Rhinocrisy

One of my favorite conspiracy theories is that NASA is deliberately false-coloring images so that Mars appears to have a red sky, to cover up the fact that it’s actually blue there. I’m not exactly sure why NASA would be doing this, but I’ll admit I’ve been disappointed by the color of the sky (and the ground) in Mars photos, so I’m on board! Let’s deconvolve:

First, for the uninitiated, our a priori expectation should be a blue sky. The sky everywhere should be blue, because the color of the sky is the product of Rayleigh scattering - which is basically to say, the atmosphere tends to scatter higher-frequency light more than it scatters lower-frequency light. If you look up at any random part of the sky that isn’t the sun, the light you’re seeing is light that has scattered off some part of the atmosphere in that direction; in space, that light would have gone straight to its target, and you would see no light coming from that direction. Since the atmosphere scatters violet light more than red light, this, combined with our human visual system’s spectral bias (weak in the blue end of the spectrum), results in our seeing the sky as blue. This simple phenomenon should apply equally well to all atmospheres.

So it’s a bit glum when we’re told that Mars has a red sky - red because it’s full of thick, choking dust. Well, poop. But maybe it’s not so! Maybe NASA is attempting to pull the dust over our eyes, and Mars is really true-blue. Fortunately, we can verify for ourselves. NASA puts up “raw” JPEGs of all the data the rovers send back. The relevant images are the “PANCAM” ones, which apply a series of fairly narrow bandpass filters before the CCD capture (that is, each filter captures an image of the scene at a specific wavelength of light).

The NASA “true color” images are generated by the PANCAM group at Cornell; their methodology is quite rigorous. The naive method (employed by most conspiracy theorists, notably Keith Laney) is simply to use the three filters that closest approximate the human visual peaks - 600, 530 and 480 nm, for Red, Green and Blue - and slap them together with Ye Olde Photoshop (or in my case, Perl) to make a full-color image. This produces very satisfying images. Check it out!

However, this method has a flaw: the human visual system is additive, meaning that single-wavelengths don’t give the whole picture - each color opsin in your eye is stimulated by the whole spectrum, meaning that what you see as “red” might actually be an amalagam of two individually non-red peaks.^*

Unfortunately, we don’t have data from the whole spectrum available to us - we only have eight wavelengths, six of them in the visual range. PANCAM takes this data and fits a third-order polynomial to it to generate an approximation of the true spectrum. This spectral data is then converted into the XYZ color space (a standard color space) by convolving it with the XYZ standard observer functions that (more or less) define the primary colors of that space.^† Those XYZ values are then mapped to the familiar sRGB space and slapped together to produce a “true color” image. The result, side by side with the “naive” method:

Egad! There’s a world of difference there. So who’s got it right? Hard to tell… unfortunately PANCAM doesn’t have any pictures of the color calibration target that sits on top of the rovers posted in their collection of true color images, so it’s difficult to be sure. However, the average spectra values in the data for the above image for the sky (blue line) vs. the ground (red line) look like so:

This seems to suggest there’s something off about the PANCAM results - the sky should be white-tending-to-blue, and the ground should be red. Of course, it’s possible our visual system is so heavily red-skewed that we’d still see the spectrum on the left as reddish, but I’m inclined to disbelieve it could see the deep, dusty red shown in the PANCAM image. It seems more likely the reconstruction method is flawed somewhere. Furthermore, the naive method should be pretty good at telling us the color of the sky, since the sky color is composed of all wavelengths in varying intensities (which may not be true of rocks on the ground, meaning those colors are more likely to be wrong in the naive method). I’m staying aboard this conspiracy ship!

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^* Leading me to wonder if we will, one day, encounter a fully spectrographic visual system - one that sees spectra instead of colors. You’d recognize the chemical composition of everything!

^† Sloth prevents me from recapitulating their method - all the necessary data is linked from here, if you feel inclined to do it for yourself.

Some of you may already be familiar with Earth Hour, an effort pioneered by the Australians to increase awareness about global warming by symbolically turning off all lights in participating major cities around the world for one hour. It occurs on April 1 (already a great day, now even better) of each year, going since 2007.

When I heard about this my first thought was - “Holy shit! Dark sky!” After all, who gives a toss about stopping catastrophic climate change when there’s the possibility of seeing a really spectacular starry sky? As I’ve hinted here before, I’m more or less committed to sidereal worship, and it’s long been a fantasy of mine to become Lord Commander of Earth so that I can impose just such a venture (viz., forced blackouts) on major cities. I mean, check out the pathetic Bortle Scale map of North America. A guy like me hasn’t a chance in this country.

Or so I thought! But, cloaked in the guise of “environmentalism”, I can advance my umbratory agenda. It seems that Chicago is already on board, and certain other cities seem like ripe targets to follow. If things continue in this vein, I may even abandon my plans to sabotage certain transformers on Walpurgis Night.

One of my all-time favorites.

I got my PhD!

That is all.

