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Join the Royal Observatory Greenwich for a rare opportunity to hear astrophysicists talk about the latest research in the fields of astronomy, physics, planetary geology and space exploration.

Next lecture: Graphs that define astrophysics

8 December 2023 | 6pm-7pm

The beautiful images of the cosmos taken with telescopes have undoubtedly progressed astrophysics research over the centuries. However, it's worth celebrating the graphs that summarise our understanding of planets, stars, galaxies, cosmology and the underlying physics. In this talk, Dr. Jeff Grube discusses ten such graphs, focusing on the pioneering research behind them.

Tickets are available now.

A graph showing temperature of stars vs their luminosity. Hundreds of data points are scattered across the graph, with one data point labelled as the Sun.
The Hertzsprung-Russell diagram is one of the most important graphs in astronomy. It shows how a star's temperature is related to its brightness and can be used to trace how a star evolves throughout its life.

About the speaker

Dr Jeff Grube is a Senior Lecturer at King’s College London. He focuses on education and astrophysics. His research background is in high-energy astrophysics, previously with the VERITAS Collaboration and now with the Cherenkov Telescope Array (CTA). Jeff is fond of science museums, having previously worked as a researcher at the Adler Planetarium in Chicago for six years.

Upcoming lecture dates


  • 26 January - Dr Henrik Melin (University of Leicester)
  • 23 February - Sergi Sirera-Lahoz (University of Portsmouth)
  • 15 March - Dr Maitrayee Gupta (IRAP - Institut de Recherche en Astrophysique et Planétologie)
  • 26 April - Professor Lucie Green (Mullard Space Science Laboratory, UCL)
  • 10 May - Dr William Maslanka (King's College London)

Information about each lecture will be announced soon, so keep an eye on our website or sign up to the Think Space mailing list to keep up-to-date. You can watch recordings of some of the previous lectures below.

How do I book?

Follow the link at the top of the page to book your tickets.

Where do these lectures take place?

Until further notice, our lectures will take place online via Zoom webinars.

When do these lectures take place?

Lectures will take place on selected Friday nights during term time and will run from 6:00 - 7:00 pm. 

Keep up to date

Subscribe to the Think Space mailing list to be the first to hear about upcoming events.

Previous lectures

Check out some of our previous lectures below. Find more videos on Facebook and YouTube.

Computer simulation of galaxies forming

Solving the mysteries of the Dark Universe

20 October 2023

Fiona McAllister (Mullard Space Science Laboratory, UCL)

In the late 1990s, the Hubble telescope revealed something shocking: the Universe is expanding, and it’s getting faster. Why is it happening, and what does it tell us about the ultimate fate of the Universe? The answer is believed to lie in two mysterious entities which make up 95% of our Universe today: the expansion driving factor dubbed ‘dark energy’; and unobservable dark matter.

Cutting edge surveys, like the recently launched Euclid, will help cosmologists map the structure of the dark Universe, its cosmic history, and give us a glimpse into its future.

Speaker bio:

Fiona McAllister is a research student at UCL’s Mullard Space Science Laboratory. Their research focuses on machine learning and other statistical techniques for cosmology imaging surveys like Euclid.


How do you take an image of a supermassive black hole?

28 April 2023

Dr Ziri Younsi (Mullard Space Science Laboratory, UCL)

The gravitational field around a black hole is so strong that nothing, not even light, can escape its event horizon. Black holes have been predicted to exist for over a century, yet direct observational confirmation of their existence was long thought to be the preserve of science fiction. However, in April 2019 the Event Horizon Telescope Collaboration surprised the world with the first ever image of a supermassive black hole. In this talk Dr Ziri Younsi will explain how we can now capture images of black holes, what these images tell us about black holes and their environments, and how future experiments of this nature will advance our understanding of black holes and the origins of space, time, and the Universe itself.

Speaker bio:

Ziri Younsi is a UKRI Stephen Hawking Fellow at UCL's Mullard Space Science Laboratory. After graduating from the University of Cambridge and subsequently UCL, Ziri began working within the Event Horizon Telescope (EHT) in 2014, first as a Humboldt Fellow at the University of Frankfurt and later as a Leverhulme Trust Fellow at UCL. His research program develops and performs supercomputer calculations of black holes, underpinning the EHT's interpretation of black hole images. He is a co-recipient of the 2020 Breakthrough Prize for Fundamental Physics and the Royal Astronomical Society's 2021 Group Achievement Award. In 2022 Ziri was elected to the EHT's Science Council, and is co-lead of the EHT's Gravitational Physics working group.

Artist's impression of Juice mission going past Jupiter

What will we learn from the JUICE mission to Jupiter and its moons?

