Recycled telescope to solve 'dark energy' mystery
Washington: A 45 year-old telescope is being re-purposed to create the largest 3D map of the universe and solve the mystery of dark energy, which is believed to drive the accelerating expansion of the cosmos.
Tucked inside a 14-story, 500-tonne dome atop a peak in Arizona, the telescope took in the night sky for the first time and recorded its observations in glass photographic plates.
The temporary closure sets in motion the largest overhaul in the telescope's history and sets the stage for the installation of the Dark Energy Spectroscopic Instrument (DESI), which will begin a five-year observing run next year at the US National Science Foundation's Kitt Peak National Observatory (KPNO) - part of the National Optical Astronomy Observatory (NOAO).
This day marks an enormous milestone for us, said Michael Levi DESI Director of the US Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab).
Now we remove the old equipment and start the yearlong process of putting the new stuff on, said Levi.
More than 465 researchers from about 71 institutions are participating in the DESI collaboration.
The entire top end of the telescope, its secondary mirror and a large digital camera, will be removed and replaced with DESI instruments.
A large crane will lift the telescope's top end through the observing slit in its dome.
Besides providing new insights about the universe's expansion and large-scale structure, DESI will also help set limits on theories related to gravity and the formative stages of the universe, and could even provide new mass measurements for a variety of elusive yet abundant subatomic particles called neutrinos.
One of the primary ways that we learn about the unseen universe is by its subtle effects on the clustering of galaxies, said Daniel Eisenstein of Harvard University in the US.
The new maps from DESI will provide an exquisite new level of sensitivity in our study of cosmology, said Eisenstein.
The Mayall Telescope has played an important role in many astronomical discoveries, including measurements supporting the discovery of dark energy and establishing the role of dark matter in the universe from measurements of galaxy rotation.
Its observations have also been used in determining the scale and structure of the universe. Dark matter and dark energy together are believed to make up about 95 per cent of all of the universe's mass and energy.