October 10, 2012
Astronomers Use Near Infrared Technology To Study Numerous Galaxies Simultaneously
April Flowers for redOrbit.com - Your Universe Online
Some 24 robotic arms attached to a new high tech instrument have been transported from Edinburgh, Scotland to a Chilean mountaintop in the hope that some of the key questions surrounding the beginnings of the Universe will be answered in greater detail than ever before.
The KMOS will now be fitted to one of the four telescopes that makes up the Very Large Telescope (VLT) at Paranal, Chile to provide astronomers with a far quicker solution to uncovering details about galaxies and their properties.
KMOS is unique in its ability to image numerous galaxies simultaneously, either in clusters or in isolation. In both cases, KMOS is still able to see the individual properties of each single galaxy. Previously, it has taken years to identify individual galaxies, while KMOS will be able to capture the same amount of detail in just two months.
The 24 cryogenic arms with gold-plated mirrors on their tips can be moved individually into place to pinpoint the light coming from distant galaxies with extreme accuracy.
“KMOS represents a pivotal step in our quest to scrutinise the distant Universe. The ability to observe in the near-infrared 24 galaxies simultaneously is an enormous leap forward compared to any other current instrument. KMOS will allow a much faster survey speed “¦ most of the observations done by similar near-infrared spectrographs over the last 10 years could be done in just two months with KMOS," explained Dr. Michele Ciracuolo, lead instrument scientist for KMOS at UK ATC.
Astronomers will be able to make a detailed study of the mass assembly and star formation in distant, high red-shift galaxies with this new capability. This will address fundamental questions about when these galaxies first formed and how they have evolved over time. The ability to observe multiple galaxies at once will enable scientists to build up large statistical samples of galaxies at different epochs. These samples are needed to help unveil the physical mechanisms that shape the formation and evolution of the galaxies.
KMOS uses integral field spectroscopy and obtains spectra over a two-dimensional area to create detailed pictures that covers entire galaxies. Each segment of a galaxy is analyzed simultaneously and given physical and chemical properties, allowing both the galaxy as a whole as well as each individual part to be measured, and creating a comprehensive picture.
“For each of the galaxies, KMOS will give an incredible amount of information. It´s not just a picture of a galaxy, but 3D spectroscopy providing the spatially resolved physics and the chemistry and the dynamics. This is crucial to understand how galaxies assemble their mass and shape their structure as a function of cosmic time, up to the formation of the very first galaxies, more than 13 billion years ago,” said Michele Cirasuolo.
One major challenge for KMOS is that it has been designed to work in cryogenic conditions below minus two hundred degrees Celsius. These conditions are necessary to observe distant galaxies at near-infrared wavelengths. Unless cooled, the thermal emission from the instrument will overwhelm the faint signal from the astronomical sources.
"It´s excellent to see the UK playing a leading role in the development of such a sophisticated piece of technology and overcoming some very complex engineering challenges on the way. This instrument will now take its place on a world leading telescope to help improve our knowledge and understanding of the universe around us," said David Willets, Minister for Universities and Science.