Leigh Fletcher
@leighfletcher.bsky.social
Planetary scientist, Dad-in-training, space enthusiast, Professor based at the University of Leicester
https://linktr.ee/leigh.fletcher
https://orcid.org/0000-0001-5834-9588
https://linktr.ee/leigh.fletcher
https://orcid.org/0000-0001-5834-9588
Pinned
Leigh Fletcher
@leighfletcher.bsky.social
· Nov 16
#Uranus reaches 2024 opposition tomorrow. For more than 30 years, #Hubble has watched the shifting Uranian seasons, from southern summer solstice (seen by Voyager 2 in 1986), through equinox in 2007, and (hopefully) on to northern summer solstice in 2030. #planetaryscience 📸 NASA/ESA/STScI/Fletcher
Looking to start a PhD in Physics & Astronomy in 2026? The team @physicsuol.bsky.social have announced their STFC-funded projects on offer next year, spanning astrophysics, planetary science, and space instrumentation. Deadline: Jan 18th, contact us to learn more!
le.ac.uk/study/resear...
le.ac.uk/study/resear...
November 7, 2025 at 1:32 PM
Looking to start a PhD in Physics & Astronomy in 2026? The team @physicsuol.bsky.social have announced their STFC-funded projects on offer next year, spanning astrophysics, planetary science, and space instrumentation. Deadline: Jan 18th, contact us to learn more!
le.ac.uk/study/resear...
le.ac.uk/study/resear...
Reposted by Leigh Fletcher
In 2023, #NASAWebb observed a spectacular light show on Jupiter, the largest planet in our solar system. The planet’s auroras are hundreds of times brighter and more energetic than Earth’s. Credit: NASA, ESA, CSA, J. Nichols (University of Leicester), M. Zamani (ESA/Webb). 🔭 🧪
November 4, 2025 at 3:23 PM
In 2023, #NASAWebb observed a spectacular light show on Jupiter, the largest planet in our solar system. The planet’s auroras are hundreds of times brighter and more energetic than Earth’s. Credit: NASA, ESA, CSA, J. Nichols (University of Leicester), M. Zamani (ESA/Webb). 🔭 🧪
End of an amazing week @stsci.edu, enormous thanks to @chrisinbaltimore.bsky.social & the ESA team for making me feel so welcome, and to all the researchers from STScI, Johns Hopkins, and APL that came to chat. I'm going home brimming with ideas, and in awe of the work everyone's doing with #JWST.
October 31, 2025 at 7:39 PM
End of an amazing week @stsci.edu, enormous thanks to @chrisinbaltimore.bsky.social & the ESA team for making me feel so welcome, and to all the researchers from STScI, Johns Hopkins, and APL that came to chat. I'm going home brimming with ideas, and in awe of the work everyone's doing with #JWST.
Fourth day of meetings and talks here in Baltimore, and I'd like to say a massive thank-you to those who decided that I was only allowed to meet people called Sarah on Thursday afternoon. Some top-quality trolling there, almost spat out my coffee. #SarahThursday
October 30, 2025 at 1:30 PM
Fourth day of meetings and talks here in Baltimore, and I'd like to say a massive thank-you to those who decided that I was only allowed to meet people called Sarah on Thursday afternoon. Some top-quality trolling there, almost spat out my coffee. #SarahThursday
Thanks to the team at Johns Hopkins Applied Physics Laboratory for hosting me today: home of Dragonfly quadcopter to Titan (model below), Parker Solar Probe, New Horizons to Pluto, DART asteroid impactor, and more. Talked HabWorlds, JWST, heliophysics and exoplanets, all in one exhausting day.
October 28, 2025 at 11:18 PM
Thanks to the team at Johns Hopkins Applied Physics Laboratory for hosting me today: home of Dragonfly quadcopter to Titan (model below), Parker Solar Probe, New Horizons to Pluto, DART asteroid impactor, and more. Talked HabWorlds, JWST, heliophysics and exoplanets, all in one exhausting day.
