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Curiosity's Latest High-Res Photo Looks Like Earth
New submitter bbianca127 writes "Curiosity sent a picture down to us, and it looks a lot like Earth. Actually, the picture's color quality has been changed — to human eyes, the landscape would look a lot more reddish. Still, it looks remarkably like the southwestern United States (bringing to mind the Arrested Development quote about how Lucille Bluth would rather be dead in California than alive in Arizona)." Definitely a different sense of the place than the one given by the reddish-brown posters I remember from elementary school.
Especially the part that mentions where the photo is from.
"bringing to mind the Arrested Development quote about how Lucille Bluth would rather be dead in California than alive in Arizona"
no, actually, sorry, not at all
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
How much more do we need before the public accepts that it's just a few guys driving around Nevada?
Why is it that people keep redirecting me to a third party site to see the rover images, in stead of linking to the Nasa source?
That's because that photo is the white-balanced version! A white-balanced photo is what the scene in Mars would look like if you literally took the scene, cut out that whole area of ground, transported it to Earth and viewed it under the Earth's sky.
Big apple, new Yorik, undig it, something's unrotting in Edenmark.
While there may be a few color differences, one iron and silicate planet is likely to look much like another when there is no vegetation covering.
Official Heretic from the "Church of Global Warming". Proven right thanks to whistle blowers. AGW = Flat Earth Theory
Here is a page on the MSL's site where you can see both versions of the photo:
http://mars.jpl.nasa.gov/msl/multimedia/images/?ImageID=4431
One is white-balanced and one colored. The white-balanced version represents what the scene would look like to human eyes under an Earth sky. The colored represents what the scene would look like to human eyes on Mars.
The point of using white-balanced photos is that geologists are used to looking at rocks on Earth. So when a geologist wants to judge rock characteristics using color, it helps to white-balance it so the color is similar to what it would be if looking at those rocks on Earth.
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Big apple, new Yorik, undig it, something's unrotting in Edenmark.
Yyyyeah...they're not "altering" the photo. What they're doing is balancing the color so that people can know what they are seeing. The reason for this is that the Martian atmosphere has radically different color properties from that of our own. What this means is that visible observations cannot be made reliably: for example, a red rock on mars may not actually be red as we understand the color, and so conclusions geoloists make based on a color may be erroneous, because they are basing those conclusions on colors observed under earth's sky.
If anyone's interested, another scene is shown with and without white balance here: http://apod.nasa.gov/apod/ap120815.html
Not really...
If you don't mind being unable to take color shots of relatively fast moving things, you can use a conventional greyscale sensor, swap color filters between frames, and then crunch the result into a color image(or, if you have the space and don't mind a moderately complex optics package, you can have three greyscale sensors, each with a fixed color filter). If you need a color image within one frame, you use a fixed bayer(or similar) filter and demosaicing. Eats nontrivial resolution compared to the pure greyscale or swapped filters strategy; but you get everything in one shot and fewer moving parts. Then you have the somewhat oddball Foveon approach, where your greyscale sensors are stacked vertically, and use the different rates of absorption in silicon of different frequencies to do the filtering...
In very broad terms, they all have the 'greyscale sensors and filters' strategy; but there are a fair few ways to go about it. If you count chemical and biological sensors, you are more likely to find sensor elements that are actually tuned to a specific wavelength, rather than filtered to it; but the final image is still a matter of crunching together results from individual elements that are really only giving you intensity data for a relatively narrow slice of frequencies.
From the article:
> The colors in this image are not what a human standing on Mars would see — the presence of dust in the atmosphere would make the scene appear much redder. Instead, the pictures have been white-balanced to show how it would appear under typical Earth lighting conditions.
So the story is that a photo of Mars that has been adjusted so it looks like Earth to make it easier for geologists to interpret... looks like Earth. Wow.
Gosh, some guy on Slashdot wants to move on. Hey, everybody! Stop testing the MSL! Forget all the calibration tests. Drop the checkout sequences. No need to make sure anything is working right. This guy said go. Just apply all available current to all the wheels. No, there's no time to make a traversability map. All power to the forward shields! Damn the torpedos! Full speed ahead!
Obviously this must mean that Martian rocks and Earth rocks share a common ancestor!
Yes. It does. That common ancestor is called the protoplanetary disc which led to the formation of the inner solar system.
Now go troll somewhere else.
Entia non sunt multiplicanda praeter necessitatem.
When the spectrum of ambient light does not match that of "white" light (which is simply the particular spectrum we evolved to perceive), the eye's photoreceptors become disproportionately fatigued, and perception of the light's color drifts toward white. You can experience this phenomenon yourself if you light a room entirely with red party lights. Soon, your red photoreceptors will become fatigued and the colors of objects in the room begin to appear more normal. I think explorers on Mars would experience the same effect. So photos like this are actually how it would look to them.