Tuesday, 4 February 2014

CLUSTER - M13

M13 - the great globular cluster in Hercules.

Also designated NGC 6205.

Position:


RA 16h 41m 41s

DEC +36° 27' 37''

Distance: 25 000 light years. This means that the photons that crashed into my camera's sensor and made the pictures you see here left M13 during the last global glacial maximum on Earth. At that time sea levels were at their lowest, thus expanding the surface of dry land to their maximum. The inhabitants from today's Siberia were crossing the Bering land bridge and migrating South into the Americas. People were using eyed bone needles to sew garments made of animal skin and the first mining was taking place in Australia (flint).


Apparent magnitude: 5.8 (barely visible with the naked eye).

Apparent dimension: 20 arcminutes

M13 - The great globular cluster in Hercules



The negative images show two of the brightest stars around M13 - HP 81848 and HP 81673. Also visible is NGC 6207, a spiral galaxy shining at Mag 11.5 located at 46 million light years away. I'm afraid we don't know much about what happened on Earth 46 million years ago...


Negative image of globular cluster M13


M13 is some 145 light years in diameter and contains several hundred thousand stars, the brightest of which is a variable - star V11 with an apparent magnitude of 12 or so.

In 1974 the human race decided to send what is now referred to as the "Arecibo message" - it was supposed to communicate the existence of human life to hypothetical extraterrestrials. The choice of M13 was determined by the high density of stars that compose this object, the logic behind it being that chances would be higher to stumble upon a planet that may support intelligent life. This was more of a technological demonstration rather than a serious attempt to communicate - by the time our message gets there M13 will no longer be in the same place.

Regarding such attempts to broadcast our existence and location, Stephen Hawking said this: "if you're in the jungle, and have no idea what's around and how friendly or hungry other life forms may be, would you call out and show yourself?"