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Bad Astronomy
« Chiropractors bend over backwards to screw up
Tat two »

The artwork of the Martian landscape

It’s been a while since I’ve sung the praises of the Mars Reconnaissance Orbiter’s HiRISE camera, which takes incredibly hi-res images of the surface of Mars. Thanks to the HiRISE Twitter feed, I found this incredible picture:


Can I get a Holy Haleakala! from the congregation?

Wow. I mean seriously, wow. You really really want to go look at the embiggened version. What you’re seeing here are sand dunes on Mars. This region is in the center of a large crater at mid-north latitude on Mars, a couple of hours past local noon, and with a resolution of 50 cm (18 inches) per pixel. Sand dunes are common in crater beds, where the wind can blow steadily across the surface and sculpt the ever-present sand into those flowing sculptures.

But what this picture so spectacular are the graceful blue-gray swirls arcing across the dunes. These are caused by dust devils, which are a bit like mini-tornadoes. If the ground gets heated, rising air can punch through cooler air above it. This starts up a convection cell, with warm air rising and cool air sinking. If there is a horizontal wind the cell can start spinning, creating a vortex like a dust devil. I’ve seen hundreds of these on Earth, and they are wonderful and mesmerizing to watch.

The important thing to note here is that the sand in the craters of Mars is actually dark grey in color, since it’s made of basalt. The reason it looks red in pictures is because covering the sand is a thin layer of much finer dust, and the dust is what’s red. When a dust devil moves over the Martian surface, it can pick up the very light dust particles, but not the heavier sand grains. So those blue-grey swirls are tracks where the dust devil has vacuumed up the dust, revealing the darker sand underneath. If you look carefully in the tracks, you can see the sand dune ripples are undisturbed. Only the dust is gone.

There’s more to see in the picture as well. There is a sloping dune peak cutting across from top left to lower right (it’s more obvious in the larger context view of this region), and again more dark streaks, linear this time, probably caused by sand sliding down the dune face. When the sand moves, the dust covering it gets disturbed and once again you see the darker color of the sand itself. I also love the way the dune shapes change depending on where they are in the picture, caused by differences in the wind patterns across the floor of the crater.

When I look at pictures like this, I am smacked in the face with the cold, hard fact that Mars is a world. It’s not just a dot in the sky, it’s not just a set in a movie, it’s not just pictures from a space probe. It’s a planet, a vast complex system of interacting environments which produces climates, landscapes, vistas, weather.

And man oh man, does it produce beauty, awe, and wonder. Wow.

My thanks to Dr. Alfred McEwen of HiRISE for taking the time to explain to me the difference in color between the dust and the sand, and how that affects this image.

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October 15th, 2009 11:28 AM by Phil Plait in Astronomy, Cool stuff, Pretty pictures | 80 comments | RSS feed | Trackback >

80 Responses to “The artwork of the Martian landscape”

  1. 1.   Stacy Says:
    October 15th, 2009 at 1:08 pm

    The sloping dune peak looks like a bar code.

  2. 2.   Lee Says:
    October 15th, 2009 at 1:13 pm

    I thought this was the reveal of your tattoo. Looked (on my BB) like skin and tattoo ink and the top left like the top of your, um, bum. Very happy to be wrong!

  3. 3.   Rob T. Says:
    October 15th, 2009 at 1:13 pm

    This should have been your tattoo’s design.

  4. 4.   Crux Australis Says:
    October 15th, 2009 at 1:14 pm

    That *actually* looks like the inferior aspect of a pair of tattooed breasts.

  5. 5.   Disclaimer Says:
    October 15th, 2009 at 1:14 pm

    “But what MAKES this picture so spectacular…”?

    And, yes, wow. I mean seriously, wow!

  6. 6.   Yoweigh Says:
    October 15th, 2009 at 1:16 pm

    The dark streaks look a lot like the shadows of plant life to me, but of course that’s only because my brain can’t comprehend the scale.

    @Crux: So the blue streak is some deep cleavage or something? :)

  7. 7.   Paul M Says:
    October 15th, 2009 at 1:18 pm

    At first glance, I thought you were showing off your new tattoo.

  8. 8.   FLAnatic Says:
    October 15th, 2009 at 1:18 pm

    I think those are sandworm tracks…where’s the spice?

  9. 9.   Yoweigh Says:
    October 15th, 2009 at 1:25 pm

    FLAnatic wins the thread.

