Einstein Cross

QSO 2237+0305
Observation data (Epoch J2000)
Constellation Pegasus
Right ascension 22h 40m 31s
Declination +3° 21′ 30.3″
Redshift 1.695
Distance 8,000,000,000 ly (2,500,000,000 pc)
Type LeQ
Apparent dimensions (V) less than 2"
Apparent magnitude (V) 16.78
Other designations
LEDA 69457, Z 378-15
See also: Quasar, List of quasars

The Einstein Cross or Q2237+030 or QSO 2237+0305 is a gravitationally lensed quasar that sits directly behind ZW 2237+030, Huchra's Lens. Four images of the same distant quasar appear around a foreground galaxy due to strong gravitational lensing.

The quasar is located about 8 billion light years from Earth, while the lensing galaxy is located at a distance of 400 million light years.[1] The apparent dimension of this galaxy is 0,87x0,34 arcminutes, while the apparent dimension of the cross in its center accounts for only 1,6x1,6 arcseconds.

The Einstein Cross can be found in Pegasus at 22h40m30.3s +3d21m31s.

The individual images are labelled A through D (i.e. QSO 2237+0305 A), the lensing galaxy is sometimes referred to as QSO 2237+0305 G.

See also

References

  1. ^ NASA and ESA (September 13, 1990). "The Gravitational Lens G2237 + 0305". HubbleSite. http://hubblesite.org/newscenter/newsdesk/archive/releases/1990/20/image/a. Retrieved July 25, 2006. 

External links

Coordinates: 22h 40m 31.0s, +03° 21′ 30.3″