Author Topic: Proposed Europa Missions  (Read 323051 times)

Offline Blackstar

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Re: Proposed Europa Missions
« Reply #1520 on: 03/21/2017 02:29 AM »
A good argument could be made for delaying the lander until surface conditions are understood.  Having the lander die by being impaled on ice spikes during terminal descent would be double-plus ungood. But if delaying the lander, hopefully there'd be funding for instrument development and landing strategy studies, so some some of that risk can be bought down in the early, less expensive stages of such an ambitious project.

I think there are a lot of hidden risks that are not readily apparent--and by "risk" I don't mean simply "the spacecraft crashes" but more like "the spacecraft fails to perform the mission." What I've heard is that some of the instruments might be pretty difficult to design to return the data that you really want. So as you note, it might make sense to delay this stuff a bit to build better instruments.

Also, reread my previous post.

Offline as58

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Re: Proposed Europa Missions
« Reply #1521 on: 03/29/2017 11:06 PM »
Jeff Foust's tweets (https://twitter.com/jeff_foust) about Barry Goldstein's talk at National Academies Space Science Week contain some new info:

some picks:

- earliest launch window for Clipper is June 2022
- lander launch NET late 2025
- lander mission total mass 16 metric tons (Clipper is 6 tons). There are also pictures; the lander itself is a lot bigger than I had thought
- lander uses thermite-based incinerator for planetary protection at the end of the mission

Offline Blackstar

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Re: Proposed Europa Missions
« Reply #1522 on: 03/30/2017 02:13 AM »

Offline Archibald

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Re: Proposed Europa Missions
« Reply #1523 on: 03/30/2017 06:08 AM »
Quote
- lander mission total mass 16 metric tons (Clipper is 6 tons). There are also pictures; the lander itself is a lot bigger than I had thought

Well, that's the mass of a Lunar Module. Then again, landing on Europa probably takes a helluva lots of propellants.

Offline Zed_Noir

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Re: Proposed Europa Missions
« Reply #1524 on: 03/30/2017 07:06 PM »
Quote
- lander mission total mass 16 metric tons (Clipper is 6 tons). There are also pictures; the lander itself is a lot bigger than I had thought

Well, that's the mass of a Lunar Module. Then again, landing on Europa probably takes a helluva lots of propellants.

What are they proposing for lander propulsion?

Offline Blackstar

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Offline Archibald

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Re: Proposed Europa Missions
« Reply #1526 on: 04/04/2017 06:41 PM »
Must be hypergolic.

Offline AegeanBlue

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Re: Proposed Europa Missions
« Reply #1527 on: 04/04/2017 11:26 PM »
One question I am having about Europa Clipper: As far I know the heaviest mission launched to date (or I should say that made it to the launchpad) is Mars 96, which is still slightly heavier than Cassini. Would Europa Clipper break that record and become the heaviest planetary probe ever?

Offline redliox

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Re: Proposed Europa Missions
« Reply #1528 on: 04/05/2017 12:24 AM »
Must be hypergolic.

Pretty much everything sent beyond the Moon's orbit operates with hypergolic because it's easy to store and well understood.  I'm almost tempted to wonder how well SEP would function at braking into Jupiter's orbit although I suspect 'not well' as a default answer due to weak sunlight and power-hungry systems.
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Offline plutogno

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Re: Proposed Europa Missions
« Reply #1529 on: 04/05/2017 06:46 PM »
One question I am having about Europa Clipper: As far I know the heaviest mission launched to date (or I should say that made it to the launchpad) is Mars 96, which is still slightly heavier than Cassini.

Fobos Grunt was reported at 13,535 kg at launch, as it had to carry the engine for escaping Earth and for orbit insertion, Chinese probe and adapter. hard to beat that

Offline AegeanBlue

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Re: Proposed Europa Missions
« Reply #1530 on: 04/06/2017 06:25 PM »
One question I am having about Europa Clipper: As far I know the heaviest mission launched to date (or I should say that made it to the launchpad) is Mars 96, which is still slightly heavier than Cassini.

Fobos Grunt was reported at 13,535 kg at launch, as it had to carry the engine for escaping Earth and for orbit insertion, Chinese probe and adapter. hard to beat that

Apparently the Europa Lander in its current iteration would. Let's see if it does go forward, I would prefer a Uranus or Neptune orbiter to the current iteration of Europa Lander.

