Road Trip to Mars

February 20, 2018

Way back when I was just starting to teach myself this science stuff in order to improve my science fiction, I discovered Google Earth included, in addition to a highly detailed map of the whole Earth, highly detailed maps of the Moon and Mars. I’m told the program now includes even more worlds to explore: Pluto, Europa, Titan… I imagine there’ll be a whole Google Solar System soon enough.

Anyway, back in those early days of my sciency self-education, I was playing with Google Mars, trying to get a better feel for Martian geography, when a little window popped up asking if I’d like driving directions to the location I’d just clicked on. I’m sure you can imagine my reaction: “Oh, yes please!” But of course this was only a glitch or something, and all the “get directions” options were grayed out.

There’s just something whimsically delightful about the idea that you could hop in your car and drive to space, drive all the way to Mars if you want. Apparently I’m not the only person who thought so. I wonder if those “get directions” options would still be grayed out today, now that Elon Musk has sent one of his old cars on a Mars-ward orbital trajectory.

I realize some people were a bit peeved about the whole first car in space thing. How tacky. How wasteful. Who’s this crazy billionaire throwing his money away on a stunt like that? I get it. To be honest, I kind of agree, and I would’ve preferred it if SpaceX had used the Falcon Heavy’s first test flight to launch something more pragmatic, like a weather satellite or something. Maybe that was too risky, given that a lot of people (myself included) expected the Falcon Heavy to blow up on the launch pad. I don’t know.

But what’s done is done, and while I have mixed feelings about sending a car to space, I do enjoy the whimsy of it. Also, I’ve been pleasantly surprised over the last few weeks by how many people are still talking about the “space car,” and how many of my friends and co-workers have suddenly taken an interest in space, how many of them are asking me about Elon Musk and SpaceX and Mars exploration. I doubt that would have happened if SpaceX had launched a boring old weather satellite or something aboard the Falcon Heavy.

Anything that gets people talking about space and science is a win in my book, but what do you think? Was sending a car to space stupid and wasteful? Totally awesome? Or do you have mixed feelings about it, like I do?

Correction

Thanks to Simon for giving me the heads up about this: Musk’s Tessla Roadster is not, strictly speaking, the first car in space. Click here for more info.


2017/2018 Mars Mission Update

February 5, 2018

So I’m going to take a short break from my Mars mission because there are a few other things I want to work on. But I am most definitely not done with Mars.

First off I have two more posts I want to write about dining on Mars. We’ve already talked about growing potatoes and other vegetables in Martian regolith, and we’ve also talked about entomophagy. But as a Mars colony continues to grow, the colonists may be able to sustain some more “luxurious” foods.

I also have two planetary protection papers set aside that I really want to read. One argues in favor of letting our Mars rovers enter regions where biological activity is suspected to be occurring. The other argues against it. I’m not sure what I’ll get out of these two papers, but comparing and contrasting the arguments should be interesting.

Lastly, I’ve been telling you that Mars had a rather violent history with water. The geological evidence suggests lots of flash flooding rather than the kind of stable, long-lasting bodies of water we see here on Earth. But I may have made a bit of a sampling error here because most of what I’ve been reading about focuses on the Tharsis Bulge and surrounding regions. I’ve heard that if I visit other parts of Mars—the Utopia Planitia region, for example—Mars’s history with water might start looking different. I don’t know. We’ll see.

I started this special Mars Mission because I felt like I didn’t know nearly enough about the Red Planet. At this point, I’d say I’ve learned a lot but still have a lot more to learn. So while I’m going to move on to some other research topics right now, I will be coming back to this fairly soon. And if anyone has suggestions for other Mars-y things I should check out, please let me know in the comments.


Sciency Words: Jeans Escape

February 2, 2018

Today’s post is part of a special series here on Planet Pailly called Sciency Words. Each week, we take a closer look at an interesting science or science-related term to help us expand our scientific vocabularies together. Today’s term is:

JEANS ESCAPE

Once upon a time, there was a molecule on Mars that dreamed of going to space. In fact, once upon a time there must have been a whole lot of molecules in the Martian atmosphere that wanted to go to space, and they apparently succeeded because today Mars’s atmosphere is mostly all gone.

Several factors must have contributed to the success of this molecule-scaled space program. One factor was temperature. The temperature of a gas is really a measure of the average velocity of the molecules in that gas. But remember, that’s the average velocity meaning some individual molecules may be considerably faster or slower than average.

As gas molecules bounce off each other, some of them may also gain or lose momentum, and in some cases a molecule might gain enough momentum to achieve escape velocity (11 kilometers per second on Earth, or 5 kilometers per second on Mars).

At that point, that molecule could achieve its dream and fly off into space (assuming it doesn’t collide with any other molecules on the way out). This can happen with virtually any gas on any planet, but it works best for light-weight molecules (like hydrogen or helium) on low gravity worlds (like Mars).

