Monday, November 12, 2012

On Earth as it is in heaven

(Image and text from here)

Giant ammonite fossil on the Jurassic Coast in Dorset, England.

Ammonites are perhaps the most widely known fossil, possessing the typically ribbed spiral-form shell as pictured. These creatures lived in the seas between            240 - 65 million 
years ago, when they became extinct along with the dinosaurs. The name 'ammonite' (usually lower-case) originates from the Greek Ram-horned god called Ammon. Ammonites belong to a group of predators known as cephalopods, which includes their living relatives the octopus, squid, cuttlefish and nautilus. The largest one ever found was 9 feet across and nearly 225 million years old.

 (Image and text from here)

Discovered over 200 years ago by Charles Messier, the Whirlpool Galaxy is probably the most observed and most photographed of all distant galaxies. And no wonder! Oriented almost perfectly oblique to our perception, its two clearly defined spiral arms are so elegant that galaxies of this type came to be called “grand design” spiral galaxies.
The remarkable structure and frantic star-birthing activity in the Whirlpool Galaxy are due to two powerful gravitational forces. One is a Black Hole in the center of the galaxy, whose presence has been inferred by observation of stellar matter emitting its last dying gasp as it hurtles over the “event horizon” — the point at which the force of the Black Hole is so powerful that light waves are stretched to infinite length, creating a sort of Doppler Effect. The second is a smaller galaxy that passed right through the Whirlpool, perhaps half a billion years ago, stirring up the interstellar dust with wave after wave of gravitational shock.
The star birthing areas can be clearly seen as bright blue areas in this spectacular Hubble photo, taken in 2005.

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