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Y’know that great big GeoEye satellite photo of the Obama inauguration that everyone’s been linking to? If you go to GeoEye’s website you can download the original — a massive 8218-by-7608 JPEG that’ll squat on ten megs of your hard drive. (Granted, most of us have more storage than that dangling off our keychains nowadays.)
If you look down from the Washington Monument, you can see another satellite that was passing underneath GeoEye’s satellite as the photo was being taken.
Update: Oops, maybe not a satellite.
Ah... if you go to Google Maps, you will see the same "satellite" in the same position, only with a lot more boats tied up at it.
Sorry.
My poor old lappy nearly choked on that.
I thot it was a satellite.
I understand that the clumps of people are gathered around "Jumbotron" video displays. I'd wondered about that when I first looked at the picture yesterday.
That would have taking some astounding focal depth, to resolve another object in orbit and details on the ground at the same time.
Avram, when I saw the picture this morning I thought the same thing.
Then I found out it's really a new Coast Guard "Dragonfly" Class tidal basin attack cruiser. In summer it guards the Jefferson Memorial's shave ice concession. XD
Darth, at those distances it's probably the equivalent of having the end of a pier and the mountains on the other side of the lake both in focus. Both the satellite and the ground are probably at the equivalent of infinity for the lens.
"I understand that the clumps of people are gathered around "Jumbotron" video displays"
Either that, or they're crawling all over giant chunks of fallen ice cream.
The group on the left you can see them carrying away the pieces of a giant caterpillar who got in the way.
Shudder. I hear Mumakil have been stripped to the bone in thirty seconds when these things are on the march.
Jeff Hentosz @ 8: Then I found out it's really a new Coast Guard "Dragonfly" Class tidal basin attack cruiser.
Normally used for nabbing smugglers in Firefly-class vessels?
It's clearly a Chupacabra-class escape pod, prepositioned for Cheney's getaway.
Here's the Google Maps terrain view shot. So cute with all the little Space Paddle Shuttles at the little docking stations!
http://tinyurl.com/barra3
Clearly, the dock was designed so as to resemble a satellite from orbit, to throw off the Russians.
Has there ever been a verified case where one of the mapping satellites spotted another orbital object?
Never mind field of focus, I'm wondering what the angular diameter would be! (For that matter, just how high are those satellites? I'd guess they're relatively low.)
What, Russians can't swim?
Wow. I opened that up and thought, "wow! DC's brown and ugly in the winter." Then, I realized the brown was people.
Now that I think about it, it's an understandable mistake. But Satellite Parking is actually two miles south of the Tidal Basin.
He thought he saw a satellite
Above us, taking notes,
He looked again and saw it was
A place for pleasure boats.
"That's change we can believe! The man
Is worthy of our votes."
To Nigel at #19 - that's very sweet.
I would be amazed if two satellites ever passed close enough for that... I'd imagine they give them a bit more room for error.
My heart leaps up when I behold
A dustbin in the sky.
They have them emptied, I am told,
By dustmen who can fly.
Twinkle, twinkle, little star,
How I wonder what you are:
A satellite which spies on me,
Or just a dock for boats from sea?
Lucky that the GeoEye satellite chanced to pass almost exactly vertically over the inauguration at the right time. According to their site it visits any given location only every three days.
That isn't another satellite: That's Randy Quaid in a crop-dusting biplane coming to shoot down the GeoEye satellite.
Nigel: Very nice indeed. More Lewis Carroll!
Jim @ 25... Dusting crops where there ain't no crops?
Look!
Up in the sky!
It's a bird!
It's a plane!
It's... Suuuuperduck!
Jon @ 10 and 12... You make me giggle!
Uncle Jim @ 25... Before I knew it was an inauguration picture, I assumed it was a looping biplane. Makes it more fun to think of Quaid and what he'd be shouting.
Anyone else try to find the rows of porta-potties?
Never mind the Port-a-potties; did you find Waldo?
Wait, my eyes were closed. Can we take that picture again?
Waldo lives on "Wheelchair". That would be a different satellite.
