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Mars Orbiter Photographs another Mars Orbiter
rde writes "We're all familiar with blurry photographs of UFOs, but NASA have gone one better; the Mars Global Surveyor has photographed fellow satellite Mars Odyssey as it whizzed past. This is the first instance of one extraterrestrial satellite photographing another."
Can someone explain to me why the Odyssey appears twice in the image? I can't for the life of me figure it out, and the explanation they posted really isn't helping.
How am I supposed to fit a pithy, relevant quote into 120 characters?
My understanding of optics isn't too good. Isn't this the kind of thing where you trade amazing resolution for something else? Does this camera require massive amounts of light? Would it work when photographing something not directly reflecing the light of the sun, such as on the night side of Mars?
Don't save Windows XP! http://www.petitiononline.com/jjw1xp/petition.html
They're one happy family, going on trips to exotic places and taking pictures of each other!
I guess that would a be near miss... no, a near hit... wait a minute... it's a near miss...
"The two views of Mars Odyssey in this image were acquired a little under 7.5 seconds apart as Odyssey receded from a close flyby of Mars Global Surveyor. The geometry of the flyby (see Figure 1) and the camera's way of acquiring an image line-by-line resulted in the two views of Odyssey in the same frame. The first view (right) was taken when Odyssey was about 90 kilometers (56 miles) from Global Surveyor and moving more rapidly than Global Surveyor was rotating, as seen from Global Surveyor. A few seconds later, Odyssey was farther away -- about 135 kilometers (84 miles) -- and appeared to be moving more slowly. In this second view of Odyssey (left), the Mars Orbiter Camera's field-of-view overtook Odyssey.
I think I can see the Virgin Mary in that blury photo. The scientologists are right, it really is true that we came from another planet!
This is infact tougher than it seems. Both satellites are on a polar orbit and at different speeds. And the camera on the MGS rotates as it takes pictures over this. Pretty awesome for the sheer mathematical probabilites involved
For sheer probabilites, imagine the Voyager out there in the beyond. It would be nothing short of a miracle to be spotted by a satellite from another planet.
Unless of course it bumps into the dear old gluttonous friend of ours from Trall!!
...when NASA employees with a warped sense of humour get their hands on a copy of Photoshop
"Who says nothing is impossible? Some people do it every day!" - Alfred E. Neuman
It's amazing what they've been able to get MOC to do...I can't wait to see what HiRiSe can accomplish! I'll be working with Mars Odyssey imagery in grad school next year and this image will make a fine addition to my cubicle.
a Beowulf cluster of extraterrestrial satellites?
If you do the math its because for certain values of the exact geometry there are multiple solutions in the range [0,pi] for t in the equation k.t+phi = tan(v.t) (where k is the rotational rate of the camera, v is the velocity of the flyby probe, phi is the angle of the camera to the probe at time t=0).
Obviously there are other solutions as the camera rotates round again, and I've assumed the camera is static and the probe is in a constant speed linear path.
The above maths is pretty simple, every graduate should be capable of computing it. Its hardly rocket science. Oh hang on, maybe it is!
It is a simple question of dispersion in the atmosphere. Take telescopes for instance ...Ground-based telescopes can seldom provide resolution better than 1.0 arc-seconds while the Hubble's resolution is about 10 times better, or 0.1 arc-seconds. Not just because its a good camera but because it is up where it doesnt have to deal with the atmosphere.
And the cameras on the MGS do not rely on a good lens as much as they do rely on the electronics. It uses a linear array CCD which will scan the night sky one line at a time (much like a CRT actually). And it is not limited to the visible region of the spectrum. UV and near infrared have way too much information to give than just an optical picture.
Most the pics released finally are almost always digitally enhanced and represented in the visible region of the spectrum. The kids these days will not be fired up about astronomy if all they see is an output of wavelets in an array.
The people working on the left were working in kilometers, the right side people were working in miles. Because its a fixed apeture lens they had to wait until in came into the hyperfocal legnth to take the snap. PS Don't take this seriously, conform to the norm.
It aught to be like passing one of those old handheld scanners back and forth over the same image. You'd get two mirror reflected images.
I smell a hoax! :) (Puts on tinfoil hat)
What is the shortest sig that cannot be expressed in fewer than 20 words?
