“Solar-wind erosion is an important mechanism for atmospheric loss,”

November 6, 2015 8:54 AM

NASA Mission Reveals Speed of Solar Wind Stripping Martian Atmosphere [mars.nasa.gov]

NASA's Mars Atmosphere and Volatile Evolution (MAVEN) mission has identified the process that appears to have played a key role in the transition of the Martian climate from an early, warm and wet environment that might have supported surface life to the cold, arid planet Mars is today. MAVEN data have enabled researchers to determine the rate at which the Martian atmosphere currently is losing gas to space via stripping by the solar wind. The findings reveal that the erosion of Mars' atmosphere increases significantly during solar storms. The scientific results from the mission appear in the Nov. 5 issues of the journals Science and Geophysical Research Letters. [YouTube]

posted by Fizz (41 comments total)

I'll just be over here turning my rocket back into a wind turbine.
posted by parmanparman at 9:02 AM on November 6, 2015 [1 favorite]

OK, I feel mean/pedantic for saying this, but: duh ? I don't recall exactly where I read this, but it was a critique of the "colonize mars" sci fi (when that idea was still sci-fi, not in some early planning stages of feasibility like it is now). The point is, that since Mars lacks a molten iron core that spins (to generate magnetic fields to deflect the solar wind), any type of terraforming on Mars is destined to fail. People would have to live under permanent housing etc, no reactor that Quaid could start would ever change that reality.
posted by k5.user at 9:05 AM on November 6, 2015 [1 favorite]

any type of terraforming on Mars is destined to fail. People would have to live under permanent housing etc,

Just put up a garbage bag with some duct tape. Should be fine. It worked for Matt Damon.
posted by Fizz at 9:12 AM on November 6, 2015 [8 favorites]

> "It worked for Matt Damon."

On a side note, because it was in a movie theater with other people present, I was able to restrain myself from shouting at the screen, "If there's hardly any atmosphere on Mars a windstorm wouldn't throw around heavy equipment or knock over the ship!" "And if it could knock over the ship, why the hell wouldn't you take the incredibly simple precautions that would prevent it from doing so?!" "Wait, you didn't clean the perchlorate out of the soil before growing potatoes in it? YOU'RE DEAD, MATT DAMON, YOU JUST DESTROYED YOUR THYROID WITH YOUR POISON MARTIAN POTATOES!" and so on.

I was extremely surprised to discover that my main objection to that movie was that it was, apparently, not nearly nerdy enough for me.
posted by kyrademon at 9:21 AM on November 6, 2015 [5 favorites]

Maybe hit it with a large moon to reliquify the core and keep it circulating with tidal forces. Might take a few years for the surface to cool down...
posted by rikschell at 9:23 AM on November 6, 2015

I was extremely surprised to discover that my main objection to that movie was that it was, apparently, not nearly nerdy enough for me

The problem with competence porn is that it makes people desire more detailed levels of competence being depicted.
posted by nubs at 9:24 AM on November 6, 2015 [18 favorites]

poor mars. sweet little guy getting all his air sucked away. (using mythological gender terms, lol)
posted by Annika Cicada at 9:24 AM on November 6, 2015 [1 favorite]

Nah, just keep throwing comets at it to replenish the atmosphere that gets stripped away. We'll never run out of comets, right?
Or hell as long as we have access to godlike technology where terraforming is a possibility, just create an artificial magnetic field. You know, like in the documentary Spaceballs.
posted by Eddie Mars at 9:26 AM on November 6, 2015 [5 favorites]

People always talk about "Terraforming" Mars, but no-one wants to face up to the fact that climate change is "Veneraforming" the Earth. Given this obvious fact, isn't it possible that the Venusians have secretly taken control of Earth society? And doesn't that hypothesis perfectly fit the other phenomena we see all around us - runaway capitalism reducing us all to hyper-productive worker-slaves without human rights, desperately producing and consuming more and more resources to fund our overlord's desire for an unstoppable rise in carbon emissions? Also the strange, "otherworldly" actions of our politicians, whose policy statements read more and more like they are from a different planet? I think we can all agree that the ONLY possible conclusion is that we are being ruled by lizard people from Venus, cunningly disguised as humans. Indeed - for all I know - YOU could be a lizard person too. A lizard person would probably dismiss this comment as "crazy talk" and the commenter as a "pathetic, attention seeking moron". If only MeFi had implemented some kind of "polling" feature, as seen on other, competitor websites - whereby you could choose one of the following mutually exclusive options:

-- vote #1 quidnunc kid
-- I am a Venusian lizard person
posted by the quidnunc kid at 9:27 AM on November 6, 2015 [47 favorites]

The ozone hole is where they will put their giant, atmosphere sucking straw.
posted by Oyéah at 9:31 AM on November 6, 2015 [1 favorite]

100 grams every second is only around 3200 metric tonnes per year. We add 18.4 *billion* metric tons of CO2 per year to Earth's atmosphere. Maintaining an atmosphere on human timescales wouldn't actually be all that hard for an industrialized society. It's just if nothing was done for a few million years the losses start to add up.
posted by Zalzidrax at 9:34 AM on November 6, 2015 [4 favorites]

The point is, that since Mars lacks a molten iron core that spins (to generate magnetic fields to deflect the solar wind), any type of terraforming on Mars is destined to fail.