31 March 2023

Professor Geraint Jones (Mullard Space Science Laboratory, UCL)

The European Space Agency’s Jupiter Icy Moons Explorer – JUICE – is an ambitious space mission set to explore giant planet Jupiter and its large moons, and is due to launch in April 2023. Following its multi-year journey to the largest planet, it will enter orbit around it, and it will spend several years sweeping past three of the planet’s largest moons – Callisto, Europa, and Ganymede. With its suite of instruments of many different types, scientists will lern more about these fascinating worlds, as well as Jupiter itself. The final phase of the mission is particularly exciting: JUICE will orbit Ganymede – the largest moon in the solar system, larger than planet Mercury. We’ll explore what we expect to learn from this ground-breaking project.

Speaker bio:

Geraint Jones is Professor of Planetary Science at University College London’s Mullard Space Science Laboratory. After graduating at UCL, he worked at Imperial College London, NASA’s Jet Propulsion Laboratory, and the Max Planck Institute for Solar System Research, before returning to MSSL in 2007. His primary research interests are the icy moons of the outer planets, and comets. He led the recently-approved Comet Interceptor mission proposal to the European Space Agency, due for launch in 2029.

An artist's illustration of a black hole with an accretion disc and jet of gas ejecting from the black hole

How do the largest black holes form?

24 February 2023

Dr Greg Brown (Royal Observatory Greenwich)

Black holes remain some of the most popular and most intriguing objects in the Universe. The largest, known as supermassive black holes, are found at the cores of almost every large galaxy. And yet, for something so common and ubiquitous, their origins are a mystery. In this talk, Dr Greg Brown discusses how astronomers are trying to pin down the births of these behemoths and how the untimely deaths of stars in a not-so-loving embrace may just be the best way to find out.

Speaker bio:

Dr Greg Brown is an astronomer working at the Royal Observatory Greenwich. In his time in research at the University of Warwick, he studied some of the largest explosions in the Universe and the supermassive black holes hiding in distant galaxies. Combining a love of science, comedy and acting, Greg moved into science communication, where he has been eliciting anguished groans from his audiences ever since.

Artist impressions of exoplanets

Can artificial intelligence help us find alien worlds?

27 January 2023

Dr Mario Morvan (University College London)

More than 5000 planets have now been discovered in less than thirty years of search, opening wide a window on a fascinating diversity of planetary systems. And this is just the beginning, as new telescopes and missions are now designed specifically to study those brave new worlds, thus providing us with an avalanche of rich stellar and exoplanet data to analyse. Artificial intelligence is already being used today to make sense of this data automatically and help us detect and study exoplanets – planets outside of our Solar System. But could it take us to the next step and help us unravel the greatest mysteries still held by these distant worlds?

Speaker bio:

Mario is currently a research fellow at University College London (UCL). His background in physics, data science and astronomy has led him to pursue a doctorate combining these disciplines at UCL, developing deep learning algorithms to disentangle the astrophysical and instrument noise from exoplanet signals in stellar light curves. Mario also feels strongly about bridging the gap between academic research and science outreach: he has been involved in the ORBYTS education program, the ExoClock citizen science project, and has been working as an Assistant Planetarium Astronomer at the Royal Observatory Greenwich. 

Image showing mountain and rocks in foreground, with rippling emerald aurora in the sky behind the mountain, which is reflected in a pool of water

Can we predict the northern lights?

2 December 2022

Dr Michaela Mooney (University of Leicester)

The northern and southern lights, or the aurora, produce spectacular displays in the night sky. However, the energetic particles which cause these light shows pose a significant danger to technology that we rely on in our day-to-day lives, such as radio communication networks and radar systems used by planes. Since the beginning of the Space Age, scientists have been developing auroral forecast models that can predict when and where the northern lights will occur to try to minimise their impact on these essential services. In this talk we will discuss the physical processes that lead to the bright auroral displays and how current auroral forecast models work. 

Speaker bio:

Dr. Michaela Mooney is a space physics researcher at the University of Leicester. Michaela’s research focusses on the occurrence of the aurora, the link between the aurora and the dynamics of Earth’s magnetic field in the hope of limiting damage to technology and infrastructure on Earth caused by particles and radiation in near-Earth space, known as Space Weather. In her research, Michaela uses images of the aurora and other measurements taken by satellites in space to test how well models can predict the aurora. By understanding the response of Earth’s magnetic field and the physical processes that cause the aurora, we can better predict when the aurora might occur and as such prevent damage to technology and essential services on Earth.

An image of Saturn taken using a telescope. The rings of the planet are clearly visible round a dusky yellow and orange globe. The rest of the frame is pitch black

Why does the length of a day on Saturn change over time?

