EH102, 1/F, Eliot Hall, Main Campus, HKU
November 17, 2026 (Tuesday)
1:30 pm – 2:30 pm
Our Solar System sits in a million-Kelvin, low-density bubble that is about 100-200 pc across, expanded by multiple supernovae over the past ~20 Myr. I will review our current knowledge of this Local Hot Bubble, primarily from X-ray observations, but also combine multiple lines of evidence, including radioisotopes found on Earth, to paint a coherent picture of this local region.
NewAthena, the next-generation flagship X-ray mission, will feature a micro-calorimeter that will resolve many important diagnostic lines in the soft X-ray band. I will demonstrate how NewAthena, or more generally, eV-level spectral resolution, can answer long-standing questions about the Local Hot Bubble by generating and analysing synthetic NewAthena observations.
Dr. Michael Yeung is a postdoctoral researcher at the Max Planck Institute for Extraterrestrial Physics in Garching, Germany. He received his PhD from the same institute in 2025, where he dissected the soft X-ray background observed by eROSITA into its physical components, with particular attention to solar wind charge exchange in the heliosphere, the local interstellar medium, and the eROSITA bubbles.
Before moving to Germany, he earned his MPhil and BSc degrees at HKU under Prof. Jeremy Lim. At HKU, he combined Hubble Space Telescope and Keck Observatory data to study star formation and stellar populations in brightest cluster galaxies, and his MPhil thesis reconstructed the velocity structure of strongly lensed galaxies observed with ALMA. His current work continues to explore the diffuse X-ray sky, superbubbles and their links to the circumgalactic environment.
Anyone interested is welcome to attend in person or via Zoom:
https://hku.zoom.us/j/96472971072?pwd=uoTCtn45823IaLEyIkyrQvvZPjyt0C.1
Meeting ID: 964 7297 1072 Password: 410133