Scientists in the Astronomy Unit are involved in developing theory and data analysis tools for a new generation of extremely large galaxy surveys that will map out a large fraction of the observable Universe over the coming decade.
Euclid is a European Space Agency mission that will survey large numbers of galaxies in the optical and near infrared, with the aim of better understanding the nature of Dark Energy. The Euclid satellite will be capable of precisely measuring the distances to many millions of distant galaxies, and using the resulting information to measure the expansion rate of the Universe. AU members are involved in many aspects of Euclid, including the theory, forecasting, and tests of isotropy work packages.
LSST is a ground-based optical survey telescope currently under construction in Chile. It will detect hundreds of millions of galaxies by repeatedly imaging the sky for ten years, precisely measuring their shapes and colours. AU members are involved in the Theory and Joint Probes working group of the LSST Dark Energy Science Collaboration, which is tasked with combining all available information form the clustering and weak gravitational lensing of galaxies into the best possible constraints on dark energy and gravitational physics.
VISTA is the world's largest near-infrared survey telescope. Scientists at Queen Mary led its construction, with AU members Jim Emerson as Principle Investigator and Will Sutherland as Project Scientist. VISTA publicity images are available from the ESO website.
Large radio telescope arrays are now being deployed that have sufficient sensitivity to map out large and very distant regions of the Universe. AU members are involved in several cutting-edge radio experiments:
HERA is an array of 350 parabolic mesh dishes, each 14m in diameter, in a close-packaged hexagonal array, situated close to the SKA site in the Western Cape region of South Africa. It is designed to passively map the sky at low frequencies, eventually building up sufficient sensitivity to detect fluctuations in the radio emission from neutral hydrogen during Cosmic Dawn and the Epoch of Reionisation, when the first stars and galaxies lit up the universe. Queen Mary is a HERA partner organisation, with AU member Phil Bull currently working on power spectrum estimation and statistical analysis of the data.
LOFAR is a low-frequency radio array based in the Netherlands but spread across much of Western Europe. Through SEPnet, the AU has access to the LOFAR:UK facility, which is based around a LOFAR station at Chilbolton. LOFAR also targets the Epoch of Reionisation, and is an important precursor experiment for the SKA-LOW array.
SKA is a large international project to build the world's most powerful radio telescope array. SKA will eventually comprise two telescopes - a low frequency array in Western Australia designed to detect and image signatures of the first stars and galaxies, and a mid-frequency array in South Africa's Western Cape region that can detect distant galaxies, study black holes, precisely time pulsar signals, and make gigantic 3D maps of the Universe. AU members are heavily involved in the Cosmology science working group of SKA, as well as precursor experiments like MeerKAT.