Andrew Plotkin @ 18: You couldn't get into Satellite Parking by 11 am, so I expect the illegal overflow into the Tidal Basin was what you see in the photo.
Glenn Hauman @ 32: There's always one of you in every group, isn't there? Listen, just stand outside in the nearest field, and we'll photoshop you in later. Just don't move until we tell you it's ok.
With deep and since apoogies to Billy Bragg:
I saw two paddle boats last night
I wished on them but they weren't even satellites
Is it wrong to wish on marine hardware?
I wish, I wish, I wish you'd care
Darth @7, Tom @9,
If the satellite were using a pinhole-type camera (rather than one with a lens) to take pictures, it would be theoretically possible to capture that image with both the ground and another satellite in focus.
I'm not saying it's likely, of course.
Space is big, but there are lots of satellites, and they take lots of pictures. That part wouldn't surprise me. (One of the first times I looked through a telescope at the moon, a high-altitude jet flew directly through the field of vision, across the disk of the moon.)
What's the altitude of the GeoEye? If it's geosynchronous, and the closer satellite is in LEO, then that would be a BIG satellite.
No, geosynchronous satellies are 22,000 miles up, too far to get pictures with a resolution of 1.5 feet unless you had an amazing camera. Also the point of a geosynchronous satellite is that it stays (roughly) over one point on the earth, but spy satellites like GeoEye want to see the whole planet, which they do by going round and round in low-earth-orbit, 400-some miles up.
Yeah, elliptical polar orbits are good for spy satellites. Low over the south pole, where you don't care about stuff, and higher over the north, so you get more hang time. Also, polar orbits will eventually cover every point on Earth, if you care about that sort of thing.
Ken Brown @ 35 just cracked me up.
David @15, not a mapping satellite, but there are cases where Hubble Space Telescope images have had other satellites in them -- an example is here (scroll down to the "Power of the median" section.) Not in focus and, of course, because of the length of the exposure, a streak. That's a much easier case, though -- LEO looking up, with long exposures -- than the "short-exposure LEO looking down" that a mapping sat would require. Still, it's the only "accidental image of one satellite from another" situation I'm aware of.
And if you look at Maryland Avenue and 3rd St SW, next to the American Indian Museum, you can see the huge knot of people who were still waiting to get in at the gate to the "Silver" section.
Has anyone seen any info about what time the photo was taken? I'd be interested to know if it was actually during the ceremony, or beforehand. Just so I can properly point to which tiny dot is me. :-)
Redshift@43: I was going to post it as a puzzler to use the Washington Monument as a sundial to determine the exact time. (Which I don't know how to go about doing, but I'm sure someone here does.)
However, the picture spread on boston.com cites it as "Tuesday, Jan. 20, 2009 taken at 11:19AM EDT".
#44 Andrew: I was going to post it as a puzzler to use the Washington Monument as a sundial to determine the exact time. (Which I don't know how to go about doing, but I'm sure someone here does.)
First, determine true north, running through the Washington Monument.
Second, measure angle of shadow away from true north.
Third, determine time of meridian passage at the Washington Monument.
After that, just a little bit of calculation.
Ginger, #34, does that mean you went down?
Ginger @34: There's always one of you in every group...
By my count, there seem to be seven or eight of them in this group...
Marilee @ 46: Oh, Heck No. I did drop off my SiL and her daughter (niece-in-law?)* at New Carrollton Metro, at just before 7 am, and the parking garage was already full**. Traffic was backing up all the way onto Rt 50 West; we could see it as we came around to 495/95 north to go home. We had originally entertained thoughts of going along, back when SiL applied for 6 tickets. She got three, and very late -- like, Friday before? -- so we'd made plans to stay home and celebrate in comfort.
Jacque @ 47: Unless you count in base 7 or 8.
*They had Silver tickets, and actually did get in, although their location was on the far side of the reflecting pool, which meant they were too far away to really see the podium, and too close for the first JumboTron screen.
**This never happens on a regular workday. Also, it was not the only Metro garage that was full; all of them were filled by that time. Clearly there were a lot of people heading down to the Mall.
