An example of a gravitational lens effect in which four images of a background object are formed. The first such example to be detected, the quasar G2237+0305, displays four distinct images arranged symmetrically around the image of a foreground galaxy, which is acting as the lens. The lensed quasar is about 8 billion l.y. away, while the galaxy lies 500 million l.y. from us. This object is sometimes also known as the Huchra Lens after its discoverer, the American astronomer John Peter Huchra (1948–2010). Similar objects subsequently discovered are now also termed Einstein crosses.
Subjects: Astronomy and Astrophysics.