I love imagining aliens seeing the magnetic force field that protects the Earth's atmosphere from this and thinking, "Surely that can't be natural, can it?!"

"And what about that gigantic moon stabilizing the axial tilt?"
posted by straight at 9:36 AM on November 6, 2015 [10 favorites]

God Sol, can't you suck?
posted by a lungful of dragon at 9:37 AM on November 6, 2015

The point is, that since Mars lacks a molten iron core that spins (to generate magnetic fields to deflect the solar wind), any type of terraforming on Mars is destined to fail.

Yep. Today, with a very thin atmosphere, Mars is losing 3200 metric tonnes of gas a day. With a thicker atmosphere, it would lose a lot more. The theory of the solar wind stripping Mars of its atmosphere isn't new, which is one reason MAVEN was built -- to confirm or deny that theory. Looks like a rock solid confirmation.

This basically kills Blue Mars. As long as Mars had a liquid core able to act as a dynamo, it could fend off the solar wind. Venus doesn't because venus doesn't spin fast enough, but Venus has a much deeper gravity well holding that atmosphere in. Mars does spin fast enough -- the Martian Sol and Earth day are only 37 minutes and change different, but with a solid core, there's no flux interaction. What little magnetic field Mars has today is the permanently magnetized portions of the crust -- evidence that Mars both had a magnetic field and that the field had switched polarity many times, much as the Earth's magnetic field does.^*

Not only does this make the atmosphere untenable, it's hard on Ozone, so UV exposure is a real problem, and large solar particle events can actually reach the surface. Suck time if you're not shielded from that. Radiation does in low Mars orbit are about 22mrad, this is nearly three times the radiation dose you get from the ISS, but the real problem is solar flares -- if one cranks a CME right at Mars, the rad flux increases dramatically, because there's no magnetosphere to deflect it around the planet.

The reason the atmosphere is mostly CO₂ is the higher molecular mass. Hydrogen, Helium and Oxygen, being light, are easier to move.

I think Neil DeGrass Tyson said it. "If we have the technology to terraform Mars, we have the technology to fix Earth."


* Given the accelerating movement of the Geomagnetic North Pole to the Northwest, it's possible that we're on the verge of a magentic field reversal right now. That's just speculation, but it has moved as much between 2001-2007 as it did between 1900-1950.
posted by eriko at 9:42 AM on November 6, 2015 [4 favorites]

The problem with competence porn is that it makes people desire more detailed levels of competence being depicted.

No, the real problem is that it conditions us to expect unrealistic amounts of competence from the people around them and to be unsatisfied otherwise. Talk about a recipe for misery.

Edit: apparently I'm not competent enough to come up with an original comment
posted by droro at 9:48 AM on November 6, 2015 [1 favorite]

I think Neil DeGrass Tyson said it. "If we have the technology to terraform Mars, we have the technology to fix Earth."

...but we don't, and we probably don't.
posted by Wolfdog at 9:57 AM on November 6, 2015

Let's face it, competence porn is no longer even shocking. What used to exist only in magazines quietly tucked under the beds of nerdy teenagers can now be accessed by anyone with a computer. It's normalized to the point where many children are getting their first auto maintenance lessons off of YouTube. Studies show that kids as young as 11 watch competence porn, and for many teens it is the primary way they learn to, so to speak, "do stuff". They Google things like "teach yourself to knit" or "home rocketry experiments" to figure out exactly what those are and how to go about doing them, bypassing what they get taught at school or by their parents.

The consequences have been severe. These videos show a one-sided perspective of accomplishment solely from the point of view of the capable -- with no emphasis on giving pleasure to the incompetent. Many of today's more ineffectual youths now have issues they directly relate to competence porn, such as struggling to fix their own plumbing or cut their own hair. But this is not the end of competence porn’s influence. While the previous generation watched competence porn simply to learn what a ramscoop or a sparkplug was, a new generation is actually watching it for career advice. They see famous competence porn stars racking up thousands of Twitter followers, and start to see being competent as a legitimate career option. Which is fine if people know what they're getting into, but most of these kids have no idea what the realities of the competence industry are like.

