Bad Astronomy

Revealing the Universe: the Hubble Extreme Deep Field

Astronomers using the Hubble Space Telescope have created the deepest multi-color* image of the Universe ever taken: the Hubble Extreme Deep Field, a mind-blowing glimpse into the vast stretches of our cosmos.

Check. This. Out.

Yegads. [Click to cosmosenate, or grab the bigger 2400 x 2100 pixel version.]

This image is the combined total of over 2000 separate images, and the total exposure is a whopping two million seconds, or 23 days! It’s based on the original Hubble Ultra Deep Field, with new observations added in since the originals were done. It shows over 5500 galaxies - nearly everything you see in the picture is a galaxy, an island universe of billions of stars. Only a handful of individual stars in the foreground of our own galaxy can be seen.

Here’s some detail from the image:

The variety of galaxies is amazing. Some look like relatively normal spirals and ellipticals, but you can see some that are clearly distorted due to interactions - collisions on a galactic scale! - and others that look like galaxy fragments. These may very well be baby galaxies caught in the act of forming, growing. The most distant objects here are over 13 billion light years away, and we see them when they were only 500 million years old.

In case your head is not asplodey from all this, I’ll note that the faintest objects in this picture are at 31st magnitude: the faintest star you can see with your naked eye is ten billion times brighter.

So, yeah.

I’ll note that the purpose of this and the other deep field images is to look as far away and as far back in time as we can to see what the Universe was like when it was young. The wealth of data and scientific knowledge here cannot be overstated.

But I suspect, in the long run, the importance of this and the other pictures will be their impact on the public consciousness. We humans, our planet, our Sun, our galaxy, are so small as to be impossible to describe on this sort of scale, and that’s a good perspective to have.

But never forget: we figured this out. Our curiosity led us to build bigger and better telescopes, to design computers and mathematics to analyze the images from those devices, and to better understand the Universe we live in.

And it all started with simply looking up. Always look up, every chance you get. There’s a whole Universe out there waiting to be explored.

The folks at Hubble will be holding a public interactive discussion of the HXDF image on Google+ at 13:00 Eastern (US) time on September 27th, where you can ask astronomers questions. Tune in and learn more!

Image credit: NASA, ESA, G. Illingworth, D. Magee, and P. Oesch (University of California, Santa Cruz), R. Bouwens (Leiden University), and the HUDF09 Team

* In 1998 a single-color image was taken with the STIS camera on Hubble, and reached similar depth. It would take some serious analysis to know which image sees fainter objects!

Related Posts:

- Astronomers have found when and how the cosmic fog was lifted (a brief history of the young Universe)
- Another record breaker: ultra-deep image reveals ultra-distant galaxy
- Record-breaking galaxy found at the edge of the Universe
- Hubble digs deep to see baby galaxies