In the Dark

While I was away last week there was quite a lot of press coverage (e.g. here) about the new Dark Energy Spectroscopic Instrument, which has just seen first light. I didn’t have time to mention this until now, and in any case  I have little to add to the coverage that has already appeared, but it does give me the excuse to post this nice video – which features quite a few people I actually know! – to describe  the huge galaxy survey that DESI will perform. It’s hard to believe that when I started in the field in 1985 the largest such survey, which took several years to compile, had only a few thousand galaxies in it. The DESI instrument will be able to determine spectra of more sources than that in a single pointing of the telescope that lasts about 20 minutes. Overall it should determine redshifts of over 35 million galaxies! Vorsprung durch Technik.

This entry was posted on November 4, 2019 at 2:54 pm and is filed under The Universe and Stuff with tags Cosmology, Dark Energy, Dark Energy Cosmology, Dark Energy Spectroscopic Instrument, DESI, Galaxy redshift surveys, redshift surveys. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.