This isn’t to suggest that all competence porn is bad. Many people enjoy watching competence porn, whether they do so alone or share it with their partners. What is bad, though, is allowing the unreasonable expectations presented in a fantasy competence scene to infiltrate the home in a way that negatively impacts children and teens.
posted by kyrademon at 10:11 AM on November 6, 2015 [13 favorites]

Maybe hit it with a large moon to reliquify the core and keep it circulating with tidal forces.

We aren't really doing anything useful with Venus right now. I say smack Venus and Mars together and see what happens
posted by happyroach at 10:12 AM on November 6, 2015 [2 favorites]

The thing the "let's fix Earth" and "let's terraform Mars" arguments have in common is that neither one is going to happen.
posted by The Whelk at 10:16 AM on November 6, 2015

"maybe you should spread the butter ON the toast, instead of just taking alternating bites of bread and a stick of butter unwrapped like a banana." Like I'm some kind of ENGINEER that's supposed to be able to figure these things out

To optimize your morning, I'd like to point out that you don't actually need the bread.
posted by justsomebodythatyouusedtoknow at 10:36 AM on November 6, 2015 [2 favorites]

justsomebodythatyouusedtoknow, you have a bright future in Wisconsin.
posted by The Gaffer at 10:43 AM on November 6, 2015 [1 favorite]

Maybe hit it with a large moon to reliquify the core and keep it circulating with tidal forces. Might take a few years for the surface to cool down...

Nah, just nuke it.
posted by cosmic.osmo at 10:47 AM on November 6, 2015

Metafilter: giving pleasure to the incompetent
posted by CynicalKnight at 10:55 AM on November 6, 2015 [1 favorite]

Kyrademon, I'm pretty sure you're joking, but the sad thing is I feel there's enough there to form a totally earnest argument that learning to do something on YouTube rather than in school is somehow damaging to children. I don't buy a word of it but I can totally believe someone could make that argument
posted by Mr.Encyclopedia at 11:01 AM on November 6, 2015

I'm printing this thread and pinning it up on my bedroom wall so that I may better gaze upon it with stary-eyed adoration.
posted by The Legit Republic of Blanketsburg at 11:03 AM on November 6, 2015

We aren't really doing anything useful with Venus right now. I say smack Venus and Mars together and see what happens

Dropping Mars down the gravity well toward Venus would have to be very carefully timed, as too close a pass to us on its way down might give the earth-moon system a tug it doesn't need.

More importantly, I would imagine you're thinking of crashing something big into Mars to impart the necessary delta-v to send it sliding down the well. If you have the capacity to lob something large enough at Mars to do that, might it not be better to try and put said big thing in orbit around Mars , as close as possible while being outside the rouche limit, and try and out some tidal forces to work on the Martian core?
posted by The Legit Republic of Blanketsburg at 11:11 AM on November 6, 2015

...but we don't, and we probably don't.

This was Tyson's point, actually. The idea that we need to terraform Mars in case we destroy the Earth's habitability is silly, because if we *could* terraform Mars, re-terraforming Earth would be a piece of cake. We can't, so we can't.

There are things that can destroy Earth -- Sun expands into a red giant, solar mass black hole whips through the solar system and fucks up all the orbits, gamma ray burst up close -- but they all destroy Mars just as badly. The few things that might whack the Earth and leave Mars around, like a large impactor, are things that we can (if we go all in on it) defend against now -- just get enough ΔV to the thing that's going to hit us, and nudge it away.^*

The only thing Humanity would do to Mars is wreck it just as badly as they have the Earth.



* Detection is huge. The more time we have, the more ΔV we can launch and the less ΔV that we need to impart on the impactor to make it miss.

If it's in a hyperbolic or near hyperbolic orbit, just push into a path where it gets a gravity assist from the Earth, and throw the bastard right out of the Solar System. If it's on a closed orbit, you might need to push it to miss, then push it at perihelion or aphelion to make sure it stays away.

But with enough time, this isn't that hard -- certainly not compared to terraforming a planet. Again, the farther away it is when we start pushing, the less pushing we need to do. We see it a week out? We're doomed. Of course, the people on a theoretical Mars colony would, of course, die out when the supply train from the Earth disappears with the Earth.
posted by eriko at 11:48 AM on November 6, 2015 [2 favorites]

To flip the argument around, if we try to figure out how to terraform and fail, we might yet figure out how to re-terraform Earth from what we learn.
posted by Zalzidrax at 12:28 PM on November 6, 2015

There are things that can destroy Earth

Anybody read Neal Stephenson's Seveneves yet?
posted by sidereal at 1:21 PM on November 6, 2015

You guys are looking at this the wrong way. The problem isn't Mars, it's the solar wind. The answer is clear. To terraform Mars we have to blow up the sun.
posted by dephlogisticated at 2:33 PM on November 6, 2015 [2 favorites]

the people on a theoretical Mars colony would, of course, die out when the supply train from the Earth disappears with the Earth.

