Astrophysics Seminars

This informal seminar will highlight results obtained recently with the transformational instruments MUSE and GRAVITY on ESO’s Very Large Telescope at Paranal. For MUSE, the focus will be on an ongoing study of the internal dynamics, stellar...

The Event Horizon Telescope recently revealed the first picture of the black-hole shadow in the center of the M87 galaxy. I will discuss the technological and theoretical advances during the last decade that led to this result. I will then focus on...

State-of-the-art local and primordial measurements of the Hubble constant (H0) are currently in tension at the 4.4 sigma level. New physics and systematic errors have been invoked as potential explanations. I will discuss two new, independent...

There is now ample evidence of large quantities of planetesimal material present in orbits extending outwards from Jupiter and beyond. Several research groups have shown that as much as 15% of such material currently in orbits residing between...

The alpha Centauri system contains the Solar System’s closest stellar neighbors. If an earthlike planet is present in the system, it could in principle be detected using a small space-based telescope. As alpha Centauri is billions of years old...

From gas-poor Earths to gas-rich Jupiters, planets come in a variety of sizes. I will describe the physics behind the diversity of exoplanets---how the core and gas assembly processes give rise to the observed distribution of radii and orbital...

Connecting planetary systems at different stages of stellar evolution helps us understand their formation, evolution and fate, and provides us with exclusive and crucial insights about their dynamics and chemistry. Post-main-sequence stars -- white...

Many aspects of the early universe are currently probed through the cosmic microwave background. Due to theoretical developments and an increase in survey sensitivity, these measurements can now be complemented by large-scale structure observations...

Accretion onto black holes probably powers bright astrophysical sources such as active galactic nuclei, some stellar-mass x-ray sources, gamma-ray bursts, and relativistic radio jets. I will survey developments in the theory of black hole accretion...