Offline shooter6947

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Re: Proposed Europa Missions
« Reply #1531 on: 04/06/2017 06:41 PM »
I'm almost tempted to wonder how well SEP would function at braking into Jupiter's orbit although I suspect 'not well' as a default answer due to weak sunlight and power-hungry systems.

Badly.  (1) not enough sunlight to generate power, as you mention; (2) thrust too low, which means; (3) no Oberth effect advantage.

Online ChrisGebhardt

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Re: Proposed Europa Missions
« Reply #1532 on: 04/10/2017 05:52 PM »
NASA to Reveal New Discoveries in News Conference on Oceans Beyond Earth

NASA will discuss new results about ocean worlds in our solar system from the agency’s Cassini spacecraft and the Hubble Space Telescope during a news briefing 2 p.m. EDT on Thursday, April 13. The event, to be held at the James Webb Auditorium at NASA Headquarters in Washington, will include remote participation from experts across the country.

The briefing will be broadcast live on NASA Television and the agency's website.

These new discoveries will help inform future ocean world exploration -- including NASA’s upcoming Europa Clipper mission planned for launch in the 2020s -- and the broader search for life beyond Earth.

The news briefing participants will be:
Thomas Zurbuchen, associate administrator, Science Mission Directorate at NASA Headquarters in Washington
Jim Green, director, Planetary Science Division at NASA Headquarters

Mary Voytek, astrobiology senior scientist at NASA Headquarters

Linda Spilker, Cassini project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, California
Hunter Waite, Cassini Ion and Neutral Mass Spectrometer team lead at the Southwest Research Institute (SwRI) in San Antonio

Chris Glein, Cassini INMS team associate at SwRI
William Sparks, astronomer with the Space Telescope Science Institute in Baltimore
A question-and-answer session will take place during the event with reporters on site and by phone. Members of the public also can ask questions during the briefing using #AskNASA.

To participate by phone, reporters must contact Dwayne Brown at 202-358-1726 or dwayne.c.brown@nasa.gov and provide their media affiliation no later than noon April 13.

Offline Star One

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Proposed Europa Missions
« Reply #1533 on: 04/13/2017 06:51 AM »
Quote
NASA Watch‏ @NASAWatch

Watch @NewsHour tonight for a story on #Europa and #NASA space policy with @milesobrien @Alienoceans
@CongCulberson & Robert Walker

https://mobile.twitter.com/NASAWatch/status/852281281392107520
« Last Edit: 04/13/2017 06:52 AM by Star One »

Offline Star One

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Proposed Europa Missions
« Reply #1534 on: 04/13/2017 06:28 PM »
Cross posting from the Cassini thread as more evidence of Europa plumes.

NASA press release 

https://www.nasa.gov/press-release/nasa-missions-provide-new-insights-into-ocean-worlds-in-our-solar-system
« Last Edit: 04/13/2017 06:29 PM by Star One »

Offline Alpha_Centauri

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Offline Alpha_Centauri

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Re: Proposed Europa Missions
« Reply #1536 on: 04/13/2017 07:14 PM »
Interesting post on Mike Brown's blog regarding verifying if the proposed hotspot is real, looks like it might be;

http://www.mikebrownsplanets.com/2017/04/europa-is-hot.html
« Last Edit: 04/13/2017 07:19 PM by Alpha_Centauri »

Offline Star One

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Proposed Europa Missions
« Reply #1537 on: 04/13/2017 07:23 PM »
Interesting post on Mike Brown's blog regarding verifying if the proposed hotspot is real, looks like it might be;

http://www.mikebrownsplanets.com/2017/04/europa-is-hot.html

So is that where the lander mission should go, dependent on further data from Europa Clipper?

Seems about the right time to post this with narration written and spoken by Carl Sagan.

« Last Edit: 04/13/2017 07:44 PM by Star One »

Offline Alpha_Centauri

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Re: Proposed Europa Missions
« Reply #1538 on: 04/13/2017 07:53 PM »
I'd imagine the lander would land in the safest place possible, the Europan surface can be very rough.

Offline Star One

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Re: Proposed Europa Missions
« Reply #1539 on: 04/13/2017 07:56 PM »
I'd imagine the lander would land in the safest place possible, the Europan surface can be very rough.

I am sure I read today that once the lander has finished its mission it will incinerate itself?