This process is sometimes called thermal escape, but in the scientific literature I’ve read it seems to be more commonly referred to as Jeans escape.

Sir James Hopwood Jeans was a British mathematician and astronomer. In the early 20th Century, he published prolifically on subjects ranging from star formation to blackbody radiation to the thermal properties of planetary atmospheres. It was this planetary atmospheres work that first led to the idea that a planet could gradually lose its atmosphere to space.

Or at least it was the first time we humans knew anything about it. The atmospheric gas molecules of Mars figured it out a long, long time before that.


Molecular Monday: Top 5 Chemicals on Mars

January 29, 2018

For today’s Molecular Monday post, I thought I’d try something a little different. I’m counting down my picks for the top five chemicals on Mars. These are chemicals that, in one way or another, are important to helping us understand the Red Planet better.

#5 Possible Methane
Several robotic probes have detected burps of methane on Mars, which could indicate ongoing biological or geological activity—either one of which would be a huge surprise on a world long thought to be both biologically and geologically dead. However, the methane could also be a contaminant leaking from the robots themselves. We’ll have to wait and see with this one.

#4 Hematite
Hematite is a rusty red colored mineral, also known as iron oxide or iron (III) oxide. Almost the entire surface of Mars is covered in hematite, giving the planet its distinctive color. But questions remain about where all this hematite came from. One thing we can be certain about is that Mars’s red color is only skin deep. When the Curiosity rover drilled a hole in the ground, it found the underlying layer was grey.

#3 Carbon Dioxide
Mars’s atmosphere is almost all carbon dioxide, which should help keep the planet warm, but the air is too thin to produce much of a greenhouse effect. As a result, Mars is a little too cold for human comfort. There’s also plenty of frozen CO2 (also known as dry ice) at the poles. Maybe someday we can release all that excess CO2­ and do to Mars what we hope not to do to Earth.

#2 Perchlorate Salts
The most noteworthy perchlorates on Mars are calcium perchlorate and magnesium perchlorate, but there are plenty of other flavors besides those two. Based on data collected all over Mars, it seems these perchlorate salts make up 0.5% to 1.0% of the Martian regolith; that makes the regolith extremely toxic to humans, and we need to figure out what to do about this problem before we can begin any serious colonization efforts. On the other hand, in the unlikely event that life already exists on Mars, perchlorates might (might!) make a good source of chemical energy, similar to the way oxygen is a good source of chemical energy for us.

#1 Water
Humans on Mars will not suffer from a lack of water. There are vast quantities of H2O frozen at the poles and buried in underground glaciers. And there’s little doubt that liquid water once flowed over the planet’s surface, carving river channels and chemically altering the rocks. However, a wet and watery Mars would have looked very different from modern Earth. Rather than standing lakes and rivers, Mars seems to have experienced violent flash floods, perhaps caused by melting and refreezing glaciers, followed by long periods of dryness. Still, the liquid water was definitely there, and there’s a distinct possibility that microorganisms could have started to evolve before the planet dried up completely.

So those are my picks for the top five most interesting and/or important chemicals on Mars. Let me know what you think of this list in the comments, and if people like it, maybe I’ll do something similar for other planets.

P.S.: Honorable mention to the polycyclic aromatic hydrocarbons (PAHs) from the Martian meteorite ALH84001. Like those methane burps, PAHs could either be an indicator of Martian life or a hugely embarrassing scientific mistake.


Sciency Words: Triangular Trade

January 26, 2018

Today’s post is part of a special series here on Planet Pailly called Sciency Words. Each week, we take a closer look at an interesting science or science-related term to help us expand our scientific vocabularies together. Today I’m really stretching my conception of science-related terms so we can talk about:

TRIANGULAR TRADE

When I was a kid, I had an extensive collection of cards from Star Wars: The Customizable Card Game. At one point, I was trying to trade with a friend to get his Millennium Falcon card, but I didn’t have anything my friend wanted. So we got a third person involved and set up a three-way trade. My extra Princess Leia card went to this third person, who then gave a rare star destroyer to my friend, who then gave me the Millennium Falcon I needed to complete my rebel fleet.

This was sort of like what happens in triangular trade. Like nerdy kids trading Star Wars cards (or non-nerdy kids trading, I don’t know, baseball cards or something), cities or regions or countries set up three-way trade arrangements for their exports. This kind of arrangement served as the basis for much of the world economy in the 18th and 19th Centuries, during the Age of Colonialism.

The most commonly cited example (unfortunately) is the slave trade, where the trade routes between Europe, Africa, and the Americas actually traced out a big triangle across the Atlantic Ocean. European nations exported manufactured goods to their African colonies, which then exported slaves to the American colonies, which then exported things like sugar, cotton, tobacco, etc to Europe.