You are being featured on Five Star Friday!
http://www.fivestarfriday.com/2009/01/five-star-friday-edition-38.html
"schmutzie" posts for the first time.
The "five star friday" site seems kind of innocuous, but still . . .
OTOH, schmutzie's own site seems perfectly legitimate, so I may just be overly suspicious of a helpful lurker!
Ginger, #48, ah, I wondered. Sensible people stayed at home. I went to PT and played catch while standing on a small trampoline and trying not to fall down.
He's been doing Five Star Friday blogpost accolades since April.
For the record, I am a bit skeptical of the 11:19 timestamp: by then, they'd long stopped letting more people onto the Mall east of 14th Street. I also spent the better part of two hours standing in a human river at 14th and Independence, telling people to keep going past the Washington Monument, there'd be space and Jumbotrons on the other side.
I haven't seen a good picture of the Mall from the Monument back to the Lincoln Memorial yet, though; maybe they all ended up around the Reflecting Pool.
Oh, and one of the guys in my volunteer group was on Olbermann the next day talking about the NSA wiretaps. Weird day. Wonderful, but weird.
Nona -- the timestamp is plausible. I'd forgotten the exact placement of the Tidal Basin and had to go to Google; the "satellite" is a hair east of due south of the monument, so the road on the right half of the upper edge of the claim is Raoul Wallenberg Place (renamed from 15th Ave SW when the Holocaust Museum was sited just above the frame). 15th Ave runs due north/south, so the clip is rotated 90 degrees CCW from normal map display; the monument's shadow puts the time at a little after 11am local solar. (No, I don't remember where DC lies relative to the reference meridian for GMT-5, or the equation of time for 20 Jan.) 14th Ave is well out of the frame.
Mars Global Surveyor photographed Mars Odyssey, both in orbit around Mars.
http://www.nasa.gov/vision/universe/solarsystem/mgs-images.html
And Mars Reconnaissance Orbiter photographed the Phoenix lander on its way down.
http://planetary.org/blog/article/00001468/
The link in the name is a mailto, not normal for spammers; the comment is substantive and relates to a topic discussed in the thread, the links given are not to commercial sites. I'm not sure why you'd think it was spam.
Agree, #56 isn't spam; the only spammy thing about it is the single-letter name 'g'. (Note to 'g': welcome, but you could use a more meaningful moniker here.)
Satellites have seen other satellites as blurred streaks; but has one satellite ever shown up as clearly in another's photo as the 'satellite' in the GeoEye image (assuming that it's optically possible, as suggested in #9)?
I'm not sure why you'd think it was spam.
I wasn't sure- the style kind of looked spammy to me. Pushed the wrong buttons in a way. Sorry.
Also, the host from g's address looks like a perfectly reasonable personal site. Yeah, he might look like a "fly-by", but hey, that's only appropriate to the the discussion at hand! ;-)
Stick around, "g"! (But yesh, use a bigger handle.) We're really pretty mellow, it's just that we get lots of spam attempts, and we do this Neighborhood Watch thing, to help the mods clear them out.
Addressing the content, I note that even those prearranged photos are basically blurry handfuls of pixels. Of course, the Mars crafts are at the far end of a very long data-pipe!
We could introduce 'g' to 'y', who occasionally* manifests here.
*'Occasion' might be a useful addition to our Spelling Reference.
Mez writes in #62:
'Occasion' might be a useful addition to our Spelling Reference.
In eighth grade, I was the best speller in my school. I became a contestant in a city-wide spelling bee. At a certain point, I was ahead of all the best spellers from about half the schools in Miami.
"Occasion" was my downfall.
That was forty-one years ago. Last month, my sister reminded me of it. She still remembers which word I misspelled.
So allow me to second Mez's motion.
Bill Higgins # 63...
"They laughed at me at the spelling bea! Butt I'll show them!"
Does anyone else here find that the ongoing Obama-excitement reminds them of The Sultan's Elephant, in terms of public delightfulness?
http://nielsenhayden.com/makinglight/archives/007523.html
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