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First Pictures From Mars Phoenix Lander
Now that the solar panels have been deployed, the Mars Phoenix Lander has begun sending back pictures of the red planet to the hungry space geeks of earth. In just a few weeks the claw will deploy and they'll start digging a hole. The scientists expect to use the dirt to construct a little sand castle which they will defend with several GI Joe action figures, and a bald barbie stolen from their sisters. Oh, and maybe find water or bacteria.
It's more scientifically useful to put a really good black & white camera onboard, and then include some filters, than to put a color camera.
IIRC, pretty much all the color images from previous landers are composites of multiple images with different filters, making a human-eye approximation.
Have you been touched by his noodly appendage?
Here. The blue ellipse was the intended landing zone, the red the actual, and the green box was... umm... a Martian football field? I dunno.
Have you been touched by his noodly appendage?
No, just that black & white sensors give better detail. They've got a set filters that will allow them to make pretty coloured pictures.
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Community forum for Google Earth - Mars section: http://bbs.keyhole.com/ubb/postlist.php/Cat/0/Board/mars
It's probably either the heat shield or the chute --Ivan
I think it's called regolith.
Google cache ftw. im reading now, shall post my reply in a few.
When an object is too bright for a CCD camera, it causes excess charge to "bloom" into adjacent pixels. It's a common artifact.
There's a map at the bottom showing Phoenix's position relative to the other landers.
Not sure if it's on the NASA site?
http://www.jpl.nasa.gov/news/phoenix/images-all.php
That seems to have just about everything, plus some earth comparisons that should give you an idea of where on Mars it landed.
Because with that particular camera, taking an RGB photo involves making three separate exposures with different filters, transmitting the result back to Earth, and combining them. Given that the lander has been on the ground for less than 24 hours so far, they're still at the quick-glance-around-to-see-where-we-are stage and don't want to waste bandwidth taking the same picture three times. Give them time. Given the PR value of RGB images I'd expect some to start showing up within a few days.
(In fact a two-colour image has shown up already, but it's not true RGB and probably isn't what you're looking for.)
Do you know how your spare Canon camera works...? You guessed it, by having a monochrome sensor with appropriate filters in front of certain elements. The cameras on the lander will no doubt out-perform your canon in terms of sensor quality, lens quality, focal range, etc. The only advantage the Canon might have is in the number of megapixels.
When our name is on the back of your car, we're behind you all the way!
Situated atop an extended mast, SSI will provide images at a height two meters above the ground, roughly the height of a tall person. SSI simulates the human eye with its two optical lens system that will give three-dimensional views of the arctic plains. The instrument will also simulate the resolution of human eyesight using a charged-coupled device that produces high density 1024 x 1024 pixel images. But SSI exceeds the capabilities of the human eye by using optical and infrared filters, allowing multispectral imaging at 12 wavelengths of geological interest and atmospheric interest.
My Nikon D50 captures some of the UV and IR as well. That's the other reason everyone uses a UV filter on their lenses (the first being, it's a cheap way to protect the camera lens that might well be worth more than the camera). With a special filter, I can take IR pictures with my Nikon. Even your eyes pick up a bit of the UV -- if you look at a blacklight bulb, it's hard to focus on -- the lenses in your eyes focus visible light and don't do as good a job on the UV.
This sig seemed like a good idea at the time....
Your Canon digital is a black and white camera with filters that make approximate color images.
Now if you'll excuse me, I have to go back to photoshop to make the photograph of a color chart come out close to the same on the screen as it looks in real life. Then there's the real fun -- getting the thing to print out so that it's close to the chart and the computer screen.
There are times when I'm about ready to switch to all black-and-white.
This sig seemed like a good idea at the time....
As far as space missions and human-friendly color images, the bottom line is that transmission of images is expensive. Thus, they don't use the human-friendly wavelengths very often. However, there are various mathematical ways to approximate such using the other filters plus some sample calibrations, and this is usually what we see in press-release images from most missions.
For example, the rover missions usually use infrared filters instead of "red" filters for that end of their range; but they can use that one to approximate the red filter with some adjustments.
I suspect they will do similar things with this mission once it gets up to speed. The preliminary color images are 2-filter approximations. If they do what the rovers did, they'll use 3 filters that don't match human eyesight but compensate with digital processing to give us "human" approximations. They'll be better than these early 2-filter approximations.
If you as a human are upset at this approximation; fish, birds and reptiles will be even more angry because they have 4 color cones instead of 3. (We'd probably have four if our mammalian ancestors were not nocturnal. Damned those mammal-squishing dinosaurs who made us hide in the darkness! I wish meteors on you for limiting our color!)
Table-ized A.I.
http://www.nasawatch.com/archives/2008/05/deja_vu_on_mars.html I had a rather strange case of deja vu tonight as the first images from Phoenix flashed on my computer screen. The image on the left was taken on 25 May 2008 on Mars at 68 deg North. I took the picture on the right on Devon Island, 75 deg North in July 2007. I'm just saying
Apparently they were able to image the thing from orbit while on its way down on the chute:
http://www.nasa.gov/mission_pages/phoenix/main/index.html
They mentioned giving it a try at a press conference, but gave it really small odds because the image size is much smaller than the potential landing range drift. Lucky hit.
Table-ized A.I.
No. Soil processes vary *enormously*. This one is likely a type of gelisol in a pretty exotic environment, and in the pictures there are obvious indications of "patterned ground" which (everybody hopes) is due to ice below the surface.
If you think there isn't anything technical about dirt, well, it means you have about as much knowledge of soil science as a computer newbie has about assembler. That's okay, but don't assume that because it looks ordinary it actually is ordinary to someone knowledgeable.
CCDs are only one kind of imaging technology. It's not necessarily the best, there are trade-offs. The other major type is CMOS, which has several sub-types and variations.
The rovers Pathfinder, Spirit and Opportunity use a lot of different color filters that are placed in front of the imaging sensor. Because the filters are fixed, 3 CCD, or 3 CMOS cameras isn't very good for science, it's good for making a pretty picture.
Digital imaging equipment doesn't see the world in colour. In a digital camera light causes electric charge to build up in photoelectric elements (CMOS or CCD) inside the camera. Lots of light makes lots of charge, less light makes less charge. In other words, an image that the camera sees is translated into brightness values - black, grey and white to you and me.
To turn this back into a colour image you need to take more than one photo, and place a filter over the top of the camera so that only light at certain wavelengths is seen.
If you do this for red, green and blue light then you get three different black and white images like this:
red green blue
If you combine these together using a program like Photoshop or GIMP you get a a false colour composite. You can then tweak this to make it look how you want it.
Does it look like you'd really see it? I guess it depends on the person, but it's close enough for most of us.
* Note that I'm only guessing that the above Phoenix images were taken using red, green and blue filters - I have no information about them - but they seem to be pretty close.