I hope someone collects and preserves the Mars data for future Martian colonial history. The Martians are here and they are us.
If you RTFA, you will see it mentioned that this picture and one other picture taken by the Mars Global Surveyor were the first, not that this particular photo was the first. The European Space Agency's Mars Express was the first extraterrestrial satellite imaged in this method. The Mars Express was imaged April 20, 2005, and it seems Mars Odyssey was imaged this month (can't see a date, I've looked several places).
My other sig is just as lame
It is getting crowdy up there!
And I believe the handheld scanner would not create a mirror image either since it'd sense it's going 'backwards' and arrange the scanlines accordingly. I am slightly ashamed to admit I never tried that while I had one though so it's possible no one ever implemented that 'feature'.
Money for nothing, pix for free
OK, a purist may say that the moon lander does not qualify as a satellite, but I beg to differ here.
Look carefully, it's not the Mars Odyssey at all!
What it really it is a Martian TV satellite that proves that advanced life on Mars exists!! They are advanced enough to have designed and launched their own satellites, to pick up our TV shows.
NASA must have accidentally leaked the pictures on the Internet and are clamoring to get a good explanation out... Mars Odyssey my ass!!!
... on booze! NASA just wants to take credit for the double depiction of those spacevehicles while in fact, it's just my morning wodka that makes me see double.
Now. Where are those pink elephants and Dumbo?
This is the first instance of one extraterrestrial satellite photographing another
Aren't all satellites extraterrestrial? Do we have any *intra*terrestrial or *inter*terrestrial satellites? I guess, if they crash to earth, but then, after that, I guess they're not Satellites any more.
Solomon
"Twice half-assed makes an ass whole." --Solomon K. Chang
It should be a mirror image, providing the aspect of the object hasn't changed between the two passes across the image.
Think of the picture a graph, the vertical axis being in space and the the horizontal being in time. The camera is spinning, so the bit of space it's looking at is moving, but the thing it's photograping is moving too. As the diagram on the NASA site explains, the object first overtakes the spinning camera, then as it moves further away and it's apparent speed slows, the camera overtakes it again.
Imagine you're on the motorway, looking out of the the side window as a truck overtakes you. First thing you see is the front, then the back of it as it goes past. It slows down and you pass it - first thing you see is the back, then the finally the front. This is why you'd expect the two images to be mirrored wrt each other.
But, if the object is rotating as well (and in fact at closest approach you'd be seeing it from the side while the further away it goes the more you'd be seeing it from behind so in the frame of reference of the camera it is rotating even if it's not rotating wrt to the ground below it) then the aspect could change and cancel out the expected mirroring.
The fact that the apparent length of the boom on the side relative to the height of the craft changes between the pictures suggests that the the craft probably has rotated, but it would have to have done so by enough that the boom appears to be on the _other_ side of the craft to account for the image. Tin hat brigade, over to you...
It starts with taking pictures...
Nice, but damn blurry.
What modern Obelix would say today? Of course, "Those crazy Americans!".
if a porno star photographs another porno star?
Ah, I see what you're saying. But it can't be so, because that would cause both images to be total blurs. Each image of the Odyssey must be within a single scanline of the camera. Actually, come to think of it, the camera probably takes an instant shot of a vertical strip, waits until the craft has rotated and then takes another strip. It doesn't scan like a scanner at all, it just wouldn't work, methinks.
Money for nothing, pix for free
Sattellite Tag! You're it!
Why not fork?
Camwhoring has reached outer space.
Yeah, kind of - each scan line is taken almost instantaneously (like a camera's shutter), then after a short delay the next line is taken. What you see in the next line is a question of how much the point the camera is pointing at has moved, and of any changes in what the camera is looking at. If it's flying over a piece of ground that's not moving then the result is a straighforward picture of that piece of ground (the displacement in time is irrelevant because the object hasn't changed during the period the picture was being captured) If it was pointing directly at the same point (or I should say line) on the ground while a (pretty big) mars rover drove past, each line would capture a different part of the rover and you'd end up with a perfectly decent picture of the rover (assuming it was moving with constant speed it wouldn't be distorted either) There's nothing to prevent either of these pictures being perfectly focussed and not at all blurred. Taking a picture of this fly-by is more complex because both the object and the camera are moving (admittedly this depends on your frame of reference, but let's keep this as simple as possible!). This is what leads to there being two images (mirror image as the object overtakes the camera, then normal image as the camera overtakes the object) in the frame, but the principle is the same - there's no reason to expect the picture to be blurred.
