This image contains six smaller pictures of portrait orientation. They show the twin towers from their top to where the buildings surrounding them obscure them. The tower on the right has already been hit and is billowing smoke from the upper floors. Behind the towers is a clear cloudless light blue sky.
Frame 1: The tower on the right is billowing thick grey smoke from the top. Most of the smoke seems to be coming from the far side, although a quarter of the way from the top smoke can be seen coming out of the building from the side closest to the camera.
Smoke is being blown swiftly away to the left of the picture. The top of the left hand tower is covered by this smoke.
At the left, half way up the visible height of the tower is a small speck of a plane. This is flying towards the camera and banking towards the left hand tower as though turning at moderate pace.
Frame 2: The plane has disappeared. An orange cloud about twice the width of the tower now obscures the left hand tower at the height the plane was in the previous frame.
The cloud is roughly shaped like a squashed oval. It contains many colours. Yellow is predominate. There are red tinges in places, and grey smoke around the center of it.
At the bottom of this cloud debris is falling. It looks like masonary or perhaps a falling paper confetti.
Frame 3: The left cloud has now increased in size. It is now shaped somewhat like a cauliflower head or a stylised love heart. The two bulbs on the left and right are bright orange, boiling and swirling. Thick black smoke covers the bottom third.
The debris has increased in volume and now looks like a rushing waterfall springing from the base of the explosion. It is grey in colour, the same as the exterior of the towers.
Frame 4: The entire top of the tower from the height where the plane was first seen to the top is invisible behind the cloud. The top half of the left tower is now obscured in a massive ball of flame and smoke.
Not much fire can be seen in this shot. Perhaps through readjustment of the camera what little fire that peeks through the cloud is red.
The thick black smoke has expanded outwards more and now fills the frame to the left hand side. It also extends out to the right where it appears to touch the other tower. The clouds of smoke join each other in one mass cloud, and the wind is blowing them to the left.
Debris is still showering down from the point of impact. A little fire peeks out here.
Frame 5: No fire is visible. One large cloud of grey, dusty, black smoke covers most of the upper picture. The smoke from the left hand tour mixes with the smoke from the right hand tower into one gigantic cloud.
It may be possible to imagine the cloud of smoke as a grey fish shaped like an oval reaching down from the top left corner and taking a bite out of the right hand tower two thirds of the way down.
Debris is still falling, although discrete chunks are no longer visible. It looks more like dust.
Frame 6: The cloud is now huge. It has moved up into the air until less than the top eight of the building is covered. This may remind you of the mushroom cloud
that an atomic explosion creates. There is a large mushroom, and the stalk is the left hand tower. From the mushroom top dust, now coloured white, is falling.
This seems to have temporarily cleared smoke away from the right hand tower whose left hand side, closest to the cloud, can now be seen.
The cloud is forming a shadow on itself.
Source: Reuters, Yahoo
This series of photographs shows hijacked United Airlines Flight 175 as it approaches (upper L) and impacts the World Trade Center's south tower (L), bursting into flames and raining a hail of debris on lower Manhattan September 11, 2001. A gaping hole in the north tower (R) can be seen following a similar attack earlier in the day. Three hijacked planes crashed into major U.S. landmarks September 11, destroying both of New York's mighty twin towers and plunging the Pentagon in Washington into flames, in an unprecedented assault on key symbols of U.S. military and financial power. REUTERS/Sean Adair