NASA, ESA, R. Ellis (Caltech), and the HUDF 2012 Team

One of the Hubble Space Telescope's most iconic images is the Hubble Ultra Deep Field, a view of thousands of galaxies of all different shapes, sizes and colors. The Hubble team released a deeper version in 2012. So what's next? Going even deeper.

On Thursday a team of researchers from the Instituto de Astrofísica de Canarias in Spain released what they're calling "the deepest image of the universe ever taken from space." It looks very different from previous Hubble shots.

Enlarge Image A. S. Borlaff et al.

The original Ultra Deep Field image from 2004 is described as "a 'deep' core sample of the universe, cutting across billions of light-years."

Improvements in image processing technology helped the researchers create the new, more detailed look, which shows masses of gray areas that were previously dark in the 2012 Hubble release. This deeper view highlights distant regions of space that had been invisible.

The team worked from hundreds of original Hubble observations and processed the combined views "to recover a large quantity of light [emitted by stars] from the outer zones of the largest galaxies." Lead researcher Alejandro Borlaff tweeted that the team discovered thousands of millions of hidden stars.

The Instituto de Astrofísica de Canarias work is covered in a paper published in the Astronomy & Astrophysics journal. The researchers are making their results and data available to other scientists online through a website called the ABYSS HUDF WFC3/IR project.

To the casual observer, the new Ultra Deep Field looks like a jumble, but the Instituto de Astrofísica de Canarias says the recovered light has already shown that some of the galaxies in the image have diameters nearly twice as big as previously measured.

Hubble is a joint project of NASA and the European Space Agency. The telescope has encountered some technical difficulties throughout its life, but the space agencies hope it'll continue to function through 2025.

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