data rate and that lowered the power requirements a lot and enabled solar. There were other aspects to it as well, but once you hear about all these trades you realize that designing a spacecraft is a lot like trying to squish a balloon and if you push on one side it bulges out on the others, so you have to address multiple issues simultaneously.

More on Enceladus Life Finder (ELF) and its solar power ideas. https://twitter.com/ltelkins/status/1339950883178643457

leovinus · « **Reply #45 on:** 12/31/2020 07:35 pm »

Quote from: leovinus on 10/25/2020 03:36 pm

Quote from: leovinus on 09/30/2020 06:53 pm
Not sure whether this is the best thread but I thought that Enceladus mission proposal deserves a mention
Enceladus Orbilander: A Predecadal Mission Concept Study
https://www.lpi.usra.edu/opag/meetings/opag2020fall/presentations/MacKenzie_6019.pdf

And a nice write-up at planetary.org Meet Orbilander, a Mission to Search for Life on Enceladus. In the context of "What is life?", I like the broad detection approach which will be relevant for other missions as well.

Quote
No Single Life Detection Instrument

Orbilander would rely on a complex suite of instruments to determine whether Enceladus’ water has a blend of chemicals conducive for life as we know it, and search for amino acids, lipids, and cells. The instruments include mass spectrometers to weigh and analyze molecules, a seismometer, a microscope, and a DNA sequencer.

And the full NASA concept study at https://science.nasa.gov/files/science-red/s3fs-public/atoms/files/Enceladus%20Orbilander.pdf
and attached as well.

leovinus · « **Reply #46 on:** 01/25/2021 06:46 pm »

Quote from: leovinus on 12/19/2020 05:37 pm

Quote from: Blackstar on 06/24/2016 08:17 pm
Yep. And of course a key question in all of this is what do you want to do with the spacecraft? And that's related to the power issue and all the rest. While you can put a brick in orbit there and power it with big solar panels, that doesn't do anything. It is possible that one of your science requirements might be for a certain amount of power for a certain amount of time, coupled with high pointing accuracy--and solar panels might allow for two of those things, but not all three. That's a long-winded way of saying that it all depends.

I sat through a recent explanation about the trades for Europa Clipper and they were fascinating. Some interesting stuff about how the Europa orbiter approach required near continuous communications back to Earth and that drove the power requirements rather high. But the flyby approach enabled them to operate instruments at one point, then do the communication back later at a lower data rate and that lowered the power requirements a lot and enabled solar. There were other aspects to it as well, but once you hear about all these trades you realize that designing a spacecraft is a lot like trying to squish a balloon and if you push on one side it bulges out on the others, so you have to address multiple issues simultaneously.

More on Enceladus Life Finder (ELF) and its solar power ideas. https://twitter.com/ltelkins/status/1339950883178643457

A copy of the slides used at the presentation of Enceladus Life Finder (ELF) to PSDS: Ocean worlds and Small Dwarfs, Meeting #14. ELF is an older proposal but I understand this is useful to informative the ongoing discussion.

I liked the mass spectrometry discussion on p3/4, the observation of H2 abundance, and no consumption of it. On p7, I liked the discussion of distinguishing CO and N2 via spectrometry. While Cassini's spectrometry could not resolve them, the spectrometry on Europa Clipper (MASPEX) would be able to do it. Finally, the discussion of a "speed limit" of spectrometry on p9 was new to me. Thank you. The background article Program options to explore ocean worlds was mentioned in the summary.

vjkane · « **Reply #47 on:** 07/24/2021 02:27 pm »

There's a good open access new paper in The Planetary Science Journal on the science case for returning to Enceladus:

https://iopscience.iop.org/article/10.3847/PSJ/abfb7a

Blackstar · « **Reply #48 on:** 07/24/2021 06:53 pm »

Quote from: vjkane on 07/24/2021 02:27 pm

There's a good open access new paper in The Planetary Science Journal on the science case for returning to Enceladus:

https://iopscience.iop.org/article/10.3847/PSJ/abfb7a

Here is the pdf:

Blackstar · « **Reply #49 on:** 03/25/2024 04:21 pm »

https://www.esa.int/Science_Exploration/Space_Science/Saturn_s_moon_Enceladus_top_target_for_ESA

vjkane · « **Reply #50 on:** 03/25/2024 06:28 pm »

Quote from: Blackstar on 03/25/2024 04:21 pm

https://www.esa.int/Science_Exploration/Space_Science/Saturn_s_moon_Enceladus_top_target_for_ESA

Well, this will mess up NASA's thinking about New Frontiers topics, which currently is considering Enceladus.

I haven't read the document, but some thoughts:

ESA tends to follow through on their long range plans, so this is likely. On the other hand, there are many steps between this and a formally approved mission

This is a decision to target a specific destination (with studies of a number of other moons, too). It's not a specific mission proposal. Flybys only? Orbit Enceladus? Land on Enceladus? All to be determined.

I haven't looked for a target date in the document, but I expect the late 2040s or even the 2050s arrival in the Saturn system. And while ESA tends to follow through on their strategic plan (I believe there are fewer cancellations than in NASA's program of specific missions), ESA does have many schedule slips. (Based on my age, I don't expect to be around. Bummer. You young wiper snappers, enjoy!)