Obviously triangular trade is more of a historical term than a sciency thing, but much like the word thalassocracy, I feel like this old, history-related term might become applicable again in a far-out, Sci-Fi future where humanity is spreading across the Solar System. And the reason I think that is because Robert Zubrin, one of the foremost Mars colonization advocates in the U.S., wrote about triangular trade in his book The Case for Mars and also in this paper titled “The Economic Viability of Mars Colonization.”

To quote Zubrin from his “Economic Viability” paper:

There will be a “triangle trade,” with Earth supplying high technology manufactured goods to Mars, Mars supplying low technology manufactured goods and food staples to the asteroid belt and possibly the Moon as well, and the asteroids and the Moon sending metals and possibly helium-3 to Earth.

So everybody wins! The people of Earth win, the colonists on Mars win, and all the prospectors and mine workers in the asteroid belt win! Even our moonbase wins (this part might seem counterintuitive, but the delta-v to reach Earth’s Moon from Mars is actually lower than the delta-v to reach the Moon from Earth). And this time, slavery isn’t involved!

Unless the high technology being exported from Earth includes robot slaves who then… hold on, I have to go write down some story ideas.


A House on Earth or a Ticket to Mars?

January 24, 2018

Whenever someone says something will happen in the next twenty years, you can take that as code for “I have no idea when this will happen, but I really hope it’ll happen soon!”

With that in mind, in the next twenty years the cost of sending a human being to Mars will become affordable for the average person. Or at least that’s the promise made by Elon Musk in his scientific paper/personal manifesto “Making Humans a Multi-Planet Species.”

In that paper/manifesto, Musk says, “In fact, right now, you cannot go to Mars for infinite money.” That’s a blunt way of putting it. Musk goes on to say that if Apollo-era technology were revived, it would cost about $10 billion per person to send humans to Mars. But Musk believes his company, SpaceX, can reduce the cost to a mere $200,000 per person.

That’s still a whole lot of money. Who can afford that? But before you dismiss what Musk is saying, consider this: the average person heading to Mars would not be going on a whim or as a tourist. Choosing to travel to Mars would be a major life decision. You’d be going there to stay, to help colonize the Red Planet, to start a new life on a new world.

That $200,000 price tag is comparable, according to Musk’s estimation, to the median average cost of buying a home in the U.S. So the choice we’d all have can be framed this way: would you rather buy a house on Earth or a ticket to Mars?

If I could ask Musk one question, it would be can I get a mortgage on my Mars ticket? Based on some of the other things Musk says in his manifesto, I suspect the answer would be yes, something like a mortgage would be possible.

I have to admit I’d have a hard time deciding what to do in this future Mr. Musk envisions. I’d probably choose to go to Mars, but I also really like my house on Earth. It would be hard for me to give that up. Hard, but not impossible.

So if we were all living twenty years from now, which would you choose: a house on Earth or a ticket to Mars?


Sciency Words: Chemofossils

January 19, 2018

Today’s post is part of a special series here on Planet Pailly called Sciency Words. Each week, we take a closer look at an interesting science or science-related term to help us expand our scientific vocabularies together. Today’s term is:

CHEMOFOSSIL

On Wednesday, I made up a bunch of numbers for the odds that we will find life on (or bring life to) Mars. The odds, in my inexpert judgment, are pretty low for finding anything presently alive on Mars, but I’d say there’s a 50/50 chance we’ll find the fossilized remains of life that existed there in the past. Now if only our rovers were equipped with digging gear!

But after writing Wednesday’s post, I learned that there are, in fact, many different kinds of fossils, including body fossils, trace fossils, ichnofossils, and chemofossils. And according to this article by Claire Cousins, a planetary scientist working on the European Space Agency’s upcoming ExoMars rover, it’s these chemofossils that will probably be our first real evidence of ancient Mars life.

The word chemofossil is, as you may have guessed, a combination of the words chemical and fossil. I was unable to find out who coined the term, but it seems to have happened fairly recently. According to Google Ngrams, it starts appearing in literature in the 1970’s.

Chemofossils are the telltale chemicals left behind by dead and decaying biomaterial. Even if an organism becomes totally decomposed, there may still be a sort of residue that suggests some sort of past biological activity. A good example, which Cousins cites in her article, are amino acids that share the same chirality.

Finding amino acids on Mars would be mildly interesting, but amino acids can come from just about anywhere. However, if those amino acids all have “left-handed” chirality (or “right-handed” chirality), well… the only natural phenomenon we know of that picks and chooses the chirality of amino acids is life.

Now since I’m still in the mood for making up numbers, I’m going to say there’s a 99% chance someone will announce they’ve detected chemofossils on Mars, BUT we will spend the following decade or two arguing about whether or not they really did. As Claire Cousins writes, discovering life on Mars “[…] will be a gradual process, with evidence building up layer by layer until no other explanation exits.”

In other words, I doubt that discovering chemofossils will definitively prove that life once existed on Mars. But I do think chemofossils will be the first “layer of evidence” we find.