29 April 2022

Nahid Chowdhury (University of Leicester)

The length of a day on Saturn has been changing constantly ever since the first sophisticated proxy measurements were taken by the Voyager I and II spacecraft back in the 1980s and then later by the NASA Cassini spacecraft in the early 2000s. Using ground-based observations of Saturn's infrared northern aurorae, we carried out our own unique experiment to try and detect the hypothesised "twin-vortex" mechanism in the planet's atmosphere that is suggested to drive the changes in Saturn's rotation rate. In this talk, we'll present the results of this experiment as well as a staggering discovery that answered one of the longest standing questions in planetary science.

Speaker bio:

Nahid was born in Oldham but grew up in Leicester which is where he attended primary school all the way through to university, graduating with an MPhys Physics with Astrophysics degree in 2017 before starting his PhD in planetary science, which he is set to finish in 2022. His primary research focus is on the infrared aurorae of the gas giant planets and his work involves observing  the aurorae of Jupiter and Saturn using major ground-based telescopes and then investigating the impact of these emissions on the wider local planetary environments at large. He led the recent study which addressed why Saturn's rotation rate is subject to change over the course of several years. He also supports the foundation year teaching in physics and maths at the University of Leicester and is a keen public outreach enthusiast which led him to holding paid positions at both the Royal Observatory Greenwich in London and the National Space Centre in Leicester.


Exploring the icy moons in our Solar System: could life be out there?

11 February 2022

Dr Vassilia Spathis (University of Kent)

The icy moons in our outer Solar System are postulated to be some of the most likely places to find evidence of life close to Earth. This is largely due to the presence of subsurface oceans, with upcoming missions setting out to search for bio-significant molecules and ingredients for life. In this talk, we will briefly explore some of the icy moons and prebiotic ice chemistry that are of interest to space scientists and the search for life in our Solar System.

Speaker bio:

Dr Vassilia Spathis started as a Forensic Science and Chemistry graduate, before acquiring a PhD in Physics in 2020. She has since been working as a Postdoctoral Research Associate in Space Science and Astrochemistry at the University of Kent investigating whether hypervelocity impacts could be responsible for the synthesis of prebiotic molecules in our Solar System, with a particular focus on the outer Solar System icy moons.

Dark Matter

Dark Matter... How can we search for the invisible?

10 December 2021

Hannah Banks (University of Cambridge)

Take a look around you. Everything that you can see has interacted with the light entering your eyes – that’s what allows you to observe it. However nearly 85% of matter in the Universe doesn’t behave in this way. It can be neither seen nor felt. Whilst this mysterious “Dark Matter” vastly dominates over the visible Universe, it has never actually been detected. In fact, we still do not even know what it is….In this talk we will explore the astrophysical and cosmological phenomena which indicate that there must be more to Universe than what we can see, before turning to how scientists around the world are racing to pin down the nature and properties of this mysterious substance.

Speaker bio:

Hannah Banks is a PhD student in Theoretical Physics at the University of Cambridge where she is researching theories “Beyond-the-Standard Model” of particle physics. At present, she is particularly interested in how Quantum technologies could be used to probe unanswered questions in fundamental physics, such as the nature of Dark Matter. She previously completed an MSci in Physics at Imperial College and has worked as both an explainer and planetarium presenter at the Royal Observatory Greenwich for several years.

A scientist stands in front of the James Webb Space Telescope during testing

How will the Webb Telescope transform our view of the Universe?

12 November 2021

Dr Stephen Wilkins (Head of Astronomy, University of Sussex) 

The James Webb Space Telescope, or Webb, is the long-awaited successor to the Hubble Space Telescope. Like Hubble before it, Webb is an international mission, featuring strong involvement from the UK and Europe. Ultimately thousands of scientists from across the world will use Webb to answer outstanding questions including: when and how did the first stars and galaxies form, and, what do the atmospheres of alien planets contain?

Speaker bio

Born and raised in Yorkshire, Stephen completed his undergraduate studies at the University of Durham before gaining his doctorate from the University of Cambridge. Following a short spell in Oxford, Stephen was appointed a lecturer at the University of Sussex. Today Stephen is a Reader and Head of Astronomy at Sussex.

Artist's interpretation of a gamma ray burst. The black hole drives powerful jets of particles traveling near the speed of light. The jets pierce through the star, emitting X-rays and gamma rays as they stream into space.

Unravelling Gigantic Structures in the Gamma-ray Sky

31 March 2021

Dr Pooja Surajbali (Max Planck Institute for Nuclear Physics) 

The High Altitude Water Cherenkov (HAWC) gamma-ray observatory, located in Mexico, is designed to detect signals generated from the most energetic electromagnetic waves which, in turn, were emitted by sources in the sky. In this talk, Dr Pooja Surajbali will present the development and application of novel data analysis and modelling techniques to observations from HAWC.  She will discuss how she used these data analysis tools to perform blind searches for extended structures in the very high-energy gamma-ray sky which culminated in the discovery of an exciting, previously unseen and mysterious region of gamma-ray emission.

