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Hubble Finds Double Einstein Ring
Einstein Duble brings us news that astronomers using the Hubble Telescope have discovered an extremely rare double Einstein Ring. Occasionally, galaxies or other bright objects are located in such a way that they are behind another galaxy when viewed from Earth. When light from the further galaxy passes a sufficiently massive closer galaxy, the path of the light is bent inward from all sides, creating a "ring" effect. In this case, not one, but two galaxies are directly behind the foreground galaxy, so the gravitational lens produces two distinct rings. Quoting Presscue:
"The distribution of dark matter in the foreground galaxies that is warping space to create the gravitational lens can be precisely mapped. In addition, the geometry of the two Einstein rings allowed the team to measure the mass of the middle galaxy precisely to be a value of 1 billion solar masses. The team reports that this is the first measurement of the mass of a dwarf galaxy at cosmological distance (redshift of z=0.6)."
Proving Einstein's theory was always been about getting a little behind as it were. The solar eclipse of May 29,1919 was the first confirmation of this. And, this new discovery is much like the 191 observation only writ large, one might say glactic large.
- Minutus cantorum, minutus balorum, minutus carborata descendum pantorum.
There's a great story about the first person to accurately measure the height of Mount Everest, whose name escapes me at the moment.
His calculations came out to precisely 29,000 feet. Thinking no-one would believe such a round number, he added two feet to make 29,002 feet but was greatly annoyed by the whole thing.
Later it was more accurately measured at 29,029 feet (going from memory here) using lasers or something.