ESA’s Euclid Mission, With Help from UMass, Releases First Images of the Cosmos
Earlier this month, the European Space Agency (ESA) shared the first five images from its Euclid telescope, currently located within the Sun-Earth Lagrange Point 2—1.5 million km (approximately 932,057 miles) from Earth. In preparation for this mission (and the resulting images), ESA relied on UMass researchers to study dust attenuation corrections that aided the measurements needed for the telescope to do its historic work.
ESA's Euclid mission is designed to “explore the composition and evolution of the dark universe,” examining the role that gravity plays and the nature of dark energy and dark matter. Through this telescope, ESA aims to “create a great map of the large-scale structure of the universe across space and time by observing billions of galaxies out to 10 billion light-years, across more than a third of the sky.” But as with any space-based telescope, Euclid’s success in achieving its ambitious goals relies on the effective mitigation of a key obstacle: dust.
“My involvement with the Euclid project is to provide corrections for the effects of dust in determining properties of galaxies at high redshift (large distances),” explained Daniela Calzetti, distinguished professor and head of the College of Natural Sciences’ Department of Astronomy. A redshift is an increase in the wavelength of electromagnetic radiation, such as light. “The main goal of the Euclid mission is to measure fundamental properties of the universe: dark energy and dark matter. For this, the telescope will acquire multi-color images of millions of galaxies, and from those images, one of the key properties that will be derived is their redshifts. The required accuracy of those redshifts is 3%-5%, but presence of dust can affect this determination greatly, reducing the accuracy to 10%-15%.
Along with her students, Calzetti has been working on deriving corrections for the dust attenuation in galaxies at different redshifts, enabling the project to achieve the stated accuracies and measure the geometry of the cosmos to infer the essence of the dark universe.
Beyond their benefits to astronomy in general, UMass’s contributions are furthering the university’s standing in the field, as well as the prospects of its students: “So far, this project has provided the backbone of two PhD theses: one completed in 2017 and one ongoing,” Daniela Calzetti noted. In fact, the student whose thesis concluded in 2017 was able to leverage their knowledge to obtain a postdoctoral position in Australia.
Though the Euclid mission is attempting to measure some of the most mysterious forces in our universe, these measurements will be incredibly accurate, thanks to the efforts of the UMass Department of Astronomy.