Or can someone explain, why there are no stars in the background?
Later that day, Mars Odyssey filed a restraining order against Mars Global Surveyor with claims of stalking.
One line blog. I hear that they're called Twitters now.
Is it really that spectacular, som e white dots on a black background?
.NL, you're just mad because nothing Euro pulled this trick off first? Give these guys some credit for thinking up some interesting new tests with the hardware they've already got flying around out there.
You'd see it better if you took your head out of your ass.
It's meaningful because it's a dramatic demonstration of precision control in the imaging systems, and an impressive show that what we know about the orbital mechanics involved is spot on.
I guess that funding for them flows though the press
If it wasn't picked up in places like this, and by the press, then the only way that the tangible progress and twists and turns of these projects would be seen outside of a very small group of people would be for them to advertise that, at some expense. And then you'd complain that they spent money on that.
Does nasa need so much funding...
Yes, and then some. Personally, I think this is a great exercise, and it passes the Geek Interest test really well. Is there any chance that, being from
Don't disappoint your bird dog. Go to the range.
http://saturn.jpl.nasa.gov/news/press-release-deta ils.cfm?newsID=522
So I don't think that's exactly the first instance.
Well, I guess you could quibble.
-- ac at work (quibble, what a great word)
You raise a very important question: who was the first one to fart in space?
Surely I'm not the only one who looked at that image and saw birds of prey.
Andypoo.
~ 135 km range: *-x
~ 90 km range: o--X
:-D
Its on the Wing, there is something out there on the wing!
This is all on a sound stage in Nevada, a really poorly lit sound stage with a .3MP camera phone. You can see Lee Harvey Oswald just off to the right in the shadows.
Money for nothing, pix for free
Amazing...we send probes all the way to Mars to they can photograph...each other.
Kinda like when Americans visit other countries...all they want to do is talk to other/i> Americans.
____
~ |rip/\/\aster /\/\onkey
The lunar command module and landers photographed and filmed each other on all six successful Apollo missions to the moon. Also, Apollo 8 (which didn't land), filmed a rendezous with a lander as it took place around the moon.
The article uses the wording, not "extraterrestrial", but "while orbitting another planet..."
The article is correct, article poster is wrong.
Pavlov wouldn't be so famous if he'd used a can opener instead of a bell.
From the description, one of the images should be the mirror image of the other - one is from a forward scan, and one is from a backwards scan. Someone pointed this out to me.
I suspect that they used some sort of filter on their raw data, to correct for distortions, and also to correct for the inversion effect.
That's a couple of the vipers launched from Battlestar Galactica. They think they've finally found Earth, and are quite confused as to why they've renamed it Barsoom. The damn cleric in the Tombs of Kobol was a bit drunk when he made the map to Earth.
I mean, we really are in stone age. That could be anything. That could be a blob, it could be a light bulb exploding in a dark room. I need concrete evidence that that was what NASA claims it was.
e vastator2.jpg
If I saw something like this
http://wso.williams.edu/~rfoxwell/starwars/pics/D
there would be no doubts in my mind.
But NASA? Pffffft.
Cassini did this just last year... I can't believe NASA forgot already ;)
In general I'm with you on that reponse. The parent was just being cynical. I'd go as far as the head up the *ss.
But the whole "is it NASA or the Europeans?" jealously thing seems completely one-sided to me. The parochial defensiveness is all coming from the US side of that fence. Where are all the Europeans gloating when something from NASA cracks up? I've never seen anything close to what happened with the Beagle. Speaking as a US citizen, let's let that one drop. We just look like jerks when we bring it up, over and over, as if it wasn't a funhouse mirror of ourselves we were shadowboxing.
"Fundamentalism" isn't about divine morality. It's about human authority.
Does this remind anyone of this bit from the Simspsons?
Syntax error: loose != lose, affect != effect, then!=than
Does anyone else think the "satellite" in that image looks like a Viper from Battlestar Galactica?
Mars Odyssey
Viper
Good to know Mars is protected from the Cylons!
