The thread for space cadets!

[Samson]

Liquid water found on Mars!!!!!

An international team of researchers claim to have found a lake of liquid water beneath an ice cap on Mars.

The lake, which is circular and only about 20 kilometres wide, is the first time that liquid water has been found on the planet, and comes on top of evidence that Mars may have hosted seas and rivers in the past. The lake is about 1.6 kilometres below the surface and at least 900 centimetres deep - any less and it would not have been picked up.

However, with a temperature estimated at between -10 and -30 degrees Celsius, the assumption is that the water has an exceptionally high salt content and probably doesn't currently support life of any form.

"It's plausible that the water may be an extremely cold, concentrated brine, which would be pretty challenging for life," Dr Claire Cousins, an astrobiologist from the University of St Andrews, told the BBC.​

I would take issue with "probably doesn't currently support life of any form". There is not enough evidence of this, and even on earth archaea can survive in many extreme environments including high salt.

 

[hobbsyoyo]

I would take issue with the finding itself until it's been confirmed by other spacecraft. Even then, I'm going to be suspicious until someone actually drills into it and proves it due to all the issues with orbital data. There are other explanations for this and in the past we've seen alternative explanations win out over the flashy headlines.


There is also a small part of me that doesn't want this to be true because if it is then that will be the end of the NASA/ESA rover expeditions after the current batch launches. Why? Because as you point out, if this is real then it is almost certainly habitable. Mars already has the highest classification for planetary protection (from contamination) which puts a yuuuge regulatory burden on launches to the red planet. Basically they have to spend a ton of money decontaminating everything that launches to the red planet to make sure we don't accidentally contaminate the planet with Earth life. Not only is this decontamination costly, it is also risky for the vehicles themselves as it is a stressful procedure for hardware to go through.

If there is liquid water, there is almost surely life. And if that's the case then planetary protection regulations are about to grow substantially to the point where I don't think NASA/ESA will risk future exploration after the current batch launches. I could even see NASA's planetary protection officer plotting to thwart the currently planned rovers by throwing a bunch of new regulations at them.

 

[red_elk]

You don't want extraterrestrial life to be discovered because it will complicate decontamination procedures for future Mars probes?

 

[hobbsyoyo]

You don't want extraterrestrial life to be discovered because it will complicate decontamination procedures for future Mars probes?

If that was it, I'd be fine with it. I'm afraid however that the reaction will be quite a bit more dramatic and will ultimately result in all-out bans on future missions. They won't call it a ban; they'll just put the burden on future missions so high no one can achieve them. Plus, it will give government the excuse to clamp down on private exploration of the red planet. I do want to move to Mars eventually and that won't be possible if they find proof of life there before people actually show up and begin looking in earnest.

 

[Berzerker]

https://phys.org/news/2018-07-reveal-diamond-cache-deep-earth.html

Cratons - ancient relatively stable cores upon which the continents formed - are rich(er) in diamonds far beyond what researchers believed.

Now I find this interesting, diamonds can be formed when asteroids hit the Earth. Maybe these diamond rich cratons resulted from large impactors. A 200 mile wide asteroid slams into the Earth and up springs a craton loaded with diamonds floating around on a denser mantle. And the shape of these cratons also suggests that scenario, they look like inverted mountains, like a snow cone. Thats the structure I'd expect from an impactor punching thru the crust.

 

[hobbsyoyo]

Northrup is offering to link all profits on their cost-plus contract for the James Webb Space Telescope (JWST) to the success of the mission. That's a baby step in the right direction but really it's a hollow gesture to drum up good will with congress. Because it is cost-plus, Northrup can never lose money on this, no matter what happens. They've already taken in billions of additional dollars and blown through multiple cost-caps on the program. The telescope could be cancelled today and they still made a ton of money and would break even at worst. No one has and no one will actually hold them responsible for their mismanagement. And of course NASA itself is also at least partially responsible for what a mess this program has become.

Overall I think we'll never see another mission like this one. We've reached the limits of what you can do with small(ish) diameter rockets and future mega projects like this should absolutely wait until huge rockets like the SLS, BFR or NG are flying regularly. Folding up a telescope was always going to be a risky business and I'm not sure this thing is even going to work correctly when it finally gets off the pad.
https://spacenews.com/northrop-ceo-offers-to-link-jwst-profit-to-mission-success/

 

[uppi]

Overall I think we'll never see another mission like this one. We've reached the limits of what you can do with small(ish) diameter rockets and future mega projects like this should absolutely wait until huge rockets like the SLS, BFR or NG are flying regularly. Folding up a telescope was always going to be a risky business and I'm not sure this thing is even going to work correctly when it finally gets off the pad.

As far as I know, the diameter of those "huge" rockets is in the 7-9m range. That would allow to transport a monolithic mirror of JWST size, but not a much bigger mirror. So in case the JWST works, you would still need to have some way to avoid a monolithic mirror for any potential successor telescope. If you don't manage to do that, you might as well give up on space-based optical astronomy for the next few decades.

