(This was meant to come out on Tuesday as is traditional, but some sort of vengeful internet gnome seems to have prevented it. Well, here it is.)
Here’s a new image from the Hubble Space Telescope - specifically, the Wide Field Camera 3 which was successfully installed this May. The picture’s of an area that Hubble’s photographed before, producing the famous Ultra Deep Field image containing some 10,000 distant galaxies. This new picture repeats the feat in near infrared light (for the benefit of human eyes the colours have been shifted, so the light which now appears red is really in the farther infrared, while the blue is only just outside our visible range).
New Hubble Ultra-Deep Filed in infrared. Click for credit and larger versions.
Take a moment to look into that picture. Each of those tiny blobs is a galaxy.
In fact this picture contains the furthest galaxies which have so far been observed: some 30 billion light-years away, their light has been travelling towards us for over 95% of the age of the Universe. We’re seeing those tiny red dots now as they were only a few hundred million years after the Big Bang, when the first generations of stars were forming.
This image looks pretty crowded with galaxies - how much space would it actually take up on the sky? The traditional answer is something like ‘the size of a grain of sand held at arm’s length’. But why just tell you when I can show you?
Ultra Deep Field image with the Moon for approximate scale. Credit for Moon photo: Luc Viatour
That’s the image above, approximately to scale with the full Moon. The Moon is only half a degree wide as seen from Earth, and some fifteen copies of this 10,000-galaxy image could stretch across it end-to-end.
Space, as I will never tire of pointing out, is enormous.
The optical Ultra-Deep Field image is here - see if you can spot which part of the region has been photographed above by lining up the same galaxy in both.
Many thanks to Luc Viatour for the full Moon photo - more of his work is here.
Also congratulations to my friend Stephen, a member of the team which measured the distance to those furthest galaxies, for getting quoted in the Times!
