![Image](http://earthobservatory.nasa.gov/Newsroom/NewImages/Images/npnoctilucent_aim_2007162.jpg)
June 11, 2007 image of NLC's from the AIM satellite posted at Earth Observatory latest images.
It is impossible to take a straight down picture and have the centre blacked out.
The image wasn't taken straight down over the pole. The AIM spacecraft is in a 97.8° inclination orbit, so it never passes over the poles. Swaths of data are collected by the instruments and then mathematically projected onto a sphere centered on the pole. You can see these data bands in the image.FieryIce wrote:June 11, 2007 image of NLC's from the AIM satellite posted at Earth Observatory latest images.
It is impossible to take a straight down picture and have the centre blacked out.
Only if the camera can actually image the pole at some point in its orbit. As I noted before, the satellite is in a 97.8° inclination orbit. That means it never gets closer than about 900 km from the poles. Its camera has a 800 km field of view on the latitudinal axis. That leaves an approximately 400-500 km radius zone around the poles that cannot be imaged. You can see this zone very clearly, and the individual data stripes, in this image.FieryIce wrote:They can take a picture of a planetary pole without the blacked out area, so there is no excuse for the data block out.
Please quote who and what you are responding to. What issue exactly is being sidestepped?FieryIce wrote:You can side step the issue, go ahead but the facts remains.
Err...so are you claiming that NASA is hiding the imagery? If they had something to hide, wouldn't it be more convincing to photoshop fake data over the poles than to simply black it out. I think Chris explained the technical reason data was not taken directly over the pole pretty well. If you were to challenge that explanation or take issue with the fact that the satellite orbits at 97 degrees inclination instead of a true polar orbit I think we'd have something to discuss, but as is, I don't get what you're hinting at.FieryIce wrote:You can side step the issue, go ahead but the facts remains.
Quite impossible. Because of the curvature of the Earth, about the farthest you can see atmosphere is 700 miles. That is, at 700 miles, you are seeing the very top of the atmosphere on the horizon. You were what, something like 3000 miles south of the North Pole?zbvhs wrote:Consensus of opinion in the car was that we were seeing sunlight coming over the Pole reflected upward by the polar icecap. Could be we had one of those rare nights when skies were clear all the way north to the pole.