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Suddenly, It Seems, Water Is Everywhere in Solar System

nytimes.com

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Re: Suddenly, It Seems, Water Is Everywhere in Solar System

#81

Post by mitchty »

rquantz wrote: post #70
rquantz wrote: post #37

Earlier quoted context omitted.

And yet, the US will never convert to a system of measurement invented by the French . Remember freedom fries?

I'm not allowed to edit this anymore, so let me reply instead. To those downvoting I ask: do you think this comment wasn't serious? You think there aren't at least 47 senators who would filibuster a bill to, say, convert the US highway signs to metric because it's "unamerican"?

Well to be sure we were going down that route. Then Reagan got elected. Take that what you will.

Re: Suddenly, It Seems, Water Is Everywhere in Solar System

#82

Post by kchangnyt »

Shivetya wrote: post #5
bladedtoys wrote: post #4

Has anyone thought much about an (admittedly near impossible) probe to burrow and submarine around in the oceans of some of the juicier Galilean and Saturnian moons?

I thought NASA was already planning for such to go to Europa

Yes, NASA is working on Europa Clipper: http://www.jpl.nasa.gov/missions/europa-clipper/ But that would just make multiple flybys of Europa, not land or tunnel into the water.

Re: Suddenly, It Seems, Water Is Everywhere in Solar System

#83

Post by noselasd »

acomjean wrote: post #57
ohitsdom wrote: post #50

Earlier quoted context omitted.

How would you get data back? I'd imagine you'd have to have a surface relay, to a moon-orbiting satellite, then back to earth.

They come to the surface, then get a gps fix (err) and then is picked up by the boat then the data uploaded..... Ok its going to need some minor modifications.

You also need to get from the surface to the water, and from the water back to the surface. Inbetween is a rather huge layer of ice. On Europa it's though to be 10-20 kilometers thick, though there's indications it could be as "thin" as 3km some places

Re: Suddenly, It Seems, Water Is Everywhere in Solar System

#84

Post by myblake »

moreproductive wrote: post #78
vortico wrote: post #74

Everywhere except California apparantly. https://news.ycombinator.com/item?id=9198260

I came here to post this exact post. Bravo. And sad face (I live in LA)

Heh also came to say the same thing. On reddit it would have obviously happened asap but I thought maybe there's less snarky humor on HN. Guess we couldn't resist this one though.

Re: Suddenly, It Seems, Water Is Everywhere in Solar System

#85

Post by warkdarrior »

TorKlingberg wrote: post #66
aguywithamum wrote: post #42

Earlier quoted context omitted.

Yeah, that's in reference to the failure of Beagle 2. It's on the page that was linked by Someone1234 ( https://en.wikipedia.org/wiki/Mars_Climate_Orbiter#Cause_of_... ).

The Beagle 2 and Mars Climate Orbiter are not the same thing. It is unknown why Beagle 2 failed and there is no reason to believe it was due to any unit mismatch. It may be that two of the solar panels failed to deploy.

It's well known that the metric solar panels failed to deploy. The imperial solar panels opened successfully, but that did not generate enough electricity to keep going.

Re: Suddenly, It Seems, Water Is Everywhere in Solar System

#86

Post by xpinguin »

V-2 wrote: post #6
bladedtoys wrote: post #4

Has anyone thought much about an (admittedly near impossible) probe to burrow and submarine around in the oceans of some of the juicier Galilean and Saturnian moons?

For what it's worth, there's quite a decent s-f movie "Europa Report" about a manned mission to the Jupiter's moon. It avoids most genre cliches, apart from the very ending maybe.

>It avoids most genre cliches, apart from the very ending maybe.

Yeah, by being fully made of those. [SPOILER ALERT]

* lack of crew psychological cross-matching

* some ludicrously exoggerated hydrazine drama

* chloroplast-equipped organisms in the environment which ambient light spectrum is slightly inclined towards gamma radiation (not to mention the meat-packed space vessel itself, brightly shined up by very same light)

* _one_ central computer with sole purpose to be heroically repaired on the _outer_ shell of the vessel (you see, no EVA - no drama)

* (mentioned ending) transferring at least tens of gigabytes from Europe to Earth in a matter of seconds (via that special hero-driven central computer) despite being unable to establish uplink for past several months already due to the broken trasmitter (of course, unreserved)

---

Well, I understand that this is just a movie, but look, why not to put it in agreement with some common sense?

Re: Suddenly, It Seems, Water Is Everywhere in Solar System

#87

Post by buss »

pwnna wrote: post #73
throwaway_yy2Di wrote: post #71

Earlier quoted context omitted.

In practice, the ΔV differences are actually way smaller than that chart suggests. Those figures are for direct transfers (per the legend). But if you allow indirect trajectories with gravity assists [0], that makes things drastically cheaper. To intercept Jupiter, you can steal much of the needed ΔV from flybys of the inner planets (at the tradeoff of time , waiting to go around the sun multiple times). And maneuver…

Keep in mind, for a human mission, you want to minimize time, rather than deltaV. Gravity assists will take a lot of time, as you spend a lot of time waiting for the encounter. Furthermore, that chart is likely computed via a direct Hohmann transfer, which is one of the most efficient transfer maneuvers available. It also will take a lot longer. For practical human travel to destinations farther way, you need to perf…

> Keep in mind, for a human mission, you want to minimize time, rather than deltaV. Gravity assists will take a lot of time, as you spend a lot of time waiting for the encounter.

True, but we could throw the big ship with all the supplies into a flight path that gains a lot of momentum around the inner planets and intercept it with a much smaller craft only loaded with enough fuel to get the astronauts to the transit ship (and back, if necessary).

Re: Suddenly, It Seems, Water Is Everywhere in Solar System

#89

Post by anigbrowl »

finnh wrote: post #77
coderzach wrote: post #30

Earlier quoted context omitted.

> However I'd laugh at anyone who suggest metric is better because people inherently internalise it better I disagree. Once you've been taught a base ten counting system, units that change based on orders of magnitude is very easy to understand. Since almost everyone has a base ten counting system internalized, metric is MUCH easier.

But 12 is evenly divisible in thirds and quarters. Actually pretty useful for a bunch of things. Really it's just too bad we have 10 fingers instead of 12.

Yep, but 10 fingers is what most of us have. I like 12 too but unless you can persuade people to start counting in astrological symbols instead of decimal digits then metric is the way to go.

Re: Suddenly, It Seems, Water Is Everywhere in Solar System

#90

Post by jperras »

ohitsdom wrote: post #47
Mahn wrote: post #28

Does anyone else think NASA should reconsider their plans for a manned mission to Mars? With Europe, Ceres, Enceladus, Ganymede and many more promising moons out there it seems kind of a waste to spend time, effort and capital in Mars now.

Jupiter's moons are exciting, but have huge radiation concerns. Still trying to solve that for the flight to Mars.

Ganymede is the exception here, due to the fact that it is the only Jovian moon with it's own magnetosphere.
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