The cluster CL1358+62 displays a prominent red arc in WFPC2 images obtained with the Hubble Space Telescope .
Keck spectra of the arc show { Ly } \alpha emission at 7204 Å , a continuum drop blueward of the line , and several absorption lines to the red .
We identify the arc as a gravitationally lensed galaxy at a redshift of z = 4.92 .
It is the highest redshift object currently known .
A gravitational lens model was used to reconstruct images of the high-redshift galaxy .
The reconstructed image is asymmetric , containing a bright knot and a patch of extended emission 0 ^ { \prime \prime } . 4 from the knot .
The effective radius of the bright knot is 0 ^ { \prime \prime } . 022 or 130 h _ { 50 } ^ { -1 } pc .
The extended patch is partially resolved into compact regions of star formation .
The reconstructed galaxy has I _ { AB } = 24 , giving a bolometric luminosity of \sim 3 \times 10 ^ { 11 } L _ { \odot } .
This can be produced by a star formation rate of 36 h _ { 50 } ^ { -2 } M _ { \odot } yr ^ { -1 } ( q _ { 0 } = 0.5 ) , or by an instantaneous star burst of 3 \times 10 ^ { 8 } M _ { \odot } .
The spectral lines show velocity variations on the order of 300 km s ^ { -1 } along the arc .
The Si II line is blue shifted with respect to the { Ly } \alpha emission , and the { Ly } \alpha emission line is asymmetric with a red tail .
These spectral features are naturally explained by an outflow model , in which the blue side of the { Ly } \alpha line has been absorbed by outflowing neutral H I .
Evidence from other sources indicates that outflows are common in starburst galaxies at high and low redshift .
We have discovered a companion galaxy with a radial velocity only 450 km s ^ { -1 } different than the arc ’ s .
The serendipitous discovery of these two galaxies suggests that systematic searches may uncover galaxies at even higher redshifts .