Tag: Space

A House on Earth or a Ticket to Mars?

~ J.S. Pailly ~ 15 Comments

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

~ J.S. Pailly ~ 8 Comments

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.

Life on Mars: What Are the Odds?

~ J.S. Pailly ~ 12 Comments

So… is there life on Mars? I don’t know, but after everything I’ve read and seen and learned about the Red Planet, I feel like making up some numbers.

I’m going to say there’s a 10% chance that life exists on Mars today. Mind you, this is not intelligent life. It’s not even complex, multi-cellular life. No, I’m just saying there’s a 10% chance that some kind of microorganism is there, eking out an existence near the Martian R.S.L.s or in the permafrost near the Martian poles. And maybe we’ve already detected the first signs of these microorganisms’ activity.

But the odds of that are pretty low, in my opinion. I think there’s a much better chance—let’s say a 50% chance—that Mars supported life at some point in the past, and that we’ll find the fossilized remains of ancient Martian organisms preserved in rock. We’re probably still only talking about microorganisms (or rather microfossils), but given that Mars hasn’t been geologically active in a long time, those fossils should be extremely well preserved.

Lastly, I think there’s a 90% chance that, regardless of whether or not Mars supported life in the past or present, it will support life in the future. Human life, to be specific (as well as plant life and maybe some edible bugs). Maybe it’ll be nothing more than a small research station, or maybe it will be a full-fledged colony. But I’m 90% sure we’ll get there. I say this because a lot of very smart people (and a handful of very rich people) seem to be pretty determined to make it happen.

Anyway, these are my best guesses about the odds of finding life on (or bringing life to) Mars. Do you agree with my rough estimates? Do you think I’m way off? Let me know in the comments!

Molecular Monday: Jarosite on Mars

~ J.S. Pailly ~ Leave a comment

Today’s post is part of a bi-weekly series here on Planet Pailly called Molecular Mondays, where we take a closer look at the atoms and molecules that make up our physical universe.

Over the last few months, I’ve been trying to get to know the planet Mars better. There’s some pretty clear evidence that Mars used to be a different kind of planet, a wetter and more watery sort of world… but perhaps not in the way you might have expected.

Many of Mars’s rocks seem to tell a similar story about that wet, watery past. That story usually begins something like this:

We’ve already looked at Mars’s sedimentary basaltic rocks. Such a thing would be almost a contradiction in terms on Earth. Sedimentary rocks are made by flowing water; basalt is destroyed by water. So how could a rock be both basaltic and sedimentary?

Now let’s take a look at another rock that’s almost self-contradictory: jarosite. Jarosite is a potassium/sulfur/iron-containing mineral with the chemical formula KFe3(OH)6(SO4)2. It typically forms in wet, acidic environments by the oxidation of iron sulfides. If you don’t understand what that means, that’s okay; I don’t fully understand it either. The important thing is that jarosite forms in water; but jarosite is also destroyed by water. It breaks down into simpler compounds if exposed to water for long periods of time. That makes jarosite pretty hard to find on Earth, but of course it’s surprisingly common on Mars!

In 2004, the Opportunity rover discovered jarosite—lots of jarosite—in the Meridiani Planum region (incidentally, the same region where Airy-0 is located). According to a NASA press release at the time: “Jarosite may point to the rocks wet history having been an acidic lake or an acidic hot springs environment.”

But whatever was happening in Meridiani Planum, the region must have dried up pretty quickly. According to the abstract of this paper, also from 2004, “[…] the presence of jarosite combined with residual basalt at Meridiani Planum indicates that the alteration process did not proceed to completion, and that following jarosite formation, arid conditions must have prevailed.”

Before I started all this Mars research, I imagined ancient Mars as a very Earth-like place, with standing oceans and lakes and gently flowing rivers. I guess there still could have been a time like that in the very beginning, but most of Mars’s history with water seems to have been far more sporadic and violent than that, with lots of flash flooding (perhaps caused by melting glaciers) and very brief wet spells followed by long periods of dryness.

