Sunday, April 5, 2015

Infoporn: The Best Images of the Deep Universe (So Far)

Infoporn: The Best Images of the Deep Universe (So Far):

The European Southern Observatory released an incredible set of images today that give the best-ever view of the deep universe. It’s a stunning new peek at one region of space—the Hubble Deep Field South (HDF-S)—that reveals many previously invisible galaxies, along with new information about how they move and how far away they are.

The new discovery is all thanks to the recently-installed MUSE instrument on the ESO’s Very Large Telescope, based on the very high mountain of Cerro Paranal in the very dry Atacama Desert of northern Chile. (High altitude and dry air make for much better astronomical observations.) Until now, astronomers observing the deep universe—including NASA researchers using the Hubble Space Telescope—had to use separate instruments over the course of days to take images of the sky and measure the physical properties of the stuff in it. MUSE (for Multi Unit Spectroscopic Explorer) is the first instrument capable of doing both.

MUSE is two things: a camera that images celestial light-emitting objects, and a spectrograph that measures the wavelength of that light. Using the instrument, astronomers at ESO don’t just receive an image full of pixels. They also receive information about the intensity of the pixel’s component colors—information that lets them learn about a galaxy’s distance from Earth, its elemental composition, and even its rotation. And thanks to adaptive optics that improve resolution, MUSE can see not just bright nearby galaxies, but very faint ones as well.

The spectrograph in the MUSE instrument creates thousands of individual images of the sky, sorted by wavelength from violet to red. Many galaxies emit only a specific wavelength, flickering into view when the spectrograph isolates that color.  European Southern Observatory

“It was like fishing in deep water, and each new catch generated a lot of excitement and discussion of the species we were finding,” said MUSE principal investigator Roland Bacon in a press release. “The greatest excitement came when we found very distant galaxies that were not even visible in the deepest Hubble image.”

In the latest data, ESO astronomers used MUSE to measure distances for 189 galaxies, including some that are more than 12.8 billion light-years away. MUSE also found more than twenty very faint objects that Hubble had never been able to see before.

Now that MUSE has shown its stuff, Bacon and his colleagues expect to follow up on this data with observations of the Hubble Ultra Deep Field and other ill-known spaces of the universe. ESO has already used the instrument to track the collision of spiral galaxy ESO 137-001 as it crashes spectacularly into the Norma Cluster. Hopefully the images from those observations turn out just as stellar.