We present a suite of observations of the recently identified ultraluminous BAL quasar APM 08279+5255 , taken both in the infra-red with the NICMOS high resolution camera on board the Hubble Space Telescope , and at 3.5cm with the Very Large Array .
With an inferred luminosity of { \sim 5 \times 10 ^ { 15 } { L _ { \odot } } } , APM 08279+5255 is apparently the most luminous system known .
Extant ground-based images show that APM 08279+5255 is not point-like , but is instead separated into two components , indicative of gravitational lensing .
The much higher resolution images presented here also reveal two point sources , A and B , of almost equal brightness ( f _ { B } / f _ { A } = 0.782 \pm 0.010 ) , separated by 0 \mbox { \mbox { $ { } ^ { \prime \prime } $ } . } 378 \pm 0 \mbox { \mbox { $ { } ^ { \prime \prime } $ } . } 001 , as well as a third , previously unknown , fainter image , C , seen between the brighter images .
While the nature of C is not fully determined , several lines of evidence point to it being a third gravitationally lensed image of the quasar , rather than being the lensing galaxy .
Simple models which recover the relative image configuration and brightnesses are presented .
While proving to be substantially amplified , APM 08279+5255 possesses an intrinsic bolometric luminosity of \sim 10 ^ { 14 } \rightarrow 10 ^ { 15 } { L _ { \odot } } and remains amongst the most luminous objects known .