The people on an actual Mars colony would die. The people on a theoretical Mars colony would live comfortably, their thriving industrial and agricultural systems humming along under giant sapphire domes manufactured directly from indigenous rock using solar power.
posted by sfenders at 3:15 PM on November 6, 2015 [3 favorites]

Maybe someone should build a Mars colony in 2nd, umm, Third Fourth Life. It could be realistic enough, with random dust storms and falling alien planet-sterilizing devices, but a great and wonderful magnetic field. All the people who've signed up for Mars One could play it in real time. I loved the backgrounds in The Martian.
posted by sneebler at 4:26 PM on November 6, 2015

sidereal, I just started Seveneves. I've been admiring the way Stephenson set up the problem he's setting out to solve without humans to blame for why we have to leave Earth. It's poignant, all in all, so far. Ol' buddy librarianavenger washed her hands of the book, saying she'd rather have had a series of entertaining essays on the topic from Stephenson.
posted by gusandrews at 4:48 PM on November 6, 2015

Anybody read Neal Stephenson's Seveneves yet?

Yep. Biggest takeaway? Don't let Hillary on the space ark.
posted by leotrotsky at 6:33 PM on November 6, 2015

Has anybody heard of any semi-plausible scenarios for giving Mars some kind of electromagnetic forcefield ala Earth? The lack of such protection has long been one of the major hurdles in terms of planning widespread Martian colonization, even before this information from the MAVEN team.

Even putting aside the atmospheric stripping, the solar wind exposes the Martian surface to way more ionizing radiation and electromagnetic interference than humans really want to have to deal with, so one of the goals in any hypothetical project to render Mars truly habitable is to do something to block most of that. Has anyone heard of a plausible (even if not actually feasible) way of accomplishing such a goal?
posted by Anticipation Of A New Lover's Arrival, The at 9:17 AM on November 7, 2015

I have a plan…build an array of tunnels to the center of Mars, then gradually heat up the core with fusion-power lasers, over several thousand years...
posted by littlejohnnyjewel at 10:30 AM on November 7, 2015

If it's in a hyperbolic or near hyperbolic orbit, just push into a path where it gets a gravity assist from the Earth, and throw the bastard right out of the Solar System.

Oh, I remember this, this is from the classic Astrophysics And The Art Of Forum Moderation.
posted by Jon Mitchell at 4:08 PM on November 7, 2015

Just be sure to give the dude from Aerosmith some anti-emitic before sending him up.
posted by mcrandello at 9:10 PM on November 7, 2015

Has anybody heard of any semi-plausible scenarios for giving Mars some kind of electromagnetic forcefield ala Earth?

Neither motors nor electrical engineering are my field at all but maybe if the core was even slightly molten near the mantle, and you had a few planetary-scale strips of superconductor and a fuckton of power it would be possible to restart the core as a colossal induction motor?

First bonghit that came to mind, anyway.
posted by Ryvar at 12:04 AM on November 8, 2015

any type of terraforming on Mars is destined to fail

An old joke:

Lecturer: "And the sun will render Earth uninhabitable in only a billion years."
Student: "Wait, did you say million!?"
"No, billion."
"Whew!"

Updated for Metafilter:

NASA press release: "The solar wind strips the mass of a large comet away from Mars every three million years"*
Metafilter: "Wait, did you say billion?"
"No, million."
"What's even the point, then?"

* 10e13/.1/3600/24/365 = 3e6
posted by roystgnr at 8:24 AM on November 8, 2015

Dropping Mars down the gravity well toward Venus would have to be very carefully timed, as too close a pass to us on its way down might give the earth-moon system a tug it doesn't need.


Honestly, I'd rather move Venus up the gravity well. That way, if we change our minds about knocing it into Mars, we can have it in an orbit inside the habitability zone. Of course in eitgher case you'd want to be careful about adjusting the orbit.

More importantly, I would imagine you're thinking of crashing something big into Mars to impart the necessary delta-v to send it sliding down the well. I

No need to be that rambunctious. Thanks to transfer of momentum, close orbital passes by largish asteroids can be used to increase or decrease the orbital velocity of a planet. We've already calculated how many passes would be needed to move the Earth outward when the sun gets too hot, and there's no reason to think it wouldn't work on Mars or Venus.

Of course there's always the possibility that doing s would cause chaotic alterations in the orbits of other planets, like say, Mercury, but at least it works in theory.
posted by happyroach at 9:09 PM on November 8, 2015