Speaker bio

Dr Pooja Surajbali was born in Mauritius where she studied up to her Bachelor which was in Physics with minor in Astrophysics at the University of Mauritius. In 2014, she was awarded the State of Mauritius Postgraduate Scholarship to do a Masters in Astrophysics at University College London and then proceeded to do her Doctoral studies at the Max Planck Institute for Nuclear Physics (MPIK) in association with the Ruprecht-Karl University of Heidelberg. Her doctoral research involved the development of an array of sophisticated data analysis tools and their application to gamma-ray observations from the HAWC observatory. She is now a full-time postdoctoral researcher at MPIK.


How can we protect Earth from asteroid impacts?

10 February 2021

Lord Dover (University of Kent) 

The dinosaurs didn’t have a space program - but we do. In this talk, Lord Dover - a PhD student researching near-Earth asteroids - will explain the ongoing efforts by scientists and engineers to protect Earth from deadly asteroid impacts. He will describe how astronomers detect and track potentially hazardous asteroids and the technologies we could use to deflect them. Lord will also discuss the recent loss of Arecibo Observatory in the context of planetary defence and look at NASA’s upcoming DART mission.

Speaker bio

Lord is a third year PhD student at the University of Kent researching how Solar radiation drives the physical evolution of small asteroids. He previously studied at the University of Hertfordshire, obtaining a BSc in Astrophysics and an MSc in Astronomy. Lord has also previously worked as a science communicator at Bayfordbury Observatory, where he was a presenter in the UK’s largest mobile planetarium. Most recently, he has been generating 3D computer models of asteroids using data from optical telescopes and planetary radar facilities.


Will we find the perfect Earth-like exoplanet?

27 January 2021

Dr Angelos Tsiaras (University College London)

Today, we have discovered more than 4000 exoplanets – planets that do not belong to our Solar System and are orbiting around other stars. So far, we know that there are all sorts of different exoplanets: rocky or gaseous, small or large, hot or cold, but we don’t know much about them. One of the questions that most of us want to know is if any of these planets is suitable for us to live on it. In his talk, Dr Angelos Tsiaras will discuss what it takes to find a habitable planet other than the Earth, and how close are we in achieving this goal.

Speaker bio

Angelos is an astronomer and physicist, currently working as a senior research fellow at University College London (UCL) and as a part-time astronomer at the Royal Observatory Greenwich. He holds a BSc in Physics from the Aristotle University of Thessaloniki and a PhD in Astronomy from UCL. Angelos has been studying and working in the field of exoplanets for the last ten years, with most of his work being around the characterisation of the atmospheres of exoplanets with the Hubble Space Telescope. More recently, together with his colleagues discovered the atmosphere with water vapour around a habitable-zone exoplanet, K2-18b. Angelos’ expertise is on astronomical data analysis, both with ground-based and spaced-based telescopes, and he is developing user-friendly scientific tools that are used both within and outside academia, as he is strongly supporting Open Science and the collaboration between the public, amateur astronomers and professional astronomers.

Image of Venus, which resembles a smooth white marble ball

Will we find life elsewhere in the Solar System? 18 November 2020

Dr Emily Drabek-Maunder (Royal Observatory Greenwich)

The discovery of phosphine gas in the atmosphere of Venus might just possibly be an indicator that there is some form of life in the clouds of the hottest planet in our Solar System. In this talk, Royal Observatory Greenwich astronomer Emily Drabek-Maunder – who is also a co-author of the key paper about this discovery – explains how astronomers can use telescope observations of gas to search for life beyond the Earth. She will discuss the recent discovery of phosphine in Venus' clouds, what it means and what happens next.

Speaker bio:

Dr Emily Drabek-Maunder is an astrophysicist and Senior Manager of Public Astronomy at the Royal Observatory Greenwich. For the past ten years, she has studied the formation of solar systems using long wavelength telescopes (infrared to radio) located around the world. She obtained her PhD in Physics from the University of Exeter studying the formation of stars and BSc in Physics and Mathematics from Loyola University New Orleans. Emily has previously worked as a researcher at the Fermi National Accelerator Laboratory outside of Chicago, USA, Imperial College London and Cardiff University. She is a part of the research team that recently announced the discovery of phosphine, a possible biosignature, in the atmosphere of Venus.

Main image: Andromeda Galaxy at Arm's Length © Nicolas Lefaudeux, Astronomy Photographer of the Year 2020