Pale Blue Dot, Voyager 1 image
This unique narrow-angle color image is of the Earth, dubbed 'Pale Blue Dot', is a part of the first ever 'portrait' of the solar system taken by Voyager 1. The spacecraft acquired a total of 60 frames for a mosaic of the solar system from a distance of more than 4 billion miles from Earth and about 32 degrees above the ecliptic. From Voyager's great distance Earth is a mere point of light, less than the size of a picture element even in the narrow-angle camera. Earth was a crescent only 0.12 pixel in size. Coincidentally, Earth lies right in the center of one of the scattered light rays resulting from taking the image so close to the sun. This blown-up image of the Earth was taken through three color filters -- violet, blue and green -- and recombined to produce the color image. The background features in the image are artifacts resulting from the magnification.
© NASA/SCIENCE PHOTO LIBRARY
Saturn silhouetted, Cassini image
Saturn silhouetted. Cassini spacecraft image of Saturn and its ring system with the Sun directly behind. The view revealed two previously unknown rings. One, associated with the orbits of the moons Janus and Epimetheus, lies in between the outer edge of the bright main rings and the thin grey/brown G Ring. The other, associated with the orbit of the moon Pallene, lies just inside the broad and diffuse outer E ring. Earth is seen as a bright dot at the ten o'clock position between the bright main rings and the G Ring. This is a composite of 165 images taken at infrared, visible light and ultraviolet wavelengths by the Cassini spacecraft on 15th September 2006, while it was around 2.2 million kilometres from Saturn.
© Nasa/Jpl/Space Science Institute/Science Photo Library
Watson and Crick with their DNA model
^BCOMMERCIAL USE REQUIRES CLEARANCE.^bThe discoverers of the structure of DNA. James Watson (b.1928) at left and Francis Crick (1916-2004), with their model of part of a DNA molecule in 1953. Crick & Watson met at the Cavendish Laboratory, Cambridge, in 1951. Their work on the structure of DNA was performed with a knowledge of Chargaff's ratios of the bases in DNA and some access to the X-ray crystallography of Maurice Wilkins and Rosalind Franklin at King's College London. Combining all of this work led to the deduction that DNA exists as a double helix. Crick, Watson and Wilkins shared the 1962 Nobel Prize for Physiology or Medicine, Franklin having died of cancer in 1958. Photographed in the Cavendish Laboratory, University of Cambridge, UK, in May 1953.
© A. BARRINGTON BROWN/SCIENCE PHOTO LIBRARY