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Phoenix Mars Lander Updates
spandex_panda writes "There are a few pictures of the Mars Lander on the ground — you can see its parachute and its heat shield a few kilometers away, too. There's a very cool looking picture of it floating down, actually captured while it's in the air with its parachute out!" We also have a YouTube video all about the robot arm that will dig down and probably find a groundhog who we all hope will see his shadow.
I didn't see any link to the NASA site with the complete set of pictures: http://www.nasa.gov/mission_pages/phoenix/images/index.html
Yes.
If there is no atmosphere/air on Mars, why in the world do we have a parachute on the lander?
Because Mars does have an atmosphere, complete with weather, sandstorms and such.
Also, "captured while its in the air" might not be an appropriate way to summarize the article as there is no air on Mars.
Mars does not have "air" (as in: 78% nitrogen, 21% oxygen, some random other stuff). Its atmosphere is mainly CO2, and is at much, much lower pressure than Earths. Still, it is definitely an atmosphere and not a near-vaccuum like you'd find on the moon.
Heck, I don't think this is a troll - it's an interesting question. So I looked, and found this:
Abandoned Spaceships on the Moon
Basically, the Lunar Reconnaissance Orbiter will get some 0.5 meter resolution pictures of the Apollo landing sites. It launches sometime after November 28th of this year (which really is 2008 - the government's telling the truth on that one). Enjoy!
The English word fart is one of the oldest words in the English vocabulary.
It's as close as you can get to reconstructing the real color from a series of monochrome images taken with different color filters.
or is it something NASA arbitrarily adds to impress viewers with notions about "the red planet"?
That Mars is pretty much reddish all over, with some white at the poles, can be easily verified from Earth with a telescope.
Part of the descent was filmed by the Mars Reconnaissance Orbiter:
http://apod.nasa.gov/apod/ap080527.html
Not quite what you want, but close.
Nerd rage is the funniest rage.
We have satellites with cameras circling mars.
http://www.nasa.gov/images/content/230838main_PSP_008579_9020_descent.jpg
The wikipedia also has a link to an image from the Mars Reconnaissance Orbiter that lcoates the Phoenix spacecraft. It is 10 pixels wide but you still recognize the solar arrays.
http://www.nasa.gov/mission_pages/phoenix/images/press/PSP_008591_2485_RGB_Lander_Inserts.html
The Wise adapts himself to the world. The Fool adapts the world to himself. Therefore, all progress depends on the Fool.
If there is no atmosphere/air on Mars,
What? Mars DOES have an atmosphere.
Seven puppies were harmed during the making of this post.
In the case of Phoenix, no - as the stuff NASA is interested in is a couple of inches down. At any rate, they use multiple small thrusters to minimize the amount of disturbance and contamination.
That advantage comes with a pair of powerful disadvantages: First, the airbag systems sharply limit the size of the probe - both in dimensions and in weight. Secondly, the airbag systems are heavy - they take up a higher percentage of the possible landed weight.
or is it something NASA arbitrarily adds to impress viewers with notions about "the red planet"
It's a fairly accurate representation of what Mars would look like to the human eye.
The thing is none of the cameras on board the rovers or Phoenix take pictures in a "conventional" manner. Instead the imaging devices have a series of filters designed to focus on a specific range of wavelengths (ultraviolet, infrared, etc.). Those black and white images you see are the results of a picture being taken through one of those filters. This is why some images of the same scene will appear darker than others.
NASA can then take these images and composite them together to give a representation of what the surface would look like to the human eye.
OK, class...
Today's lesson in Internet humor will discuss text-based simulations of real-life behavior.
Sometimes, it aids for delivery of humor to juxtapose two replies or comments together in such a way that one is hidden and the other is the official or formal one. A good example in common speech would be in Top Gun when the main character says one thing to the teacher and "coughs" a different response into his hand. The hidden, coughed, reply is shared with those nearby so they can share the deceit.
For the humor impaired, or non-human readers out there, humor is often a social construct of sharing the joke or hidden meaning. Get it?
A long time ago, before chat rooms or blogs, a common internet medium was a program called "talk". The primary difference of modes today was that each "talker" got half the screen and just typed away. You could type something and then backspace it away but the person on the other end would see the entire exchange. So they knew both the early response and the second.
"^H" is representative of Control-H which in several terminal types is basically backspace. When people now type one thing followed by a series of "^H" they are simulating this early behavior of "talk" or even earlier and more mundane habit of hiding a hidden response or comment (cough, cough).