  10. 10.   Kevin Says:
    October 15th, 2009 at 1:33 pm

    Wow. This is now my desktop background at work.

  11. 11.   Larian LeQuella Says:
    October 15th, 2009 at 1:37 pm

    You have a Holy Haleakala! and more from this member of the congregation!

    And I’ll just echo the tattoo comments.

  12. 12.   Dee Says:
    October 15th, 2009 at 1:40 pm

    Is there something in the photo that looks like a stretched out UPC code ribbon? A reflection or something?

  13. 13.   Efogoto Says:
    October 15th, 2009 at 1:47 pm

    The pattern of the dunes put me in mind of the loops and whorls of a fingerprint. Pareidolia, but fun.

  14. 14.   Alec Says:
    October 15th, 2009 at 1:56 pm

    Is this the first conclusive evidence of major cleavage on Mars?

  15. 15.   Todd W. Says:
    October 15th, 2009 at 2:06 pm

    This is clearly a shadow cast by his holy noodliness, the Flying Spaghetti Monster. All praise his noodly appendage. Ramen.

  16. 16.   porlob Says:
    October 15th, 2009 at 2:07 pm

    Wow. Gorgeous.

    Just a few minutes ago, I thought to myself, “you know, I really need a new desktop background. I wonder if the Bad Astronomer can provide.” Clickity click, “AWESOME!”

    The downside is that out of the corner of an eye (like, say, the dozens of people walking past my desk), it looks a tad bit like a super-zoomed naked body… Which I suppose it is, just not a HUMAN body.

  17. 17.   Mike Torr Says:
    October 15th, 2009 at 2:09 pm

    Can’t even think of anything to say. There’s really nothing TO say after seeing that, except that I’m so glad to be alive.

  18. 18.   Thomas Siefert Says:
    October 15th, 2009 at 2:09 pm

    Ditto the tattoo and cleavage comments, you might want to notify Richard Wiseman so that he can do his poll thing on this.

  19. 19.   Richard Bell Says:
    October 15th, 2009 at 2:20 pm

    This image reminds me of sketches of Mars by 19th century observers like Giovanni Schiaparelli or Eugene Antoniadi.

  20. 20.   Julie Says:
    October 15th, 2009 at 2:21 pm

    It looks more than a little bit like some of the old drawings of the infamous Martian canals to me. I don’t suppose anything of those whorls would be large enough to be seen from Earth, but that’s what it brings to mind to me.

  21. 21.   The Artwork of the Martian surface - Science Fiction Fantasy Chronicles: forums Says:
    October 15th, 2009 at 2:34 pm

    [...] Artwork of the Martian surface The artwork of the Martian landscape | Bad Astronomy | Discover Magazine What an [...]

  22. 22.   Mike Says:
    October 15th, 2009 at 2:37 pm

    What the hell, man. I thought this was an anti-anti-vax blog, what’s all this astronomy crap?! That’s it, I’m leaving.
    ;)

  23. 23.   Geen normale Marsfoto meer, dit is gewoon Kunst | Astroblogs Says:
    October 15th, 2009 at 2:43 pm

    [...] We wisten al dat de HiRISE camera aan boord van de Mars Reconnaissance Orbiter (MRO) prachtige plaatjes kan schieten, maar dat ‘ie in staat is om een juweeltje als bovenstaande foto te maken grenst echt aan het ongelofelijke. Dit is geen foto meer, dit is gewoon Kunst. Kunst met een grote K dus. Op 24 augustus 2009 nam de HIRISE deze foto van een duingebied op Mars, ergens middenin een krater halverwege het noordelijk halfrond (26,7° NB en 62,8° OL). De resolutie is 50 cm per pixel (dit is de grote versie). Wat opvalt zijn uiteraard die grijze krullen, die de indruk wekken dat je kijkt tegen tatoeages op een menselijk lichaam. Het zijn echter ‘kale’ plekken in het landschap, die ontstaan zijn door stofhozen. De krater is eigenlijk bedekt met een grijze laag zand, gemaakt van bazalt. Maar dat zandlaagje is op haar beurt weer bedekt met een rode stoflaag. Komt er zo’n stofhoos langs, een bekend verschijnsel op Mars, dan neemt die als een stofzuiger het stof mee en daardoor komt de grijze zandlaag bloot te liggen. Het zand zelf is te zwaar om meegenomen te worden met de hoos. Verder zie je op de foto van linksboven naar rechtsonder een blauwwitte sluier, met parallel lopende grijze strepen. Die sluier blijkt de ‘kam’ te zijn van de duinen, die op deze grotere foto beter te zien zijn. De grijze strepen zijn waarschijnlijk het gevolg van zand dat de helling van de duinen afglijdt. Wie nog steeds niet kan geloven dat de foto ècht van Mars is moet deze HIRISE-pagina maar bekijken. Wie/wat doet HIRISE dit na? Bron: Bad Astronomy. [...]