This is a real picture! Of an actual place! Someday, when I am a real boy, I will go there.

Some of you may have seen the news that a large amount of water ice has been discovered hidden under Mars’ south pole. Supposedly this is enough to cover the entire surface of Mars to a depth of 10m. Pretty cool!

Of course this doesn’t make much sense, since water falls to the lowest point it can, so it’s reasonable to ask what Mars would look like if all this water flowed down to fill basins. I did a pretty naive approximation of this, the results of which are below.

First we start with a topography map of Mars, courtesy NASA:

This is an equirectangular projection, which makes math easy on us. Given the surface area of Mars, we know how much water is sitting around (in cubic meters) based on the above figure. If we assume that this could all sit on top of the dry Martian surface without it being sucked up like a sponge (doubtful), we can work out what height this would fill merely by subtracting away the terrain. This works out to a height of 90m, surprisingly enough. Mars seems to be pretty flat. So we can flood everything below that:

Then some false coloring and completely fictitious clouds for jazz:

Looks neat! I’d live there.

Many moons ago, when YouTube was still young and green, one of my favorite video posters was a guy named MadV, a dude in a Guy Fawkes mask who posted short videos consisting of simple but stunning illusions. After producing five or six such videos, he announced his retirement and skived off to lands unknown and distant. Recently he returned with a pair of videos - the first an invitation, and the second the compendium of the 2,250 responses he received. I was moved.

One World:

The message:

Hooray.

Lately I’ve been playing a lot of video games. Actually, I’ve been playing a lot of video game: Halo 2, the $600 million-selling sequel to Halo: Combat Evolved. Halo is a sprawling space epic (or at least it tries to be - the format of first-person shooter is obviously somewhat restrictive). This is my first encounter with Bungie Software, which it seems has a long history of intricate games with detailed backstories and overstuffed plots. I can’t say it’s particularly inventive, since Halo is an agglomeration of hundreds of ideas pilfered from some of science fiction’s best writers.^* But there’s neat work in that assemblage itself, which I think earns it a place in the annals of worthy science fiction.

This leads me to ruminate on the central appeal of all good (non-dystopian) science fiction, which I think boils down to “narrative”. Not the internal narrative of, e.g., the Halo trilogy, which is compelling in its own right, but the implied, grand narrative for human history. The idea that we have some kind of future at all that doesn’t suck. Or rather, that’s still tense and full of conflict and purpose, that offers new vistas and directions.

Hungering for this sort of narrative is arguably a pretty juvenile impulse, one which might prompt more sober individuals to tell you to “grow up”, and possibly to “get a job”. But I’ve never been afraid of juvenile impulses; I’m probably dangerously attracted to them.^† In this instance, I think the impulse has extraordinary merit.

True, we’re hardly in a position to be thinking about such things. It’s absurd to even conceive of historical trajectories for humanity when we’re parching the ground beneath our feet, and the majority of humanity refuses to acknowledge the humanity of the rest of humanity. But you’re never going to cure myopia by staring at the end of your nose. Grand ideas are what’s needed, to draw the gazes of us ants away from the dirt and towards the sky. Where, after all, we want to end up, right? We don’t want to stay in the dirt.

The grander, the better; preferably, they should be so massive they have their own gravity. So that, even while we’re distracted by the idiocy of our lives - our nationalities, our property, our families, our jobs - the individual vectors of our trajectories will tend towards a single direction, and, eventually, hopefully, form a tide.

I realize this is somewhat of a discredited notion, and we’re supposed to be living in the end of history where nothing at all happens except possibly the purchase of a new pair of Manolo Blahniks, but I’m tired of postmodernism shitting on the mere idea of imagination. We NEED to imagine something, even if it’s false, unattainable, or hopelessly stupid. If we don’t imagine something, we’re listless and boring. (You may have observed this in your own life. When you cannot imagine your own future, you become unspeakably dull.)

All of which is to bring me around to my fucking point, which is: where do you think we’re going? Where do you want us to end up?

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^* It piqued my interest at first because it’s set on a ringworld (the eponymous “Halo”), first conceived by Larry Niven in the book of the same name.

^† As Lao Tse said, “I don’t grow up, I throw up. And when I look at you, I shut up.” Insofar as “growing up” means calcification and death, it should be avoided.

Do wolves have religion? When they congregate under the light of the moon, is it for midnight mass? When they send their howls up into the clear, dark sky, are they singing ancient hymns, passed down from one generation to the next?

        "Hail, silver goddess, on your circuit of the sky.
                We make ourselves your supplicants.
       Bless us, o goddess,
                that we may carry your pale light in our eyes."

When dogs howl at the moon, is it memory that provokes them?

        "Hail, pale one! We have not forgotten.
                Though our ways have changed, our hearts, our eyes,
        Our voices belong to you alone."

Or do only humans contemplate mystery, and feel the movement of stars and the tug of the breeze in the depths of their being?

Howl at the moon tonight.