Six years of collecting data and images and another three years of calibrating the images has resulted in Canada-France-Hawaii Telescope’s final Legacy Survey.
“This is a very clear map of a specific area of the sky,” CFT’s Jean-Charles Cuillandre said, adding the survey provides a census of sorts for that area. “It’s a starting point for study.”
The survey is a tool for other astronomers, he said.
Telescope officials announced the project’s completion Friday. Officials called the survey a “unique and powerful multicolor collection of data,” that “probes an extremely large volume of the universe, gathering tens of millions of galaxies, some as far as 9 billion light-years away, and provides a treasure trove for many years of astronomical research.”
Astronomers from CFT on Mauna Kea began making the observations used in the survey in 2003, and continued through 2009. They then calibrated the data, obtained in five color bands covering the optical domain from blue to red, including nearultraviolet and nearinfrared, officials said in the announcement. The data show about 38 million objects, many distant galaxies in various stages of evolution. The survey is comprised of about 15,000 images, each about 1 gigabyte of data.
“Without the (legacy survey), we would never be where we are,”said Raymond Carlberg, a professor and researcher at the University of Toronto, in a written statement about the survey’s completion. “Tackling the core scientific challenges led the various teams to investigate new methods in astronomical data processing and calibration: this will remain another important legacy that future surveys will most certainly rely on.”
The prime goal of the survey was to learn more about dark matter, which astronomers said dominates the universe, but cannot be seen or identified. Their objective was to precisely measure several hundred supernovae, “which are excellent standard candles for measuring galaxy distances,” CFH officials said. The force of dark force energy expands as it spreads, they added.
