US astronomers have detected large amounts of neutral hydrogen and a lack of elements heavier than helium in a quasar thought to by in an exceptionally young part of the universe.
The quasar in question (ULAS J1120+0641) was discovered in 2011 and has a redshift (z) of 7. A star's redshift is a measure of how far its electromagnetic emissions are shifted towards the red end of the spectrum and is caused by the quasar moving away from the point of observation, in this case Earth, as the universe expands. With z = 7, the light coming from the quasar represents a time when the universe was just 772 million years old (about 5.6% of its current estimated age).
The infrared spectral analysis performed by Robert Simcoe’s group at the Massachusetts Institute of Technology, Cambridge, used measurements from the Magellan Baade telescopes in Chile. The analysis shows that the hydrogen around the quasar had not been ionised by starlight, nor was it enriched in the heavier element products of fusion in the later lifetimes of stars.
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