A Sussex University astronomer is preparing for the Christmas Day launch of the James Webb Space Telescope today.
Stephen Wilkins, head of astronomy at Sussex, leads a team of scientists who will be among the first to use the Webb Telescope to find and study the most distant objects in the universe.
The Webb Telescope is the successor to the Hubble and is due to launch at 12.20pm – or 7.20am on the eastern seaboard of America.
Dr Wilkins said: “The James Webb Space Telescope is the long-awaited successor to Hubble, which launched more than 31 years ago.
“Like Hubble, we expect Webb to transform our understanding the universe from our own backyard, the solar system, to the very first stars and galaxies to form almost 14 billion years.
“Here at the University of Sussex, we’ll use Webb to study the distant universe, including hopefully finding examples of the first stars and galaxies to form.
“I study the most distant galaxies in the universe, observed only a few hundred million years after the Big Bang.
“These galaxies are faint – partly because they’re so far away but also because they haven’t had time to form many stars yet – and their light is shifted into the infrared by the expansion of the universe.
“These galaxies are effectively ‘invisible’ to existing observatories. Webb, with its large mirror and infrared optimisation, however, should be able to see them.
“Webb is so much more powerful than its predecessors that we might find something entirely unanticipated – an ‘unknown unknown’ to quote Donald Rumsfeld.
“Astronomy is littered with examples where looking at the universe in more detail has thrown up new mysteries, eg, dark matter and dark energy.”
But what would happen if the launch failed? Dr Wilkins said: “Unfortunately there is nothing that will replace Webb’s combination of sensitivity and infrared coverage.
“However, there are a couple of other observatories coming online that will help us explore. For example, ESA’s Euclid (due to launch in 2023) and NASA’s Roman Space Telescope (late 2020s) are both wide area infrared space telescopes.
“Their wide field of view will allow us to find rare but bright galaxies present in the early universe.
“We’re also building a new generation of ground-based telescopes, including the Extremely Large Telescope (ELT). The ELT will allow us to study objects in great detail.”
What’s so special about the Webb Telescope? Dr Wilkins said: “It’s really the extremely sensitive infrared coverage and the fact Webb will obtain both imaging and spectroscopy.
“The latter is vital for probing the composition of alien atmospheres and tracking how heavy elements are built up across the history of the universe.”
