Yesterday I posted my attempt to capture
Einstein’s Cross, a gravitationally lensed quasar that is located exactly behind a closer galaxy. That attempt, my 4th of that object, was not exactly successful.
I feel a bit better about this result for Andromeda’s Parachute. It is another quasar that is gravitationally lensed by a closer galaxy into a series of dots. The object is located in the constellation of Andromeda at a declination of +47 degrees. Its discovery was announced in the 2017 paper, “
Discovery of the first quadruple gravitationally lensed quasar candidate with Pan-STARRS” by Berghea et al.
In this example, the lensing galaxy (labelled G in the mouseover) is really not visible through the noise. The paper indicates that it is an elliptical galaxy located about 5.6 billion light years away.
The quasar (J014709+463037) is located about 11 billion light years away. It is revealed in 4 point images (labelled A to D in the mouseover). The 4 point images range from 15 to 18 magnitude.
As the light of the quasar passes by the foreground galaxy towards us, the galaxy acts like a lens to show us multiple images of the same background quasar. The lensing result is a series of dots, not a ring or arc as one might expect.
Whereas the Einstein Cross has a width of 1.6 arc-seconds, the width here of Andromeda’s Parachute is much wider at about 4 arc-seconds. That difference is enough to allow me to resolve the lensed quasar images, which I could not do for the cross.
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