Over in the *alternate timeline*, I'm at Goddard Spaceflight Centre today chatting to colleagues about JWST and future missions to explore the furthest reaches of our Solar System. But unfortunately we appear to be stuck in *this timeline,* with my NASA colleagues furloughed due to the shutdown.
October 27, 2025 at 12:34 PM
Over in the *alternate timeline*, I'm at Goddard Spaceflight Centre today chatting to colleagues about JWST and future missions to explore the furthest reaches of our Solar System. But unfortunately we appear to be stuck in *this timeline,* with my NASA colleagues furloughed due to the shutdown.
I'm in Baltimore this week, meeting colleagues at Space Telescope and staying near Johns Hopkins' Homewood campus: a beautiful, peaceful campus in the autumn sun, all red brick and marble styled after the Homewood house (1800s, now a museum).
October 26, 2025 at 1:36 PM
I'm in Baltimore this week, meeting colleagues at Space Telescope and staying near Johns Hopkins' Homewood campus: a beautiful, peaceful campus in the autumn sun, all red brick and marble styled after the Homewood house (1800s, now a museum).
Reposted by Leigh Fletcher
ESA’s Jupiter Icy Moons Explorer (Juice) spacecraft is ready to aim its instruments at interstellar comet 3I/ATLAS! 🪐☄️
Here’s what’s happening and why it’s such a rare opportunity 🧵
Here’s what’s happening and why it’s such a rare opportunity 🧵
October 24, 2025 at 2:22 PM
ESA’s Jupiter Icy Moons Explorer (Juice) spacecraft is ready to aim its instruments at interstellar comet 3I/ATLAS! 🪐☄️
Here’s what’s happening and why it’s such a rare opportunity 🧵
Here’s what’s happening and why it’s such a rare opportunity 🧵
Reposted by Leigh Fletcher
Maybe “it’s easier to make an ocean world than we thought.”
Research by Caleb Strom @uofnorthdakota.bsky.social, comments by Richard Cartwright and Chloe Beddingfield @jhuapl.bsky.social. Story by @astrokimcartier.bsky.social. eos.org/articles/tin...
Research by Caleb Strom @uofnorthdakota.bsky.social, comments by Richard Cartwright and Chloe Beddingfield @jhuapl.bsky.social. Story by @astrokimcartier.bsky.social. eos.org/articles/tin...
Tiny Uranian Moon Likely Had a Massive Subsurface Ocean - Eos
Ariel’s tempestuous subsurface ocean may have once composed more than half its total volume.
eos.org
October 24, 2025 at 3:24 PM
Maybe “it’s easier to make an ocean world than we thought.”
Research by Caleb Strom @uofnorthdakota.bsky.social, comments by Richard Cartwright and Chloe Beddingfield @jhuapl.bsky.social. Story by @astrokimcartier.bsky.social. eos.org/articles/tin...
Research by Caleb Strom @uofnorthdakota.bsky.social, comments by Richard Cartwright and Chloe Beddingfield @jhuapl.bsky.social. Story by @astrokimcartier.bsky.social. eos.org/articles/tin...
Reposted by Leigh Fletcher
Before #NASAWebb, it had been 30+ years since astronomers looked closely at Neptune. With Webb, scientists imaged the planet’s auroras and studied its atmosphere, including unexpectedly finding a significant drop in temperature—all at a distance.
Credit: NASA, ESA, CSA, STScI. 🔭 🧪
Credit: NASA, ESA, CSA, STScI. 🔭 🧪
October 23, 2025 at 2:33 PM
Before #NASAWebb, it had been 30+ years since astronomers looked closely at Neptune. With Webb, scientists imaged the planet’s auroras and studied its atmosphere, including unexpectedly finding a significant drop in temperature—all at a distance.
Credit: NASA, ESA, CSA, STScI. 🔭 🧪
Credit: NASA, ESA, CSA, STScI. 🔭 🧪
A day off to decompress, despite the stormy skies. #Leicester's Bradgate Park is fabulous in the autumn colours, fallow deer everywhere. This 850-acre park, a rocky moorland covered in bracken and woodland with the River Lin running through it, is just north of the city and spectacular year round.