Now, be sure to return next week (especially those semi-sentient programs out there) to tackle the more difficult topic of sarcasm.
The robotic arm is scheduled to start digging on about sol 10 or thereabouts. After that, it really depends on how hard the soil is as to how long it will take to dig. Some samples of the loose soil will be delivered to the TEGA and MECA instruments before that, I believe.
A long time ago, before chat rooms or blogs, a common internet medium was a program called "talk". The primary difference of modes today was that each "talker" got half the screen and just typed away. You could type something and then backspace it away but the person on the other end would see the entire exchange. So they knew both the early response and the second.
"^H" is representative of Control-H which in several terminal types is basically backspace. When people now type one thing followed by a series of "^H" they are simulating this early behavior of "talk" or even earlier and more mundane habit of hiding a hidden response or comment (cough, cough).
There are two more facts that will help people and machines trying to understand the funny:
1) The "talk" program would send the literal backspace key to the talk client you were communicating in order to erase the character off their screen.
2) Different terminals may be using different codes for backspace, such that it was possible that when someone tried to erase something they typed it would look to be properly deleted on their end, yet on the other end it would appear as a literal series of "^H"s, making both the original word and attempt to erase it obvious.
So an additional layer of the humor in the case of using "^H"s is that it is supposed to simulate the hidden comment, revealed unintentionally and unwittingly.
The enemies of Democracy are
There's generally two issues I've seen. The first is that they may use 2 filters instead of 3. If they use 2 filters, then they usually have to fudge the tint to match the actual color that a human would see. It also means that some color variations may not show up in the image because 2 filters is "lossy" in the color realm. Some of the first Phoenix color images were 2-filter images according to the descriptions.
The second issue is when the filters do not represent the wavelengths that the human eye sees (even if they do use 3 or more). Most missions since the Voyagers carry approximately a dozen filters that span into infrared and ultra-violate, as well as the visible spectrum we are familiar with. It is usually too expensive to send back an image of the same scene through all 12 available filters. Thus, they tend to pick a few that span a wide range or that highlight features of a particular subject[1]. In most cases, these don't match what the eye sees, even if there are filters that could if used. But often one can approximate what the eye sees if the colors of the subject are fairly well known based on previous images or earth-based observations. One can then re-process the images accordingly in the lab. This was done a lot with rover images.
The bottom line is that the color images are usually only approximations for one or both of the above reasons. Because transmitting images costs lots of money, picking filters that match the human eye accurately often conflicts with the scientific goals of the mission.[2]
I'm sure better color images will come in the coming weeks and months. They're just getting their bearings right now. But they are likely to still be only approximations.
[1] For example, it was discovered from Earth scopes that one can see the surface of Titan through its clouds on a very specific wavelength. The Voyagers didn't have such a filter, but one for that very specific wavelength was added to the Cassinni probe.
[2] Another compromise technique is to send very low-resolution images of a given scene in more filters, such as human-friendly wavelengths. These are then combined with hi-res images such that the detail (texture) is clear, but the colors may bleed a bit. This is because the texture info comes from the hi-res image but the color info from the low-res ones.
Table-ized A.I.
The photo is taken from a very oblique angle. Phoenix is actually about 20 km in front of the crater, but the viewing angle makes it look like it's inside. The crater is called "Heimdall" crater, and it's just NE of the landing site.
A thorough mapping of the moon is about to be done by the Lunar Reconnaissance Orbiter (LRO) http://lunar.gsfc.nasa.gov/ in preparation for NASA return to the moon to establish a permanent base via Constellation http://www.nasa.gov/mission_pages/constellation/multimedia/aresV_orbit.html.
I don't know if this is true with Phoenix or not, but it is true for Spirit & Opportunity and I have no reason to suspect it would be different for Phoenix.
The scientists are not really that interested in the visible light spectrum, the camera captures other wavelengths which are more telling of material composition and the like.
This is half-true. It's more accurate to say that scientists are interested in a lot more than the visible light spectrum. The MER Pancam actually mostly operates in the visible portion of the spectrum. The CCD itself is sensitive from about 400 (violet near the edge of UV) nanometers to 1100 nanometers (near IR) and the two cameras have different sets of filters (and the "left eye" camera has a filterless setting).
The Mini-TES instrument on the rovers operates mostly in the IR (167 bands!). Both VIS and IR can be used to do compositional science.
here: the thing in the air and the thing on the ground
like phosphorescent desert buttons singing one familiar song