New radio astronomy survey peers through cosmic dust to investigate the Milky Way
The first results from a mammoth astronomy project aimed at mapping out the origins of our 13.8 billion year old universe have been announced today.
An international team of astronomers from around the globe taking part in the project named, COMAP (CO Mapping Array Project) will offer us a new glimpse into this epoch of galaxy assembly, helping to answer questions about what really caused the universe’s rapid increase in the production of stars.
Led by CalTech and involving researchers from The University of Manchester, the first science results from the project have just been published in seven papers in The Astrophysical Journal. Based on observations taken one year into a planned five-year survey, COMAP set upper limits on how much cold gas must be present in galaxies at the epoch studied, including the ones that are normally too faint and dusty to see.
While the project has not yet made a direct detection of the carbon monoxide signal, these early results demonstrate that it is on-track to do so by the end of the initial five-year survey and to ultimately paint the most comprehensive picture yet of the universe’s history of star formation.
Alongside the main cosmology goals of the telescope, scientists in Manchester have been focused on using the telescope to make new maps of the Milky Way. Improving on work by the WMAP and Planck space telescopes, the COMAP Galactic Plane Survey maps the Galaxy at a resolution of 4.5 arcminutes, around seven times finer than Planck.
The University of Manchester COMAP team is based in the Jodrell Bank Centre for Astrophysics and is led by Professor Clive Dickinson. Jodrell Bank is a world leader in radio astronomy-related research and technology development.
We are really proud to present a first look at the COMAP Galactic Plane Survey - a survey which hopefully will continue to serve the scientific community for years to come. Mapping the Galaxy at 30GHz, at a resolution never seen before, offers us insights into the births and deaths of stars in addition to letting us probe emission from spinning dust grains across the Galactic Plane in a way we have never been able to do before.
Thomas Rennie, PhD student at The University of Manchester said: “We are really proud to present a first look at the COMAP Galactic Plane Survey - a survey which hopefully will continue to serve the scientific community for years to come. Mapping the Galaxy at 30GHz, at a resolution never seen before, offers us insights into the births and deaths of stars in addition to letting us probe emission from spinning dust grains across the Galactic Plane in a way we have never been able to do before.
"Making these observations come with challenges, mainly as the atmosphere is not clear at 30 GHz like it is by eye. At these frequencies, the atmosphere will absorb radiation from space, and turbulence high in the atmosphere make all our observations noisier. It’s like trying to look outside through a cold window. All the condensation makes everything look clouded and confused, and it’s up to us to work out a way of making the window look clear again.”
The COMAP Galactic Plane Survey, estimated for completion in 2023/2024 will be the first large-scale dedicated radio continuum and Radio Recombination Line survey at 30 GHz. This means that not only are astronomers able to make maps of how the Milky Way appears, but it’s also possible to make specific maps of hydrogen running through the Galaxy.
The choice of 30GHz for the survey lends itself to a wide range of uses; from understanding the births of stars in Galactic Hii regions (which appear as bubbles of hydrogen gas) to examining the exploded remains of dead stars in supernova remnants. Finally astronomers are even able to survey the fingerprints of spinning dust emission by mapping the mysterious anomalous microwave emission - thought to come from spinning dust grains.
The project has received funding from the Keck Institute for Space Studies (for critical early technology development) and from the National Science Foundation (NSF), for building the Pathfinder and performing the survey. The project is a collaboration between Caltech, Canadian Institute for Theoretical Astrophysics, Jet Propulsion Laboratory, New York University, Princeton University, Stanford University, Université de Genève, University of Oslo, The University of Manchester, University of Maryland, and University of Miami.
Manchester COMAP team:
Prof Clive Dickinson (Manchester PI, JBCA, Department of Physics and Astronomy)
Dr Stuart Harper (PDRA, JBCA, Department of Physics and Astronomy)
Mr Thomas Rennie (PhD student, JBCA, Department of Physics and Astronomy)