October 23, 2025 at 3:57 PM
A day off to decompress, despite the stormy skies. #Leicester's Bradgate Park is fabulous in the autumn colours, fallow deer everywhere. This 850-acre park, a rocky moorland covered in bracken and woodland with the River Lin running through it, is just north of the city and spectacular year round.
Reposted by Leigh Fletcher
wanna feel old?
the date Marty traveled to in the future was ten years ago today
the date Marty traveled to in the future was ten years ago today
October 21, 2025 at 2:06 PM
wanna feel old?
the date Marty traveled to in the future was ten years ago today
the date Marty traveled to in the future was ten years ago today
Reposted by Leigh Fletcher
🔊Announcing a new Physics/Astro PhD scholarship scheme in Edinburgh, for students from a Black heritage, inc mixed Black background. Please help me spread the word. The scholarship covers all tuition fees, living costs & research travel. #blackinSTEM 🔭👩🔬⚛️
ℹ️: www.ph.ed.ac.uk/studying/pos...
ℹ️: www.ph.ed.ac.uk/studying/pos...
October 20, 2025 at 3:52 PM
🔊Announcing a new Physics/Astro PhD scholarship scheme in Edinburgh, for students from a Black heritage, inc mixed Black background. Please help me spread the word. The scholarship covers all tuition fees, living costs & research travel. #blackinSTEM 🔭👩🔬⚛️
ℹ️: www.ph.ed.ac.uk/studying/pos...
ℹ️: www.ph.ed.ac.uk/studying/pos...
Friday night after a long week. Time for a laugh with @mattgreencomedy.com at @theytheatre.bsky.social in #Leicester
October 17, 2025 at 6:56 PM
Friday night after a long week. Time for a laugh with @mattgreencomedy.com at @theytheatre.bsky.social in #Leicester
Folks were tracking #JWST proposals to see if Cycle 5 would break records (again). With success rates<10%, that means ~2500 of these amazing ideas will not get time, so will be coming right back at Cycle 6. So.... why not extend Cycle 5 and offer twice as many hours to halve the stress...?
October 16, 2025 at 12:47 PM
Folks were tracking #JWST proposals to see if Cycle 5 would break records (again). With success rates<10%, that means ~2500 of these amazing ideas will not get time, so will be coming right back at Cycle 6. So.... why not extend Cycle 5 and offer twice as many hours to halve the stress...?
Reposted by Leigh Fletcher
Excellent piece from the Planetary Society highlighting some of the human stories of NASA's workforce losses: www.planetary.org/articles/400...
4,000 gone: Inside NASA’s brain drain
In exclusive interviews, ex-NASA scientists speak out on the impact of the agency's mass departures.
www.planetary.org
October 15, 2025 at 4:42 PM
Excellent piece from the Planetary Society highlighting some of the human stories of NASA's workforce losses: www.planetary.org/articles/400...
Between the lowest and highest proposal numbers I've seen, there are already 1600 new #JWSTCycle5 proposals, ~14hrs before the deadline (8:00 pm US Eastern Daylight Time)...
The JWST Cycle 5 "Procrastination Monitor", i.e. Molly's proposal counter submission form, is up an running. Please fill it out if you have data to add to it. And do share! #JWSTCycle5
docs.google.com/forms/d/e/1F...
docs.google.com/forms/d/e/1F...
JWST Cycle 5 Proposal Procrastination Monitor
An anonymous way to monitor JWST proposal submission times
In the email from proposal-submission@stsci, the subject line will be like, "JWST Phase I Proposal 3434 submission 4 received". Here, 3434 =...
docs.google.com
October 15, 2025 at 9:58 AM
Between the lowest and highest proposal numbers I've seen, there are already 1600 new #JWSTCycle5 proposals, ~14hrs before the deadline (8:00 pm US Eastern Daylight Time)...
