42
votes
Accepted
Can a spaceship land on an icy body using retropropulsion? wouldn't the ice melt?
Sorry for the length of this, but it brings up some interesting facts and possibilities.
The moons you mention, Titan, Europa, and Enceladus, are three very different places. Titan has a relatively ...
- 18.4k
34
votes
Accepted
Why are we interested in visiting the giant planets' icy moons?
The icy moons are of interest for exploration as part of the overall "follow the water" strategy of exploration that NASA (and others) have been exploring for some time. The "where else can water be ...
- 2,506
32
votes
Why aren't there any robotic missions on Europa or Enceladus?
There are probably many answers, but for guesstimating hypothetical missions a look at delta-V/subway maps like this are highly informative in terms of problem scale.
Working from that getting into ...
- 25k
23
votes
Accepted
Why aren't there any robotic missions on Europa or Enceladus?
@GremlinWrangler's answer sums up several important points;
Getting a low mass rover from Earth all the way to landing on the surface of one of those Moons requires much much more rocketry (delta-v) ...
- 151k
19
votes
Accepted
What would ice-skating be like on Europa?
Why Is Ice Slippery? That's a surprisingly involved question.
The main takeaways:
The common explanations of "pressure melting" and "frictional heating" are indeed true to some degree, but they can't ...
19
votes
Can a spaceship land on an icy body using retropropulsion? wouldn't the ice melt?
It's probably going to be less of a concern than you'd guess. The icy worlds of our solar system have essentially no atmosphere, so the surface materials will sublimate directly to vapor and be ...
- 172k
18
votes
Accepted
How unreachable are Jupiter's moons from Mars with the technology developed for going to Mars?
Let's go back our old friend the Pork chop plotter. Earth to Jupiter using minimum fuel takes around 2 years and you get one opportunity per year, more or less, to get there. You can shorten the ...
- 19.7k
16
votes
Why are we interested in visiting the giant planets' icy moons?
The motivation is the growing understanding, from the Voyager, Galileo and Cassini probes, that these icy moons (I'd throw in Enceladus) are geologically active with sub-surface oceans of liquid water,...
- 1,273
12
votes
How unreachable are Jupiter's moons from Mars with the technology developed for going to Mars?
I whomped up a spreadsheet to compare scenarios like this: Hohmann.xls.
Typing Earth into departure planet cell and Mars into destination planet I get
Launch windows open each 2.14 years (synodic ...
- 15.9k
11
votes
Would it be possible to send a nuclear bomb to Europa and make a hole in the ice of more than 11 km?
You may not send a nuclear bomb into space if you're one of the 105 countries that have signed the Outer Space Treaty that, among other things, forbids
deploying nuclear weapons or any other kinds ...
- 12.3k
11
votes
Is the far side of the tidally locked Europa moon safe from Jupiter's radiation?
The radiation that causes problems near Jupiter is not emitted by Jupiter. Jupiter has radiation belts, like Earth's Van Allen belts, but much more intense. This radiation doesn't consist of photons, ...
- 11.6k
8
votes
Why aren't there any robotic missions on Europa or Enceladus?
The motive for the exploration of Enceladus and Europa is different from that of Mars. The primary motive for exploration of the two moons is the possibility of finding an independent instance of ...
- 2,621
6
votes
What would ice-skating be like on Europa?
To complement:
There is the highest resolution photo of Europa surface by Galileo probe. Resolution is 6 meter per pixel.
We can see the surface is no so flat, more suited for alpine skiing than ice ...
- 9,121
6
votes
How to waterproof a rover?
Adapting an existing rover design to work underwater would be extremely cost prohibitive and it would be cheaper, more effective, and all around a better idea to design a whole new rover with ...
- 21.7k
6
votes
Accepted
Have the Europa Clipper's flybys and gravity assists of Jupiter's moons been pre-planned in detail?
Yes, there are detailed plans. Maybe not the final version, details can change. On Preliminary Design Review (PDR) in 2019 the tour version 17F12 was chosen as reference.
The details of this tour can ...
- 9,121
5
votes
Accepted
How does not orbiting Europa maximize Clippers coverage of Europa for a given radiation dose?