At least that’s my impression at this point in my research.

Sciency Words: Airy-0

~ J.S. Pailly ~ 6 Comments

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:

AIRY-0

Airy-0 is a small crater on Mars. There’s nothing particularly strange or noteworthy about it. Mars has lots of craters. Or at least, Airy-0 wouldn’t be noteworthy if not for some arbitrary decisions made on Earth over the course of the last few centuries.

In the 1830’s, Earth-based astronomers wanted to know the length of a Martian day, so they picked a dark, easily-identifiable surface feature and used that as a reference point to determine the planet’s rate of rotation. 19th Century astronomers also decided to use that dark surface feature to calculate latitude lines on the Red Planet. In other words, that dark feature (now known as Sinus Meridiani) became the reference point for the Martian prime meridian.

Then in the 1970’s, when NASA’s Mariner 9 space probe began sending back the first detailed maps of Mars, a specific crater within the Sinus Meridiani region was chosen to serve as a better, more precise reference point for the prime meridian. That crater was named Airy-0 in honor of George Biddell Airy, the astronomer who built the Airy Transit Circle telescope at the Greenwich Observatory in England.

I find this extremely fitting. The location of Airy’s telescope is used to define Earth’s prime meridian, so it makes sense that Airy’s crater on Mars would be used to define the prime meridian of Mars. But unfortunately, there seems to still be some uncertainty about Airy-0’s exact location.

Apparently the crater is small enough that space craft can have trouble locking onto it from orbit, and according to this paper from 2014, it turns out Airy-0 is approximately 47 meters east of where it was previously estimated to be. That’s a discrepancy of 0.001º latitude, which may not seem like much, but it’s enough to be problematic for science.

Three pictures of Airy-0 in increasingly high resolution over the past few decades. Airy-0 is the large crater in the top of each picture. Image courtesy of Wikipedia.

So Airy-0 will continue to be subject to intense scrutiny by us Earthlings, not so much because of anything intrinsically special about it but because, for the purposes of Martian cartography and Martian timekeeping, we really, really need to know exactly where Mars’s prime meridian is.

Why I’m Drawing Mars’s Scar

~ J.S. Pailly ~ 4 Comments

When I first started drawing silly cartoons of the planets… err—I mean highly technical diagrams of celestial bodies—I had to chose which features to emphasize and which to leave out. For Mars, I ended up showing that distinctive orange/red coloration. What more would I need to show?

I decided to leave out the long, jagged scar cutting across the planet’s surface, in part because I thought it looked ugly. Maybe Mars feels the same way. In 1971, when NASA’s Mariner 9 space probe arrived to create the first detailed maps of the planet’s surface, Mars threw up a global dust storm unlike anything humans had ever seen before, completely obscuring all the planet’s surface features.

But as I’ve gotten to know Mars better, I’ve realized that Mars’s scar—the Valles Marineris canyon system, as its officially known—is really one of the Red Planet’s most important features. It’s as distinguishing a feature as the Great Red Spot on Jupiter or the giant heart on Pluto.

Valles Marineris is believed to have started out as a giant graben, or perhaps multiple smaller grabens, and it may have been one of the last geologically active regions on Mars (along with the neighboring Tharsis bulge). The end of Mars’s geological activity would have been related to the collapse of the planet’s magnetic field, which led to the loss of the Martian atmosphere and the rapid freezing/boiling of Mars’s oceans. If Mars ever had anything resembling an Earth-like biosphere, that would have been destroyed around that time too.

In other words, the story of how Mars got that scar may have a lot to tell us about Mars’s past, about the world Mars used to be. Over the last few months, I’ve experimented with different ways to depict Valles Marineris in my drawings. This is my favorite version:

Going forward, I’m going to include Valles Marineris in all my drawings of Mars (unless, of course, we’re highlighting a completely different region of the planet). Valles Marineris is just too important a thing to leave out. And also, scars are nothing to be ashamed of.