  24. 24.   ttrygve Says:
    October 15th, 2009 at 3:06 pm

    Speaking of tattoos, when are we going to get the big reveal?!

  25. 25.   Christina Viering Says:
    October 15th, 2009 at 3:10 pm

    I was thinking the same thing everyone else was-looks like a tat! But it would make a great wallpaper, too!

  26. 26.   MichaelL Says:
    October 15th, 2009 at 3:13 pm

    This reminds me of the paintings of what were once thought to be ‘canals’ on Mars. Very cool!

  27. 27.   Donnageddon Says:
    October 15th, 2009 at 3:18 pm

    Beautiful, but I still don’t quite understand what that blue-ish “mist” is?

  28. 28.   becky'sthoughts Says:
    October 15th, 2009 at 3:18 pm

    @FLAnatic: You are awesome!!

  29. 29.   Brock Says:
    October 15th, 2009 at 3:20 pm

    When I look at pictures like this, I am smacked in the face with the cold, hard fact that Mars is a world. It’s not just a dot in the sky, it’s not just a set in a movie, it’s not just pictures from a space probe. It’s a planet, a vast complex system of interacting environments which produces climates, landscapes, vistas, weather.

    Beautiful words to accompany a gorgeous image.

    I once took an intro course in planetary geology (so I’d know Valles Marineris, Hellas Planitia, or maybe Alba Patera if i saw them), but I still had no idea what this was. Thanks for the lesson! Amazing.

  30. 30.   KC Says:
    October 15th, 2009 at 3:33 pm

    WTF???

    Someone is definitely channeling Percival Lowell and Schiaparelli!

  31. 31.   Rory Kent Says:
    October 15th, 2009 at 3:34 pm

    Can I see a Spice harvester at the top right?

    But seriously, that is SPECTACULAR! Really makes you think about how special our planet is. Mars is so similar, yet so uninhabitable.

  32. 32.   CllockworkRobot Says:
    October 15th, 2009 at 3:37 pm

    Erotca from Mars!
    I like it.

  33. 33.   Spencer Attridge Says:
    October 15th, 2009 at 4:00 pm

    eeek my mind can’t comprehend the scale of it.. ditto this equates my wallpaper now and that I am glad to be alive to see it.

  34. 34.   Kristin C Says:
    October 15th, 2009 at 4:52 pm

    My jaw dropped, for reals.

  35. 35.   JoeSmithCA Says:
    October 15th, 2009 at 5:42 pm

    At first I was going to say, “Ok Phil is playing a prank on us and showing us a really funky tatoo on a woman”. My wife thought the same. Funny thing is that even after showing her the full image, she said “Ewwwww a parasite!”

    No, that’s Mars silly!

    Very cool, thanks for sharing Phil!

  36. 36.   Charles Says:
    October 15th, 2009 at 5:44 pm

    @Lee #2: I also thought for a moment that it was a tattoo, albeit one done by a drunkard. And that fold of skin at the top does look very bum-like.

  37. 37.   Dennis Says:
    October 15th, 2009 at 5:45 pm

    Must. Go. There. NOWWWWW!!! (I’m holding my breath until we do.)

  38. 38.   Molly Says:
    October 15th, 2009 at 5:45 pm

    Sorry. I can’t make sense of this picture. It looks like a closeup of a weedy garden, and the diagonal blue thing looks like a double exposure. Are you sure this is Mars?

  39. 39.   Patti Says:
    October 15th, 2009 at 6:09 pm

    Seriously, guys, I don’t see what you see. I see what looks like a reflection of water on the right side, worms (like tapeworm, roundworm, etc.), two sets of DNA or one long barcode with an X at the left end, an upside down foot, and a crying eye. I wish I could get a bigger screen shot.

  40. 40.   Brango Says:
    October 15th, 2009 at 6:10 pm

    So, every painting requires a painter, eh.

    Maybe we should ask Ray Comfort who painted this.