Reposted by Leigh Fletcher
Just a normal dy in the solar system. Jupiter on october 13th observed from Paris.
October 14, 2025 at 7:21 AM
Just a normal dy in the solar system. Jupiter on october 13th observed from Paris.
Reposted by Leigh Fletcher
Are you looking for our Public Lecture Series? The 2024 and 2025 lectures are now available on this YouTube channel playlist. 🔭 🧪
STScI Public Lecture Series - YouTube
The STScI Public Lectures Series held monthly presentations on all aspects of astronomy and space telescopes for several decades. Due to changes in funding, ...
youtube.com
October 13, 2025 at 7:17 PM
Are you looking for our Public Lecture Series? The 2024 and 2025 lectures are now available on this YouTube channel playlist. 🔭 🧪
Animation of #Uranus from JWST NIRCam, taken on October 6th as part of a calibration programme, but showing lots of little discrete clouds around the north polar cap. See Melina's thread for full details:
I also made an animation of the rotation of the planet. This also uses the F162M filter.
October 9, 2025 at 6:48 PM
Animation of #Uranus from JWST NIRCam, taken on October 6th as part of a calibration programme, but showing lots of little discrete clouds around the north polar cap. See Melina's thread for full details:
Reposted by Leigh Fletcher
One NASA science mission saved from Trump’s cuts, but others still in limbo arstechnica.com/space/2025/1...
One NASA science mission saved from Trump’s cuts, but others still in limbo
“Damage is being done already. Even if funding is reinstated, we have already lost people.”…
arstechnica.com
October 9, 2025 at 11:19 AM
One NASA science mission saved from Trump’s cuts, but others still in limbo arstechnica.com/space/2025/1...
Reposted by Leigh Fletcher
First images of comet #3I/ATLAS from Europe's Mars orbiters 😍
Observing the comet from 30 million km away, #ExoMars reveals the halo of gas and dust surrounding the comet's nucleus.
Read more 👉 www.esa.int/Science_Expl...
🔭🧪
Observing the comet from 30 million km away, #ExoMars reveals the halo of gas and dust surrounding the comet's nucleus.
Read more 👉 www.esa.int/Science_Expl...
🔭🧪
October 7, 2025 at 2:51 PM
First images of comet #3I/ATLAS from Europe's Mars orbiters 😍
Observing the comet from 30 million km away, #ExoMars reveals the halo of gas and dust surrounding the comet's nucleus.
Read more 👉 www.esa.int/Science_Expl...
🔭🧪
Observing the comet from 30 million km away, #ExoMars reveals the halo of gas and dust surrounding the comet's nucleus.
Read more 👉 www.esa.int/Science_Expl...
🔭🧪
Sundays are for bringing 35-year-old Sierra Cosworths back to life on the Scalextric. Tiny parts tested my eyesight, fingers raw from rubbing down tarnished tracks, but it's aliiiiive, and the boy is off his playstation for a few hours....
October 5, 2025 at 4:34 PM
Sundays are for bringing 35-year-old Sierra Cosworths back to life on the Scalextric. Tiny parts tested my eyesight, fingers raw from rubbing down tarnished tracks, but it's aliiiiive, and the boy is off his playstation for a few hours....
Reposted by Leigh Fletcher
SIX postdoc jobs (!) going at the new Leverhulme Centre for Space and Humanity at the University of Leicester, directed by @andrewfutter.bsky.social If you're in the social sciences/humanities and working on outer space, have a look!
Research Associate in Humanity and Space in Leicester | University of Leicester Recruitment Team
View details and apply for this Research Associate in Humanity and Space vacancy in Leicester.
The Leverhulme Centre for Humanity and Space (LCHS), based at Space Park Leicester, is seeking up to...
jobs.le.ac.uk
October 3, 2025 at 1:22 PM
SIX postdoc jobs (!) going at the new Leverhulme Centre for Space and Humanity at the University of Leicester, directed by @andrewfutter.bsky.social If you're in the social sciences/humanities and working on outer space, have a look!