Einstein's Cross

Einstein's Cross Q2237+030 or QSO 2237+0305 is an image of a quasar which is 8,000,000,000 light years (ly) or 2,500,000,000 parsecs (pc) away.

The quasar sits directly behind ZW 2237+030, Huchra's lens, the lensing galaxy. Four images of the same distant quasar appear around this foreground galaxy due to strong gravitational lensing.

According to its redshift, the quasar is about 8 billion light years from Earth, while the lensing galaxy is only 400 million light years away.

Amateur astronomers are able to see some of the cross using telescopes but it requires extremely dark skies and telescope mirrors with diameters of 18 inches or greater.The Einstein Cross can be seen in Pegasus at 22h40m30.3s +3d21m31s. 

 References 

Category:Quasars