The galaxy in its observable timeframe was producing stars at a phenomenal rate, equivalent in mass to about 330 Suns per year.

Due to the expansion of the universe, this position is now at about 30 billion light-years (9.2 Gpc) (comoving distance) from Earth.

[7] Research published in the 24 October 2013 issue of the journal Nature by a team of astronomers from the University of Texas at Austin led by Steven Finkelstein, in collaboration with astronomers at the Texas A&M University, the National Optical Astronomy Observatory and University of California, Riverside, describes the discovery of the most distant galaxy known using deep optical and infrared images taken by the Hubble Space Telescope.

[8] To measure galaxies at such large distances with definitive evidence, astronomers use spectroscopy and the phenomenon of redshift.

The redshift observed in astronomy can be measured because the emission and absorption spectra for atoms are distinctive and well known, calibrated from spectroscopic experiments in laboratories on Earth.