The formation of strange flying-saucer-shaped moons embedded in Saturn's rings have baffled scientists. New findings suggest they're born largely from clumps of icy particles in the rings themselves, an insight that could shed light on how Earth and other planets coalesced from the disk of matter that once surrounded our newborn sun.
The moon Atlas can be seen in this image orbiting between Saturn's A and F rings. The view looks toward the unilluminated side of the rings from about 13 degrees above the ringplane.
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The image was taken in visible light with the Cassini spacecraft narrow-angle camera on April 29, 2007 at a distance of approximately 1.8 million kilometres from Atlas. Image scale is 11 kilometres per pixel.
This image shows Atlas, seen exterior to the bright outer edge of the A ring, and Daphnis below Atlas in this view, orbiting within the narrow Keeler Gap. The presence of Daphnis is revealed by the waves it raises in the ring material surrounding it on the edges of the gap. This view looks toward the unilluminated side of the rings from about 18 degrees above the ringplane. Bright clumps are visible in the narrow F ring.
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Images taken using red, green and blue spectral filters were combined to create this natural colour view. The images were acquired with the Cassini spacecraft narrow-angle camera on April 13, 2007 at a distance of approximately 1.8 million kilometres from Atlas. Image scale is 11 kilometres per pixel.
The Cassini spacecraft imaged the F ring, and the moon Atlas at its station just beyond the A ring edge. Atlas, which appears left of centre, is 32 kilometres across.
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This view looks toward the unlit side of the rings from about 58 degrees above the ringplane. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Feb. 10, 2007 at a distance of approximately 1.7 million kilometres from Atlas and at a Sun-Atlas-spacecraft, or phase, angle of 128 degrees. Image scale is 10 kilometres per pixel.
This image of oddly-shaped Atlas beside the edge of the A ring, was taken by the Cassini spaceprobe in visible light with the narrow-angle camera on June 30, 2006, at a distance of approximately 283,000 kilometres. The image scale is 2 kilometres per pixel.
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This view looks upward, toward the lit side of Saturn's rings. The moon has a prominent equatorial bulge, which is accentuated here by the grazing viewing angle of Cassini, making Atlas appear pointy. Cassini images revealed in 2004 that a faint ring of material coincides with the orbit of Atlas (32 kilometres across).
This image was taken on June 08, 2005 and received on Earth June 09, 2005, by the Cassini spacecraft. The camera was pointing toward the moon Atlas that was approximately 138,275 kilometres away.
The image was taken using the RED and CL2 filters. A new found ring of material, S/2004 1 R, co-orbital with Atlas has been seen between the edge of Saturn's A ring and the F ring.
From a viewing angle slightly above the ringplane Saturn's moon Atlas orbits between the broad A ring and the thin F ring. The background of Saturn's atmosphere (a uniform grey in this image) lies approximately 76,000 kilometres beyond the little moon. Atlas is 32 kilometres across.
This image was taken in visible light with the Cassini spacecraft narrow-angle camera on Feb. 18, 2005, at a distance of approximately 914,000 kilometres from Atlas. Resolution in the original image was 5 kilometres per pixel. The image has been contrast-enhanced and magnified by a factor of two to aid visibility. When viewed from the dark (unlit) side, the rings are essentially an inverse of their familiar appearance.
This image just barely resolves the disk of Atlas, and also shows some of the knotted structure for which the F ring is known.
Atlas is 32 kilometres across.
The bright outer edge of the A ring is overexposed in the picture, but farther down the image several bright ring features can be seen. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on April 25, 2005, at a distance of approximately 2.4 million kilometres from Atlas and at a Sun-Atlas-spacecraft, or phase, angle of 60 degrees. Resolution in the original image was 14 kilometres per pixel.
Atlas was discovered by R. Terrile in 1980 from photographs taken by Voyager during its encounter with Saturn. Orbital period (days) 0.6019 Mean orbital velocity (km/sec) 16.63 Orbital eccentricity 0.000 Orbital inclination (degrees) 0.0 Visual geometric albedo 0.9 Magnitude (Vo) 18.0 Mean distance from Saturn (km) 137,640