SINFONI confirms distance record for galaxy
Using the SINFONI spectrograph at the ESO's Very Large Telescope (VLT), a European team of astronomers has
measured the distance to the most distant galaxy so far. With a redshift of 8.6, they are seeing it when
the Universe was only about 600 million years old. This detection was only possible by using the SINFONI
instrument, which combines the SPIFFI spectrograph built at the Max Planck Institute for Extraterrestrial
Physics with adaptive optics. The results are published in the 21. October issue of the journal Nature.
Image taken with the Hubble Space Telescope in 2009, where the galaxy was first identified (see enlarged area)
as a robust candidate distance-breaking-object.
Credit: NASA, ESA, G. Illingworth (UCO/Lick Observatory and University of California, Santa Cruz) and the HUDF09 Team.
Studying these first galaxies is extremely difficult. By the time that their initially brilliant light gets
to Earth they appear very faint and small. Furthermore, this dim light falls mostly in the infrared part of
the spectrum because its wavelength has been stretched by the expansion of the Universe - the so-called redshift.
"The power of the VLT and the sensitivity of its SINFONI spectrograph allows us to actually measure the distance
to this very faint galaxy and we find that we are seeing it when the Universe was less than 600 million years old,"
said Matt Lehnert (Observatoire de Paris) who is lead author of the paper reporting the results.
The team found that they had clearly detected the very faint glow from hydrogen at a redshift of 8.6, which
makes this galaxy the most distant object ever confirmed by spectroscopy. At this early time, less than a
billion years after the Big Bang, the Universe was not fully transparent and much of it was filled with a
hydrogen fog that absorbed the fierce ultraviolet light from young galaxies. The astronomers can now look
at one of the galaxies that cleared out this hydrogen fog. Apart from the distance record, this finding
therefore has interesting astrophysical implications.
Spectroscopic confirmation of a galaxy at redshift z=8.6
M. D. Lehnert, et al.
Nature, 21 October 2010
ESO press release
SPIFFI pages at MPE