University of Leicester’s insights from JWST to be showcased at Space Telescope Science Institute

A University of Leicester astronomer has been invited on his own ‘grand tour’, as he visits three key sites of space science excellence to present his research.

Professor Leigh Fletcher, Professor of Planetary Science at the University of Leicester, will deliver the 2025 ESA Distinguished Lecture for the European Space Agency on 30 October. Entitled ‘JWST as a New Voyager for Giant Planet Systems’, it will take place at the Space Telescope Science Institute in Baltimore – the home of the Hubble Space Telescope and JWST.  The lecture will showcase Leicester’s research using JWST to study the planets in our own solar system.

Professor Fletcher will spend a week meeting the team at STScI, where the Hubble Telescope and JWST are controlled, during which he will also travel to NASA’s Goddard Spaceflight Center and Johns Hopkins University Applied Physics Laboratory in Maryland to present to their teams. 

The first three years of JWST scientific operations have provided a treasure trove of new discoveries in our Solar System. Not since Voyager’s Grand Tour have we had a facility capable of spatially-resolved infrared spectroscopy of the four giant planet systems with shared techniques and instrumentation. In the late 1970s, the Voyager spacecraft completed flybys of Jupiter, and of Saturn and its moon Titan, while Voyager 2 sailed on to encounter Uranus and Neptune in the 1980s, as part of a ‘Grand Tour’ of the outer planets of our solar system.

While known for its stunning imagery of distant space phenomena such as the Cosmic Cliffs, JWST has also been used by the Leicester team to reveal the giant planets in our own solar system in a new light – specifically in the infrared to explore their temperatures and chemical composition. 

JWST has become an integral component of planetary science research at Leicester, from the weather and chemistry of giant planet atmospheres, to the powerful and ever-changing auroras, the icy surfaces and atmospheres of moons like Ganymede, and the incredible rings of the giant planets.  

These new discoveries provide a stepping stone to help shape the exploration from future giant planet missions, such as ESA’s JUICE mission, NASA’s Europa Clipper and Dragonfly, and future endeavours like an ambitious mission to the Uranus system.

Professor Leigh Fletcher from the University of Leicester School of Physics and Astronomy said: “JWST has opened up new windows for discovery, probing wavelengths that were simply too dark and too faint to be observed by any previous observatory.  So far we’ve used it to watch the shifting seasons of Saturn, characterise Jupiter’s northern lights and Great Red Spot, and to discover auroral emission on Uranus and Neptune for the first time.

“From those very first glimpses in 2022, when we popped the champagne corks, it’s been an incredible few years of discovery.  And with all four giant planets scheduled to be observed afresh in the next 6 months, with new wavelengths and observing strategies, this’ll be a treasure trove for many years to come.

“I’m looking forward to visiting the team at Space Telescope Science Institute, and colleagues at Goddard Spaceflight Center and the Applied Physics Laboratory, to share some of the discoveries enabled by this amazing observatory, and plan for the next generation of missions.”

The ESA Distinguished Lecture Series aims to showcase the science from ESA missions, recognize talented European astronomers, and foster collaborations in the broader international community.

Professor Leigh Fletcher specialises in the exploration of our Solar System’s giant planets via robotic spacecraft missions, ground-based astronomical facilities, and space telescopes. He is a team member for the Cassini mission to Saturn, the Juno and JUICE missions to Jupiter, and is a passionate advocate for future exploration of the distant Ice Giants. He currently leads the planetary atmospheres team at the University of Leicester.