 

[hobbsyoyo]

As far as I know, the diameter of those "huge" rockets is in the 7-9m range. That would allow to transport a monolithic mirror of JWST size, but not a much bigger mirror. So in case the JWST works, you would still need to have some way to avoid a monolithic mirror for any potential successor telescope. If you don't manage to do that, you might as well give up on space-based optical astronomy for the next few decades.

This is a fair point. However, the mirrors are not the only part of the telescope that have to fold. Even if these big rockets don't have big enough fairings to avoid all folding, if they can still cut out most of the folding it would still go a long way toward fixing these problems. To a large extent, almost all satellites have to fold away antennas and solar arrays. The problem here isn't necessarily the fact that anything has to fold but rather how much has to be folded. But yes, folding optics is probably a bad idea.

Also, these big rockets may start out with 7-9m fairings but fairings are one of the few parts of rockets that can rather easily be stretched and widened. Well not easily as nothing about space is easy but still it's easier to widen the fairing that the tanks and so on. And it's pretty common for fairings to grow. F9 did it (but only by a smidge), Atlas did it, Titan did it, Delta did it, Proton is going to do it, Soyuz did it ans so on. The difference here is that if you start with a 7-9m fairing and grow it by a few meters, that a much less massive change than stretching a baseline 3m fairing out to 12m.

 

[Broken_Erika]

I think the onion has the best take on this Martian lake.

World-Eating Leviathan Awoken From 500-Million-Year Slumber In Martian Underground Lake After Feeling Sonar Disturbance

 

[Colon]

I do want to move to Mars eventually and that won't be possible if they find proof of life there before people actually show up and begin looking in earnest.

There doesn't seem to be enough CO2 to terraform Mars though: https://www.space.com/41318-we-cant-terraform-mars.html

In light of that, it seems only fair Mars any measure is taken to avoid possible contamination. Colonizing Mars isn't going to do anything to ensure human survival at this point.

 

[hobbsyoyo]

Pronouncements like that should be taken with a massive grain of salt due to lack of evidence.

Why do think a martian colony would do nothing to ensure human survival in the long term?

 

[uppi]

Why do think a martian colony would do nothing to ensure human survival in the long term?

Any event that result in the extinction of humans on earth is likely to doom a Martian colony as well. The problem is that Mars is so hostile that you need to maintain an extremely complicated technology stack just to survive. As a result it is very difficult to achieve true self-sufficiency in the near future. You can probably get very close, but without the technology base on earth that can supply a spare part once in a while, it is very easy to end up in a situation where a technical failure dooms the colony, because there is not enough time to build up the technology stack that you need to make the necessary repairs.

 

[Cutlass]

Pronouncements like that should be taken with a massive grain of salt due to lack of evidence.

Why do think a martian colony would do nothing to ensure human survival in the long term?

Full self sufficiency over the long term is a very complicated project. Just recall the Biosphere 2 failure. And the fact that the experiment hasn't been repeated yet. We don't even yet know what we don't know in terms of making an indefinitely sustainable colony.

 

[hobbsyoyo]

Any event that result in the extinction of humans on earth is likely to doom a Martian colony as well. The problem is that Mars is so hostile that you need to maintain an extremely complicated technology stack just to survive. As a result it is very difficult to achieve true self-sufficiency in the near future. You can probably get very close, but without the technology base on earth that can supply a spare part once in a while, it is very easy to end up in a situation where a technical failure dooms the colony, because there is not enough time to build up the technology stack that you need to make the necessary repairs.

Full self sufficiency over the long term is a very complicated project. Just recall the Biosphere 2 failure. And the fact that the experiment hasn't been repeated yet. We don't even yet know what we don't know in terms of making an indefinitely sustainable colony.

Your time scales are too short. This is a multi-generational project. Yup, it won't bear fruit for centuries. That doesn't make it less worth the effort.


Also Biosphere shouldn't be used as a counter example for a lot of reasons. It failed because dumb people do dumb things. Let's not gamble the future of life in our universe on that example.

 

[r16]

what can destroy Earth can not destroy Mars by the year 2300 ? Or the entire Milky Way ?

 

[Colon]

Pronouncements like that should be taken with a massive grain of salt due to lack of evidence.

Why do think a martian colony would do nothing to ensure human survival in the long term?

