U-M is the only U.S. university that has signed the agreement to participate in the project led by the European Southern Observatory
The European Southern Observatory, or ESO, has signed an agreement with a large international consortium that includes the University of Michigan for the design and construction of the Multi-Object Spectrograph, or MOSAIC.
The instrument will be part of the 39-meter Extremely Large Telescope, or ELT, which will be the world's largest optical telescope when completed in about four years. With the ability to measure light from more than 200 sources simultaneously, MOSAIC will be used to trace the growth of galaxies and the distribution of matter from the Big Bang to the present day.
"This instrument and this telescope will be, in almost all cases, better than the JWST in terms of its power to see the distant past and in terms of its fineness of detail," said Christopher Miller, U-M professor of astronomy.
More than 30 institutions from 13 countries are collaborating on MOSAIC (a full list is available on the ESO website). U-M is the only U.S. university that has signed this agreement to participate in the MOSAIC instrument.
Miller is also part of the MOSAIC board and several more U-M faculty are involved in the early stages of planning. That includes Sally Oey, Oleg Gnedin and Sean Johnson, who leads a scientific subgroup for MOSAIC, among others.
"The idea was that Michigan would get involved early enough so that our faculty, our staff, our postdocs and our students would have an opportunity to be involved in building the plan to do the science," Miller said.
Unlike the JWST, known for taking breathtaking images of the cosmos from its space-based vantage point, the ELT will operate on Earth. ESO's ELT is currently under construction in Chile's Atacama Desert, a unique place on Earth to observe the skies.
When it sees first technical light later this decade, the ELT is poised to revolutionize what we know about our universe. U-M is supporting the construction of the telescope's MOSAIC instrument, a powerful spectrograph that will split light into its component wavelengths. This enables astronomers to determine important properties of astronomical objects, such as their chemical composition or temperature.
"MOSAIC represents a final, and critical piece, of U-M's investment in the ESO 39-meter ELT instrumentation program," said Michael Meyer, professor and chair of the U-M Department of Astronomy. "It combines the light-gathering power of the ELT with the advantages of a multi-object spectrograph to undertake surveys that cannot be done with any other capability."
MOSAIC will conduct the first exhaustive inventory of matter in the early universe, lifting the veil on how matter is distributed within and between galaxies and greatly advancing our understanding of how present-day galaxies formed and evolved. It will also be able to take a close look at the gas surrounding galaxies and identify the chemical elements within it.
The instrument will use the widest possible field of view provided by the ELT, operating in both visible and near-infrared light, and will be able to analyse the light for more than 200 objects simultaneously.
"That's what gets me excited. The term that we use for it is multiplexing," Miller said. "We're used to getting information on astronomical objects one at a time, but now we're getting to 10 times that, even 100 times that. And out of that comes the new discoveries and new science."
