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Liquid water 'lake' revealed on Mars

bbc.co.uk

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Re: Liquid water 'lake' revealed on Mars

#21

Post by elorant »

liberte82 wrote: post #11

Why don't we send a rover to some of these interesting places? It seems like we're constantly making fascinating finds on Mars, then send rovers to the middle of a random rocky desert.

Because it takes ages to plan a new mission and the vehicle we send is related to the goals of each mission. It's not like they have a rover stand-by and then decide where to land it. The equipment of the vehicle and the research it has to carry very much determine the way it will be build. So what we've send so far depends on the data we had years ago.

Re: Liquid water 'lake' revealed on Mars

#22

Post by ryanmercer »

brlewis wrote: post #7

For those, like me, wondering how this is even possible: In order to remain liquid in such cold conditions (the research team estimate between -10 and -30 Celsius where it meets the ice above), the water likely has a great many salts dissolved in it.

It is also quite possible Mars still has 'hot spots' as geologically it was very 'recently' volcanically active. Every now and then there's little anomalies that possibly hint at subsurface hot spots that might allow for hot springs and similar.

In Robert Zubrin's fictional (but hard-science) book "First Landing" on the first manned Mars mission they actually find a hot spot and drill into it resulting in a geyser (which obviously, the water instantly freezes creating a snow-like effect). All of Zubrin's books are worth reading if you are at all interested in manned missions to Mars. He has some non-fiction looks (that are a bit outdated now due to scientific discoveries, like finding the polar caps are lousy with water ice) but he goes into the math and gets you in the right mindset. The fiction book is similar in nature to The Martian (came out well before The Martian) and he also has a short little fiction book meant to be sold to future colonists called 'How to Live on Mars: A Trusty Guidebook to Surviving and Thriving on the Red Planet' which also takes a hard-science fiction approach to the subject.

Re: Liquid water 'lake' revealed on Mars

#24

Post by mattlondon »

liberte82 wrote: post #11

Why don't we send a rover to some of these interesting places? It seems like we're constantly making fascinating finds on Mars, then send rovers to the middle of a random rocky desert.

From the BBC article it suggested that getting a rover there might be difficult.

Since they were talking about flying rovers, I would assume this means that it is not a nice flat plain like the current wheeled-rovers are used to driving around on. I am guessing that it means that it probably looks a lot like this: https://en.wikipedia.org/wiki/Brei%C3%B0amerkurj%C3%B6kull#/...

Kinda fascinating though. I would assume that instead of drilling they could just use some sort of heated "drill" that just sinks through the ice slowly but surely. Probably less to go wrong mechanically?

Re: Liquid water 'lake' revealed on Mars

#25

Post by hoorayimhelping »

liberte82 wrote: post #11

Why don't we send a rover to some of these interesting places? It seems like we're constantly making fascinating finds on Mars, then send rovers to the middle of a random rocky desert.

A couple of reasons. The first is that to make a mission to Mars cost effective, we have to wait about 18 months for Earth and Mars to line up in the right positions, otherwise it costs too much in rocket fuel to be worthwhile. The second is that the missions lag behind the discoveries - it's much easier to analyze pictures and spectographs than it is to design a mission, secure funding for it, and then do it. Sending a landing craft to Mars is not very easy. We've done it successfully a few times, but we've failed quite a few times as well. A lot of these discoveries happen in places that it isn't trivial to land a rover. We put them in flat deserts because it's safer to and there is still much to learn there, but liquid water doesn't necessarily get found in places rovers can go. I imagine we're much more cautious with rovers on Mars than we are on say the moon. It's very costly to make a mistake and lose a rover on Mars.

Re: Liquid water 'lake' revealed on Mars

#26

Post by actsasbuffoon »

mFixman wrote: post #23

20 years ago it would have been unthinkable to find water in any other planet in the solar system. Mark my words: in 20 years, we'll find extremely simple proto-bacterial life in Mars and in many other planets.

Or even on moons. There are several moons that have a non-zero chance of having life on them.

Re: Liquid water 'lake' revealed on Mars

#27

Post by simias »

hossbeast wrote: post #20
brlewis wrote: post #7

For those, like me, wondering how this is even possible: In order to remain liquid in such cold conditions (the research team estimate between -10 and -30 Celsius where it meets the ice above), the water likely has a great many salts dissolved in it.

It seems like, being under ground, it would also be subject a higher than normal pressure, which would also help

I was wondering about that, how deep is it exactly? If TFA mentions it I missed it. Given the planet's low gravity and very thin atmosphere I presume it must be pretty deep in order to remain liquid.

They mention Lake Vostok at the end of the article which is 4km deep but it's probably not directly comparable.

Re: Liquid water 'lake' revealed on Mars

#28

Post by 52-6F-62 »

walrus01 wrote: post #15
liberte82 wrote: post #11

Why don't we send a rover to some of these interesting places? It seems like we're constantly making fascinating finds on Mars, then send rovers to the middle of a random rocky desert.

Building a rover that can drill more than a few inches deep is presently a huge technical challenge. If you look at drill rigs used by humans for water wells and such, the rover will need to be 8x larger and heavier than the current Curiosity.

See: Armageddon, the movie.

Maybe we just need to go full Bruce Willis. Somebody get Ben Affleck to sing Leaving on a Jet Plane.

In seriousness, it sounds like a fascinating problem. If anyone has seen the drills they use to make holes for piles for new condo/office towers—they're probably wider than needed in this case (not actually sure of that)— the drill (bit?) is extendable, but the rig itself is enormous. Those are mobile units.

Otherwise something like a semi-permanent or permanent unfolding oil-rig type machine would be needed?

None of this helps with the weight problem. I wonder if there's a more clever option.

Re: Liquid water 'lake' revealed on Mars

#29

Post by throwaway5752 »

elorant wrote: post #21
liberte82 wrote: post #11

Why don't we send a rover to some of these interesting places? It seems like we're constantly making fascinating finds on Mars, then send rovers to the middle of a random rocky desert.

Because it takes ages to plan a new mission and the vehicle we send is related to the goals of each mission. It's not like they have a rover stand-by and then decide where to land it. The equipment of the vehicle and the research it has to carry very much determine the way it will be build. So what we've send so far depends on the data we had years ago.

https://en.wikipedia.org/wiki/Mars_Science_Laboratory#Histor...

Curiosity landed 8 years after the call for proposal. If I recall, the landing site (Gale Crater rim) was considered extremely interesting at the time.

Re: Liquid water 'lake' revealed on Mars

#30

Post by rm_-rf_slash »

liberte82 wrote: post #11

Why don't we send a rover to some of these interesting places? It seems like we're constantly making fascinating finds on Mars, then send rovers to the middle of a random rocky desert.

I wonder if it might make sense to have a kind of satellite around Mars with a series of probes that can be deployed wherever interesting things are suggested to be but aren’t necessarily expected to be mobile, beyond perhaps drilling downwards.

That way as more interesting discoveries are made via rovers or other technologies, we can deploy a probe right away instead of having to plan and build and hurl a rover through space for a year and a half.

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