"In this paper, we present the discovery, in the Abell 2744 cluster field, of a two-armed, grand-design spiral galaxy, with a redshift of z ∼4, when the universe was only ∼1.5 billion years old.

Redshift is also the name of the factor z indicating the relative change in wavelength due to the Doppler shift for a receding galaxy. The Doppler equation used for sound calculations cannot be ...

S. et al, 2012, MNRAS, 420, 957. "The VLT LBG Redshift Survey- II. Interactions between galaxies and the IGM at z˜ 3", Crighton, N. H. M. et al, 2011, MNRAS, 414, 28. "The VLT LBG Redshift Survey - I.