Dr Ben Montet is a Scientia Associate Professor at UNSW Sydney. He completed his PhD in astrophysics at Caltech and was a Carl Sagan Fellow at the University of Chicago. Dr Montet is a leading exoplanet researcher who uses data from missions like NASA’s Kepler and TESS to discover and study planets beyond our Solar System, uncovering the diversity of planetary systems across our galaxy.

In our conversation, we explore how astronomers detect planets using tiny dips in starlight, and how missions like Kepler and TESS have revolutionised exoplanet discovery. We also discuss his research on a “hot Jupiter” that revealed a hidden companion planet, challenging current models of planetary systems.

We then look at how stars influence whether life is possible, from flares to magnetic activity, and how machine learning is helping uncover new discoveries in massive datasets. Finally, Dr Montet shares his journey into astronomy and advice for students, emphasising curiosity, coding, and taking initiative early.

In this episode of Astrophysics for All, I speak with Dr Caroline Foster, an observational astronomer at UNSW Sydney who studies how galaxies form, grow, and evolve over billions of years.

We explore how astronomers use light to measure the motions and chemistry of stars, how galaxies grow through mergers and star formation, and why some galaxies gradually stop rotating as they age. Dr Foster also explains how globular clusters—ancient, tightly packed groups of stars—act like cosmic fossils that help astronomers uncover the hidden histories of galaxies.

Dr Foster shares how she first became interested in physics and offers advice for students who want to pursue astronomy, highlighting curiosity, mathematics, and the excitement of exploring the biggest questions about the universe.

What if everything we can see in the universe—stars, planets, galaxies, and even ourselves—makes up less than 5% of reality?

In this episode of Astrophysics for All, I sit down with Professor Geraint Lewis, a cosmologist at the Sydney Institute for Astronomy, to explore the invisible universe. Originally from Wales, Professor Lewis completed his undergraduate degree at the University of London and went on to earn his PhD in astrophysics from the University of Cambridge’s Institute of Astronomy. He has worked at research institutions in the United States and Canada before joining the University of Sydney, where he now leads the Gravitational Astrophysics Group.

Although everything we can see—from stars to galaxies to ourselves—makes up less than 5% of the cosmos, the rest is dominated by mysterious dark matter and dark energy that scientists are still struggling to understand.

Professor Lewis explains how astronomers use gravitational lensing to map invisible matter, how galaxies grow by tearing apart smaller ones in a process known as galactic cannibalism, and why studying these phenomena can reveal the hidden structure of the universe. Along the way, Professor Lewis shares what life as a cosmologist looks like and offers practical advice for students curious about pursuing physics and astrophysics.