October 20, 2008

HOW THE DISTANT GALAXY WAS IMAGED: Radio waves from carbon monoxide gas in the distant galaxy
(left) were bent by the gravitational effect of another galaxy directly between the distant object and Earth (right).
The nearly-perfect alignment caused the distant object to appear as a ring when seen from Earth. This
graphic shows how the distant object would appear as one moves from Earth toward the lensing galaxy.
Some of the waves are Doppler shifted by the motions of the gas in the galaxy, and this is indicated by the colors.
Green indicates "stationary" gas; red indicates gas moving away from us, and blue indicates gas moving toward us
with respect to the rest of the galaxy.

CREDIT: Bill Saxton, NRAO/AUI/NSF

ANIMATION of above: View that an observer would see as they move from Earth to the lensing galaxy.
Once arriving at the lensing galaxy, the lensing would disappear, showing an undistorted image of the distant galaxy.
CREDIT: Dominik Riechers, Brendon Brewer

RECONSTRUCTED IMAGE of the distant galaxy, at left, and the "Einstein Ring" image seen from Earth, right.
Colors indicated Doppler-shifted radio emission from carbon monoxide (CO) gas , as explained above. 8.5 kpc equals
28 thousand light-years. The intermediate, lensing galaxy is not seen in this image, because its CO emission arrives
at Earth at radio frequencies outside the range of this observation.
CREDIT: Riechers et al., NRAO/AUI/NSF

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