October 27, 2013
Foreground clusters that will be used for gravitational lensing, taken by Hubble Space Telescope. Image credit: NASA/ESA/J. Lotz & M. Mountain,STScI
In program called The Frontier Fields, NASA will bring together their three great space telescopes in order to have the deepest look into the universe we ever had.
NASA's Hubble, Chandra and Spitzer space telescopes will have a chance to observe objects that are 100 times fainter than what they see each on their own. They will achieve this by taking advantage of a natural phenomenon called gravitational lensing. Basically, the gravitational field of a massive object that lies in the foreground is used as natural lenses, bending and focusing the light of a more distant object behind it.
In case of The Frontier Fields, six galaxy clusters will be used as lenses in course of three years in order to observe galaxies that came to be as early as a couple hundred million years after the universe was created, 13.8 billion years ago.
"The Frontier Fields program is exactly what NASA's great observatories were designed to do; working together to unravel the mysteries of the Universe" said John Grunsfeld, associate administrator for NASA's Science Mission Directorate in Washington, USA. "Each observatory collects images using different wavelengths of light with the result that we get a much deeper understanding of the underlying physics of these celestial objects."
By combining the Hubble and Spitzer space telescopes, scientist hope to measure distances and masses of galaxies more accurately than they could by using either telescope alone. Chandra is an X-ray telescope, so it will observe galaxy clusters at X-ray wavelengths and help determine their mass and measure the magnitude of their lensing power. It should also identify galaxies with massive black holes, the galaxies behind these clusters, which The Frontier Fields hopes to observe for the first time. Black holes are sources of massive X-ray radiation, so Chandra is a perfect way to identify which galaxies have them.
"We want to understand when and how the first stars and galaxies formed in the universe, and each great observatory gives us a different piece of the puzzle," said Peter Capak. He is the principal investigator for Spitzer space telescope in the Frontier Fields program. "Hubble tells you which galaxies to look at and how many stars are being born in those systems. Spitzer tells you how old the galaxy is and how many stars have formed."
Also, Hubble will be used to determine the distribution of dark matter withing the six clusters that will be used as lenses. Dark matter accounts for 26.8% of all the universes mass-energy and it is the what keeps galaxies together.
For astronomers, it is important to have a look at very distant objects because they are also a very old objects. They can be a source of valuable data answering questions about evolution of the universe.