Resolving the Nearest Gravitational Lens

The object 2237 + 0305 is a 15.7-magnitude spiral galaxy, located 400 million light years away in Pegasus, which was discovered in 1984 and spectroscopically determined to have its light contaminated by emissions from a quasar 80 times farther away from the earth. High resolution images have been obtained which exhibit multiple quasar images with matching spectra, implying that 2237 + 0305 is a gravitational lens. A comparison of four 100-sec exposures in blue light with two in the IR has distinguished between the lensed images and the lensing galaxy's core. Since the center of the galaxy does not lie on a line joining the two images of the quasar, the galaxy must have a more complex mass distribution than that anticipated for the spherical bulge of the galaxy.