  41. 41.   Patti Says:
    October 15th, 2009 at 6:16 pm

    It looks like a beautiful work of art to me (surrealist: Chagall or Dali are two that remind me of this look.)

  42. 42.   Markle Says:
    October 15th, 2009 at 6:54 pm

    Its like the inverse of the pressed blueberries in Gusev. But writ really large. Cool.

  43. 43.   fred edison Says:
    October 15th, 2009 at 7:08 pm

    Whoa! Truly an amazing and beautiful shot of a dynamic and different world.

  44. 44.   Owen Says:
    October 15th, 2009 at 8:02 pm

    Holy frikkin’ wow. That is just unbelievably cool. How much is a ticket to get there? Oh wait…

    Someone should really get this as a tattoo…

  45. 45.   kuhnigget Says:
    October 15th, 2009 at 8:06 pm

    How much is a ticket to get there?

    About 1500 times less than the price of waging war against Iraq.

  46. 46.   Just me Says:
    October 15th, 2009 at 9:08 pm

    WOW. Incredible! I never cease to be amazed at all the cool things we can do, all the astounding things we’ve been able to discover and the discoveries yet to come. I wish I could live a few hundred generations so that I could see where our journey takes us.

    Um. Okay. It doesn’t make a whole lot of sense to be amazed at discoveries yet to come, but I didn’t get much sleep last night.

  47. 47.   Jason Wehmhoener: Says:
    October 15th, 2009 at 10:24 pm

    [...] (via Bad Astronomy – The artwork of Martian landscape) [...]

  48. 48.   Daltana Says:
    October 15th, 2009 at 11:58 pm

    There are certain aspects of this picture that could possibly be used for an ad for Victoria’s Secret.

  49. 49.   Annie Morris Says:
    October 16th, 2009 at 12:19 am

    Stunning. Can’t.Speak.

    Too.Much.Awesome.

  50. 50.   Pacific Tides » Marsian Art Says:
    October 16th, 2009 at 12:32 am

    [...] found this via the always great Bad Astronomy [...]

  51. 51.   Doug Watts Says:
    October 16th, 2009 at 1:17 am

    Mars, a beautiful place, and utterly and completely dead.

    And we are destroying the only known living planet with breakneck speed.

    Cognitive dissonance, people.

  52. 52.   Ausduck Says:
    October 16th, 2009 at 2:19 am

    *gobsmacked*
    seriously, Phil this is way cool! I sent the picture to my 14 yo twin nephews who could not believe it and think they have a really cool awesome auntie. :)
    And of course, the really cool awesome BA has two new fans :D

  53. 53.   Buzz Parsec Says:
    October 16th, 2009 at 2:32 am

    I agree with all the tattoo comments. I just hope Richard Hoagland doesn’t find out about this!

  54. 54.   Nigel Depledge Says:
    October 16th, 2009 at 3:42 am

    Wow!

    Well done, HiRise!

    Spectacular image. Thanks, indeed, BA, for drawing this to our attention!

  55. 55.   Ron Harris Says:
    October 16th, 2009 at 4:58 am

    Nice cleavage!

  56. 56.   Lars Says:
    October 16th, 2009 at 5:08 am

    That picture reminds me of the chest of the waitress at the local metal rock pub. She’s got some sweet tats.

    @kuhnigget: To a layman like me, your calculations seem highly plausible. Hadn’t it been for the Dune reference earlier in this thread, I’d declare it a w00tz0r.

  57. 57.   Mike Says:
    October 16th, 2009 at 5:11 am

    KC Says:
    Someone is definitely channeling Percival Lowell and Schiaparelli!

    My thoughts exactly!

  58. 58.   Astronomynut Says:
    October 16th, 2009 at 5:39 am

    Who else sees a lake at top of the bottom fourth of the full size image? Just below the dark band. I’d be interested to hear what that is. I know it’s not, but it sure looks like a giant lake.

  59. 59.   What is it? Says:
    October 16th, 2009 at 6:10 am

    [...] [...]

  60. 60.   Luke Dudney Says:
    October 16th, 2009 at 7:13 am

    Instant desktop wallpaper.

  61. 61.   Grizzly Says:
    October 16th, 2009 at 8:39 am

    The blue stripe is actually a downslope. Consider that it is a couple of hours past noon. Light coming from the left, the blue is illuminated from there.

  62. 62.   El arte en el paisaje marciano « Pasa la vida Says:
    October 16th, 2009 at 9:05 am

    [...] Vía Bad Astronomy [...]