It seems to be a duty cycle thing:
Because Europa lies well within the harsh radiation fields surrounding
Jupiter, even a radiation-hardened spacecraft in near orbit would be
functional for ...
- 12.9k
4
votes
Would it be possible to send a nuclear bomb to Europa and make a hole in the ice of more than 11 km?
You'd have to bring a pretty large bomb to do this. We've detonated lots of bombs on Earth, and none of them came close to making a hole 11 km deep. We even did tests specifically aimed at making ...
- 131k
4
votes
A certain way to blow up Europa, what is wrong with this suggestion?
No. The water and ice are almost certainly under hydrostatic equilibrium. The ice is floating on the water. If you cut a hole in the ice, the water would fill the hole only part way, just like ice ...
- 151k
4
votes
What is the minimum pressure of a purely CO₂ atmosphere on Europa that can retain enough heat for surface liquid water?
A very rough starting point is how much this atmosphere would differ from a perfect blackbody.
The melting point of water is roughly 270 kelvin for a wide range of pressures, so with that as a surface ...
4
votes
Accepted
Could a planet only support underwater life?
Earth appears to support underwater life, cut off from the solar energy that powers the photosynthetic cycle we use. Powered by chemical reactions between hot water and minerals at subterranean ...
- 8,693
3
votes
How much will Europa Clipper weigh?
An estimate from 2016 has the mass budget at 5000 kg.
Curt Niebur, outer planets program scientist at NASA Headquarters, said at the meeting that the biggest challenge of adding the lander to the ...
- 131k
3
votes
Which side of Europa is which?
I find the accepted answer unclear, so I'll try:
The two maps in discussion use coordinate systems based on the convention that 0 longitude is the point directly facing Jupiter, but they have chosen ...
- 1,405
3
votes
Does Juno's UVS have any chance to spot Europa plumes?
There is a chance, if Juno can get close enough. According to the Planetary Society a distance of 40,000 km or less is needed to detect the plumes with the UVS. Other instruments can detect the ...
- 8,693
3
votes
A certain way to blow up Europa, what is wrong with this suggestion?
It won't be cataclysmic. Europa's ocean already vents to space, a probe would just add a small channel to that.
A narrow channel several km long will also clog up quickly because the liquid water ...
- 131k
3
votes
How unreachable are Jupiter's moons from Mars with the technology developed for going to Mars?
Using @HopDavid's excellent spreadsheet, we get a delta-V of about 6.9 km/s for a 3 year mission from highly elliptical Mars orbit to Callisto, the only one of the large moons where the radiation ...
- 19.7k
3
votes
Accepted
Is the available imagery of Europa and Enceladus enough to develop surface missions there?
Do the current (or soon to be obtained) surface maps of those bodies have a spatial resolution that is high enough to enable the development of lander & robotic missions to those destinations?
...
- 77.4k
3
votes
Why aren't there any robotic missions on Europa or Enceladus?
This is a late answer, but ...
Budget wise I believe the missions would cost the same as that of Mars.
You have grossly underestimated the cost of a Europa lander. The increased delta V needed to ...
- 77.4k
3
votes
Accepted
Why does Scott Manley say "the gravity of Europa is low enough that it's at the high end of what is possible in scuba with highly technical gear"?
Using saturation diving it is possible to go much deeper than possible with technical scuba diving.
For saturation diving a diving bell is needed to transport the diver from surface to the ground. ...
- 49.5k
2
votes
Would it be possible to use a electrodynamic tether or similar device on or within Europa to generate electricity from Jupiter's magnetosphere?
You need a current flowing through a conductor loop to generate electric power. A single long conductor does not suffice, a closed loop is needed.
Electrodynamic tethers in Earth orbit use the space ...
- 49.5k
2
votes
Comparison of Titan to Europa
Following is a block quote from How to Get an Atmosphere
by Peter Tyson
Saturn's moon Titan belongs to a very select club within the solar
system. It is one of only four "terrestrial" planets or ...
- 13.3k
Only top scored, non community-wiki answers of a minimum length are eligible