What Uppi said basically. The fundamental problem is economies of scale. We take it for granted the affordability of something like iron ore is because of there are massive economies involved with it. Miners can cater to a market of +7 billion people and as result can operate with huge machinery, stripping entire mountains, going hundreds of meters deep and transporting the wares all over the planet on huge ships and trains that use infrastructure built for them. Companies and authorithies building the necessary equipment and facilities can in turn rely a market of hundreds of miners and transportation firms around the globe. All of that hugely drives down the per unit cost of providing iron ore (incidentally, this is also why free trade is so beneficial). There's nothing of that on Mars, so per unit costs for resources are going to be much, much higher. The same applies to manufactured goods and services. Even if markets often are a lot more fragmented in those, producers can still rely on much bigger markets and thus obtain much larger economies of scale, than would be the case in a Martian colony. As a result, Mars is going to be heavily dependent on Earth for a very, very long time.
Now maybe advances in robotics would make such a colony viable on its own in the distant future, but if that's going to be case, there's no reason we can't wait until then. Hence, the only reason we'd colonize Mars ASAP is to get a headstart on terraforming. However, if terraforming isn't possible to start with, I think it's only reasonable to hold off any colonizing until we've determined for certain there isn't native life. Mars is still going to be there a century from now.

 

[hobbsyoyo]

You haven't actually addressed what I said. Just because the pay off will be delayed doesn't justify delaying the start. You can say it's better to wait until technology matures and I say we should start now to force the technology to mature.

You're saying we'll figure out the tools we need to do this (robotics, whatever) eventually anyways. That implies that these tools are necessary for improving the lives of people on Earth, else why would they be developed? They would be just as useful now as they would be in the future - actually, quite a bit more useful now thanks to compounding returns.

Therefore we should absolutely short circuit that natural R&D cycle and get to work on projects that require these new tools. What's developed for the Mars effort will feedback into daily life here on Earth.

I think it's easy to show that if the governments of the world hadn't gone full-in on the space race in the 60's, the fruits of those efforts (GPS, better computers, better materials, etc) likely would have taken decades longer to be developed and integrated in today's economy. The faster we get to these live improving innovations, the better off all people all - least of which the people of the Earth. We cannot make a fully self-sufficient Martian colony now or likely for decades or centuries. But the effort that goes into making that happen will have immediate pay-off for the Earth.

Plus, your argument that we should wait because the effort will take centuries actually defeats itself. It may take us centuries to make a Martian colony and indeed if we wait a couple of centuries people will still be saying, 'well if we just waited a few more centuries the effort will go faster still' despite how much conditions have changed on the ground.

Extinction or other lesser but nonetheless horrific outcomes won't necessarily take decades to play out. There are not a lot of safeguards to prevent complete annihilation of the human race in just a few hours and what safeguards that do exist mostly rely on human intervention which shouldn't be counted on. Therefore we should start this effort now in hopes we can reach a state of self-sufficiency on Mars as soon as possible.

I cede that up until this decade, realistically a Martian effort would have been a costly, miserable failure. But technology has improved to the point that we're within striking distance and in my opinion we should go all in. In any case it's a much better use of tax dollars than building yet more fighter jets and ICBMs. (Don't know if you guys heard but both Russia and the US are developing new delivery systems with new warheads likely to follow shortly)

 

[hobbsyoyo]

The fact that we can send useful communications infrastructure to Mars that's the size of a shoebox for less than $100 m (including launch costs) should tell you something about the maturity of our space technology. Granted, the shoe box comm sats now on their way to the red planet are not as capable (by orders of magnitude) as a fiber optic installation but the costs are in fact comparable which is remarkable considering the previous state of affairs of space technology. It costs billions to send last-generation rovers to Mars and the moon. Now private companies are preparing to do with only millions in funding.

It is very easy to underestimate the pace of change in the industry right now. 'Revolution' is a word that gets thrown around about it and it's honestly completely a justified descriptor of what is happening. Launch costs are dropping off a cliff while new technologies are being put forward and successfully used on a yearly basis. At the same time the cost of those new technologies is similarly dropping off a cliff and because of all that there are now dozens of start ups in the rocket and spacecraft marketplace. It's to the point where the giants of the industry (Lockheed et al) are pouring funding into these start ups to profit themselves - which gives the start ups necessary capital to scale up. It's gangbusters right now. Really incredible stuff is happening.

Honestly if you had a magic wand and gave me the power to go back in time and work on any space project in history I would stay exactly where I am doing exactly what I'm doing. Apollo was flashy and awesome and outright impressive but it legitimately pales in comparison to what is happening right now. That sounds crazy, I know, but it's true. And Apollo really was the best thing ever in my opinion...

 

[red_elk]

This sounds like an interesting scenario for a sci-fi novel.
Barely self-sustainable Mars colony struggles to survive, while Earth civilization got destroyed (asteroid strike, nuclear winter, or something else).
People put their last resources to send expedition to Earth, to salvage materials impossible to obtain on Mars, may be rescue survivors...

I think maybe we should start with technically simpler tasks, like creating research outpost or observatory on the Moon. This task will create lots of challenges and people will get experience in making extraterrestrial settlements.

 

[hobbsyoyo]

I support that approach because I do not see it as an either/or proposition.