  63. 63.   Shawn Says:
    October 16th, 2009 at 1:04 pm

    Holy Haleakala.

  64. 64.   The artwork of the Martian landscape « Xenophilia (True Strange Stuff) Says:
    October 16th, 2009 at 4:13 pm

    [...] via The artwork of the Martian landscape | Bad Astronomy | Discover Magazine. [...]

  65. 65.   Chas Becht (mrchas) 's status on Saturday, 17-Oct-09 03:32:00 UTC - Identi.ca Says:
    October 16th, 2009 at 9:32 pm

    [...] http://blogs.discovermagazine.com/badastronomy/2009/10/15/martian-swirly/ a few seconds ago from Gwibber [...]

  66. 66.   Kristjan Says:
    October 17th, 2009 at 11:43 am

    This revelation would suggest that the so called “wet patches” on the sides of some hills on Mars are not water seepage, but in fact dry landslides that simply are exposing the darker soil underneath.

  67. 67.   Drawings on Mars? « My Dark Sky Says:
    October 17th, 2009 at 4:08 pm

    [...] Bad Astronomer will explain to you how this landscape was done. [...]

  68. 68.   FlowersInHisHair Says:
    October 17th, 2009 at 5:24 pm

    I see these swirls and I think: good candidate for geek-tattoo.

  69. 69.   Bahdum (aka Richard) Says:
    October 17th, 2009 at 8:28 pm

    I saw a documentary show on TV one time talking about super weather, or something along those lines. Anyway, they brought up the Martian dust devils. However, they likened them to tornadoes, rather than “dust devils.”

    I think it was sensationalism in action, really.

    In the Central Valley of California, I have noticed an area that has its fair share of dust devils. They range from less than a foot in diameter to maybe four to six feet. (I’m bad at judging distance and eyeballing measurements, so take that with a teaspoon of salt.)

    They can be wispy and weak and they can be bold enough to garner shading on themselves. Even from miles away, you can make some out.

    But, I’m driving when I see them so I can only give them the briefest of attention.

    They are mesmerizing, though.

  70. 70.   Carnival of Space 125 | Orbiting Frog Says:
    October 18th, 2009 at 10:27 am

    [...] on Bad Astronomy, Phil has some imagery from Mars that you need to embiggen fully to enjoy. Martian landscape [...]

  71. 71.   Luiz Felipe Vasques Says:
    October 18th, 2009 at 5:38 pm

    > 50 cm (18 inches)

    I’m sorry, but it isn’t accurate enough. An inch is roughly 2,5 cm. So, making it double and suming up the half of the inch valor, we would have 45 cm.

    Just for being nitpicky, sorry.

  72. 72.   Mike Pietrzak Says:
    October 19th, 2009 at 11:04 am

    Umm… air on Mars? that’s interesting.

  73. 73.   Blake Says:
    October 19th, 2009 at 11:56 pm

    That image looks “upside down”

    Very cool!

  74. 74.   Trazas de remolinos de polvo marcianos | Imagen astronomía diaria - Observatorio Says:
    October 21st, 2009 at 12:01 am

    [...] tan solo unos pocos minutos de duración, los remolinos de polvo se hacen visibles a medida que aspiran polvo rojizo suelto, dejando la arena más oscura y pesada [...]

  75. 75.   hubs Says:
    October 21st, 2009 at 5:22 pm

    @Mike Pietrzak Martian air is mostly carbon dioxide, there is very little oxygen in it.

  76. 76.   Primordial Ooze : Dust Devils on Mars Says:
    October 22nd, 2009 at 5:15 am

    [...] are also common in dry and desert areas on planet Earth. Typically lasting only a few minutes, dust devils becoming visible as they pick up loose red-colored dust leaving the darker and heavier sand beneath [...]

  77. 77.   Further Adventures in Procrastination « The Casual Art of Procrastination Says:
    October 23rd, 2009 at 10:15 am

    [...] # Artwork from Mars [...]

  78. 78.   eternal Says:
    November 24th, 2009 at 12:08 am

    damn this picture looks soooooo dirty, it looks like the freaking Y…

  79. 79.   The Mad LOLScientist, FCD Says:
    December 12th, 2009 at 10:34 am

    HOLY HALEAKALA! AAAAAAAAYYYY-MEN!

  80. 80.   algeria: Says:
    February 26th, 2011 at 1:41 pm

    can someone tell me wat is this??… :D :P

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