I find it hard to believe it’s been 25 years since I appeared on The Sky at Night for the first time.
A scared student in a new suit, I’d been invited by Patrick to discuss viewers’ questions, which ranged from ‘Why are there seasons?’ to ‘What, precisely, is dark energy?’.
While some of the questions are the same today, everything else is different.
in 2000. Credit: BBC
For starters, the show back then was filmed in the corner of a vast studio at BBC Television Centre in west London, with camera operators gliding around and instructions from the producers in our ears.
As the cameras got smaller, we moved to Patrick’s home, Farthings, and for many years we’ve travelled the world (well, mostly the UK).
But what has changed in astronomy in 25 years?
Professional astronomy has gone multi-messenger, with researchers regularly combining results from gravitational wave observatories and studies of particles like neutrinos with traditional techniques.
The starkest change, though, has been in what amateur astronomers can achieve from their back gardens.
What astrophotographers can now do with relatively modest equipment is simply astounding, whether looking at the deep sky or at nearby planets.
Speaking of planets, there are thousands more known than when I started on the show.
The biggest scientific advance is undoubtedly the discovery that exoplanets are common in the Galaxy.
We cover the topic regularly, sometimes focusing on the search for Earth-like worlds and sometimes emphasising the diversity of the planets that have been found.
of Pluto in 2015, with The Sky at Night team witnessing the event
Each of these systems has something to teach us about how our own Solar System has formed and evolved.
We’ve learnt, too, from our neighbouring planets. Venus, which might have phosphine-burping bacteria (the subject of a memorable programme involving a guitar, toast and a lot of excitement), but particularly Mars.
The Red Planet has been explored by the rovers Spirit and Opportunity, Curiosity and Perseverance, along with orbiters loaded with cameras and sensors, and has turned out to have a fascinating history.
Cassini explored Saturn and its moons, landing the Huygens probe on Titan and then, in 2006, discovering the fountains of Enceladus.
Juno has sent back marvellous pictures of Jupiter (guided by amateur astronomers on Earth) and, of course, we were on hand when New Horizons swept past Pluto, revealing a much more complex world of ice mountains and changing surfaces than expected.
In fact, everywhere we’ve looked in the Solar System, we’ve found new puzzles and mysteries.
Nowhere is this more true than with the Solar System’s minor bodies, from comet Churyumov–Gerasimenko explored by plucky Rosetta, to Dawn and Ceres, and more recently, small asteroids like Bennu and Ryugu.
In light of new funding challenges, we may look back on the first quarter of the 21st century as a golden age of planetary exploration.
Still, we have JWST in orbit, whose first images it was a joy to share.
We knew a large infrared telescope would be game-changing, but its discoveries – from ‘little red dots’ and mysteriously mature early galaxies to intriguing exoplanet spectra – have been magnificent.
Where we haven’t made much progress is in cosmology.
Though Planck, whose launch we travelled to see, produced the definitive map of the cosmic microwave background’s ancient light, movement on the big questions – the nature of dark matter and dark energy – has been frustratingly stalled, to the extent that the answers I gave in our recent ‘Question Time’ episode weren’t far off what I said in my first appearance.
But with a new generation of experiments coming on stream, the next 25 years could see us reporting on a new, deeper understanding of the Universe on the largest scales.
I hope so – and I hope to still be on The Sky at Night, talking about them.
This article appeared in the August 2025 issue of BBC Sky at Night Magazine