"I'm not, like, that smart. I, like, forget stuff all the time." -- Paris Hilton
Shortly after the pictures were taken, both spacecraft fired their orbital thrusters, making it the first time that two spacecraft had changed their orbit around the same planet while in view of eachother. After that, both spacecraft stopped firing their thrusters, the first time manuvers had ended for two spacecraft in view of eachother in orbit around another planet. When asked for comment, a NASA spokesperson said "There is hardly a dry pair of pants left in the mission control center."
Why didn't they take photos of it before they launched it? It would have been a lot cheaper.
I believe that one of the Apollo Command Modules was photographed by the Lunar Lander while orbiting the Moon. Or vice versa. As they were in orbit around the Moon, and not Terra, I think that should count as the first time.
--- Generation X: The first generation to have SIG lines inferior to their parents... ---
Oh no! Mars Odyssey blinked!
Well, back it up and take another picture. Make sure the "red eye" setting is on too.
Say, "Fuzzy Pickle", Mars Odyssey.
Show me on the doll where his noodly appendage touched you.
Google Map shows a snapshoot of... swamp gas? Weather balloon? UFO?
to have taken it on the ground! what they send em to mars for?
Brain(s): 0.0% user, 1.3% system, 0.1% nice, 98.6% idle
Wouldn't it just be simpler to take a pictures of the Odyssey spacecraft on Earth before the launch? It seems kinda wasteful to wait and do it 90 million miles away...
What, me worry?
Oh really, you must be a master debater?
Well, for what I've read, this was not the first close encounter by these two crafts. It was the first time this was captured on the camera. I'm not completely sure if they did this shot on purpose or not (the blackness suggests they did). But there is little or no scientific value in it.
Results from that marsis radar would be interesting, and be real science. A blurry picture with 64pixels representing another spacecraft is not.
None whatsoever. But likewise, is there any chance that, with you being from
This space is intentionally staring blankly at you
Getting crowded out there!
Tsunami -- You can't bring a good wave down!
Even out there, there is no privacy.
"Crackpot Photographs Truman Again."
You can't handle the truth.
It's meaningful because it's a dramatic demonstration of precision control in the imaging systems, and an impressive show that what we know about the orbital mechanics involved is spot on.
Yet, when these tourists took a picture of our beloved and divine top dog geek (sometimes blasphemously called "Face on Mars" in other backward developing planets in this Solar system) it was a cat litter picture, presented upside down.
What gall! (quoted and translated from "Mars Sol Mirror")
Im sure that this will popup on coasttocoastam and be laid out as a government conspiracy ... with ties to the CIA,NSA, Platon , Aristoteles and so on.
OK, now. Step back and look at the tone of your first comment. It's snide, and it's condescending. I'm not uncomfortable seeing that you're from overseas, and connecting that with the prevailing tone on such things. I found the original post interesting, as did obviously a lot of other people. Suggesting that it's just another US space agency money-grubbing ploy does have a certain slant to it, wouldn't you say? Given the overwhelmingly anti-US posture of most European comments here on slashdot, I suppose I was just anticipating the expected thread that would, as usually, really be more about ragging on the US and its various agencies (like NASA) than about the actual technical issues or cool geekiness at hand. And of course, referring to some interesting image-grabs, like the ones being discussed, as "every fart" that the program produces... that little bit of backhanded dismissiveness does say something about your opinion of the program, of NASA, and of course, about those of us funding it. If I made an incorrect association between that deliberate tone on your part, and the fact that you go out of your way, in your posts, to identify yourself as being from the Netherlands, well, then that was my mistake. I still like aged Gouda, though. Not so much tulips.
Don't disappoint your bird dog. Go to the range.
http://maps.google.com/maps?q=airport&ll=33.647046 ,-84.411231&sll=33.748889,-84.388056&spn=0.006341, 0.007864&sspn=1.154297,1.855359&t=k&hl=en
Find the MD-80 taking off (runway 8R). Keep scrolling right, and you'll see the same airplane every 3/4 mile or so.
That's a space station..
All the worlds indeed a
No, this is the first reported instance. Reported in public, on Earth, at least.
--
make install -not war
http://www.msss.com/mars_images/moc/2005/01/24/ind ex.html
Here's a cool picture of the Opportunity rover as imaged from orbit.
Like many geeks, I love this space exploration stuff!