Living on Mars Time

~ J.S. Pailly ~ 2 Comments

In the last two episodes of Sciency Words, we’ve been talking about timekeeping on Mars. A “day” on Mars is slightly longer than a day on Earth, and a Martian calendar would require a whole lot of leap years. And (spoiler alert) the Sciency Words post for this coming Friday will also be Mars-time related.

But in the course of my research, I came across this TED Talk by NASA engineer Nagin Cox. She’s one of the people who had to actually live on Mars time as part of her job, and I think she has a lot of valuable insight into what the Martian experience is really like.

For me, one of the major highlights of this is the part where Ms. Cox shows us that she’s wearing two watches: one set to Earth time and one modified to run slower, presumably 2.7% slower, to match Mars time. I’d always assumed this was a computer thing; I didn’t realize physical Mars watches were made.

It would seem that, at least as far as NASA’s Mars watches are concerned, the Martian “day” is still divided up into 24 “hours.” It’s just that these hours are 2.7% longer than hours on Earth. Martian minutes and seconds are also 2.7% longer. Obviously this is inconsistent with S.I. units, but I imagine it cost a lot less to modify an existing watch to run 2.7% slower than it would to design a whole new watch that includes an extra 39 minutes and 35 seconds in a day.

Anyway, for those of you who really want to know what it would be like to live on Mars, I think this is worth watching. It’s about 14 minutes long. To be more precise, it’s 13 minutes and 48 seconds in Earth time, or 13 minutes and 26 seconds in Mars time, assuming I did my math correctly.

And if you’re looking to get a Mars watch of your own, turns out there’s an app for that (click here for the Android version and click here for iPhone).

Sciency Words: The Darian Calendar

~ J.S. Pailly ~ 8 Comments

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:

THE DARIAN CALENDAR

In 1986, aerospace engineer and polymath Thomas Gangale published a paper titled “Martian Standard Time” in which he outlined a calendar which could be used by Martian colonists in the future. Gangale named this calendar the Darian calendar after his son, Darius, and he describes the idea in greater detail on his website (click here).

According to the Darian calendar, the Martian year begins on or around the vernal equinox, when the sun is directly above the planet’s equator and spring is just beginning in the northern hemisphere. Because the Martian year is nearly twice as long as Earth’s, we get twenty-four months rather than twelve.

The names of the months alternate between the Latin and Sanskrit names for the Zodiak constellations. Thus the month of Sagittarius (the first month of the year) is followed by Dhanus, then Capricornus, then Makara, then Aquarius, and so on until you get to Scorpius and then Vrishika (the last month of the year). Each month has 28 days… sorry, 28 sols… except Kumbha, Rishabha, Simba, and Vrishika (the 6th, 12th, 18th, and 24th months, respectively) unless it’s a leap year, in which case Vrishika is 28 sols long.

And regarding leap years, there are a lot of them: six every decade, so leap years are actually more common than regular years. But then every hundred years we have to take a leap sol away, and then every five hundred years we have to put it back—I know, this is starting to sound complicated, but it’s not that much worse than what we have to do to keep the Gregorian calendar balanced on Earth.

If you’re wondering about the days of the week (I mean, sols of the week), Gangale thought of that too. Each Mars week is made up of seven sols with names that hark back to the ancient Latin names for the days of the week:

Sol Solis (Sunday)
Sol Lunae (Monday)
Sol Martius (Tuesday)
Sol Mercurii (Wednesday)
Sol Jovis (Thursday)
Sol Veneris (Friday)
Sol Saturni (Saturday)

Also, Gangale designed his calendar so that each date always falls on the same sol of the week. The 1st of Sagittarius is always a Sol Solis, for example. That’s pretty convenient, I think, although it also works out that every month the 13th is always on a Sol Veneris (a Friday), which seems rather unlucky.