Read Heinlein's 1953 Revolt in 2100, now more than ever.
No, not pictures of another spacecraft, but the Viking lander team testing the (scanning) camera system had it take a group shot of the team out in the desert. As the camera scanned past individual team members, they'd run around and join the group from the other end. Several people show up in that picture two and three times.
-- Alastair
As for your prejudice against europeans or me: I don't care, please try to stay on topic.
Apology accepted. Please remember that most people over here do not make cheese or grow tulips, just like you are probaly not herding your cattle from horseback while shooting indians...
This space is intentionally staring blankly at you
Does this mean that this is an I.F.O.?
Three Texas surgeons were playing golf together and bragging about surgeries they had performed.
One of them said, "Hellyeah, I'm the best surgeon in Texas. A concert pianist lost 7 fingers in an accident, I reattached them, and 8 months later
he performed a private concert for the Queen of England."
One of the others said. "Y'all, that's nothing. A young man lost both arms and legs in an accident, I reattached them, and 2 years later he won a
gold medal in field events in the Olympics."
The third surgeon said, "You old boys are amateurs. Several years ago a cowboy who was high on cocaine and alcohol rode a horse head-on into a
train traveling 80 miles an hour. All I had left to work with was the horse's ass and a cowboy hat. Now he's President of the United States!"
Give a man a fish and you have fed him for today. Teach a man to fish, and he'll say "WHERE'S MY FISH, YOU IDIOT?"
Apology accepted. Please remember that most people over here do not make cheese or grow tulips, just like you are probaly not herding your cattle from horseback while shooting indians...
Well, I would be herding my cattle, but the Indians took them all when I ran out of ammo. I've switched over to German hunting dogs now, though they make terrible dairy products (the dogs, not the Germans).
Actually, I'll bet that many people in Europe would be surprised just how many gun-owning, horse-riding country-folk there still are in the US, very few of which are idiots, Indian-killers, or otherwise the stereotypes one might expect. On the other hand, one of my favorite artists (Rein Poortvliet) is Dutch, and liked to own the same kind of hunting dogs that I do. I also spent years working for a Dutch family here in the US (they were Venemans), and he loved to make fun of my Scando-heritage, with is about three quarters. The Rasmusens (on one side of the family) he assured me were really mostly good for loading ships, and the Kuykendaals (on the other side) were, as he put it, translating, "the people from Chicken Valley." He loved Gouda too, though, and reminded me that it's not pronounced "gew-da". On the other hand, he was not a very good businessman sometimes, and his company got gobbled up by a much larger one. Given his personal clunkiness as a business manager, I feel that dealing with him for years as an IT person earned me the right to poke fun at at least some people from his home town, while perhaps not the entire country. And, while you can jab at me for mentioning tulips, I think you can credit me with the restraint I used in not mentioning windmills or wooden shoes. That's just how sensitive I am.
Don't disappoint your bird dog. Go to the range.
Seriously, what is it with Slashdot and this common grammatical error? It seems as if the majority of people on this site use the wrong form of verbs when referring to a company or organization.
My take on it is that they're trying to sound proper, but they aren't really that familiar with the proper rules of grammar.
When referring to the company or organization as an entity, it is a singular noun. Rarely will it be a plural noun. I see this incorrect usage in nearly every thread. Simply looking at the company's webpage and seeing how they refer to themself would give you a pretty good idea of the proper usage.
In NASA's case:
http://www.nasa.gov/about/highlights/index.html
NASA is, NASA has, etc. Singular.
How many rovers are there on Mars? and already there's traffic.
More details are available for Malin Space Science Systems. Additional photos, diagrams, and the like. Including an image of the Mars Express orbiter.
"There's only two things I hate in this world. People who are intolerant of other people's cultures, and the Dutch." - Nigel Powers
Cool cool cool.
I count 5 copies of the plane.
-
- - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
Thanks for the info.
Wow look at the Vipers in that picture. Looks like Adama has almost found earth, eh?
Did Oddyssey take a picture too? =)
at 90km the picture looks like crap. like any other ufo picture we know. and secondly in a few miles diffrence, the light shadown should be diffrent. both look identincal aside for the fack that is smaller. another hoax from nasa to give us somethign to talk about?
Lizard "Never let them set limits on your mind!"