The question, of course, is will Martian colonists actually adopt this as their calendar? I don’t know, but it seems certain aspects of the Darian system—such as the way it handles leap years—have already been borrowed for other Mars-related research purposes.

Molecular Monday: Mars Burps Methane

~ J.S. Pailly ~ 6 Comments

Happy New Year’s, and happy Molecular Monday too! I can’t think of a better way to start off 2018 than with a blog post about molecules. Well, no… I probably could, but my schedule says this is what I’m supposed to blog about today, so here we are!

If you’re looking for life on other planets, one of the most common pieces of advice you’ll get is “follow the water.” That is, of course, assuming you can find any liquid water in the first place. But maybe another option is to follow the methane.

The planet Mars seems to have a bit of a methane mystery going on. Mars will sit there, all quiet and normal, for years at a time, but then suddenly…

… and then suddenly all this methane shows up in the planet’s atmosphere.

The most notable of these methane burps occurred in late 2013 and early 2014, when the Curiosity rover started detecting methane levels ten times higher than normal. Where did all this methane come from?

One boring possibility is that it came from the rover itself, a result of some kind of leak. It’s also possible that a meteorite just happened to land near Curiosity, and that this meteorite just happened to be carrying a lot of organic material. Or maybe there was some kind of surprise geological activity nearby that vented methane from somewhere underground.

But the most intriguing possibility is that the methane was produced by biological activity. That is, after all, how most atmospheric methane is produced on Earth. And I recently found this paper offering a possible way to determine once and for all (maybe, hopefully, fingers crossed) if Mars’s methane really does come from a biological source.

From what I gather, having only skimmed through this paper (sorry, I was trying to read this on New Year’s Eve, and there were margaritas), the key is to follow the methane then follow the hydrogen. So the next time Mars burps up some methane, the ratio of methane to hydrogen in the air might reveal the methane’s true source.

Sciency Words: Sol

~ J.S. Pailly ~ Leave a comment

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:

SOL

If you’ve read or seen The Martian or pay any close attention to NASA’s ongoing Mars missions, you probably already know what this word means. A sol is a Martian day. The word itself is a shortening of the term solar day, the period of time it takes for a planetary body to rotate once in relation to the Sun.

Technically we could apply this term to any planetary body that experiences regular day/night cycles. A solar day on Earth is 24 hours, as you probably already knew. A solar day on Jupiter is about 10 hours long, and a solar day on Venus is roughly 2,802 hours (or 116.75 Earth days).

But for whatever reason, the shortened form “sol” seems to be used only in reference to Mars, where it equals 24 hours, 39 minutes, and 35 seconds. It’s weird how close a Martian sol is to an Earth day, isn’t it?

Starting with the Spirit and Opportunity missions, NASA has actually made some of its scientists and engineers work on Mars time rather than Earth time. That extra 39 minutes and 35 seconds obviously messes with people’s sleep cycles, eating habits, and social calendars. But it’s important for the crew in mission control to be in sync with the robotics activities taking place on Mars.

Since humans have a natural tendency to be playful with language, a few clever new words have emerged as a result:

  • Yestersol: the sol prior to the current sol, formed by analogy with yesterday.
  • Tosol: the current sol, formed by analogy with today.
  • Solmorrow: the sol after the current sol, formed by analogy with tomorrow.
  • Nextersol: an alternative to solmorrow, presumably formed by analogy with yestersol. Personally I like the sound of solmorrow better.

What really pleases me about these terms is that we haven’t even landed the first humans on Mars yet, and we’re already coming up with vernacular lingo for the Red Planet. Could this be a preview of how Mars colonists might actually speak one day… I mean, one sol? And how else might we adapt human culture to the new environment? I for one am looking forward to Mars’s version of Shakespeare.

Next time on Sciency Words: it’s one thing to know that a Martian day is called a sol, but how the heck are you supposed to find tosol’s date on a calendar?