Joint IAS Princeton University Astrophysics Colloquium

New and improved observational facilities are sampling the night sky with unprecedented temporal cadence and sensitivity across the electromagnetic spectrum. This exercise led to the discovery of new types of astronomical transients and...

Red supergiants (RSGs) are the helium-fusing descendants of moderately massive (10-25Mo) stars. As the coldest and largest (in physical size) members of the massive star population, these evolved stars serve as ideal "magnifying glasses" for...

Several lines of evidence, both theoretical and observational, indicate that additional planets in the outer solar system remain to be discovered. Most recently, attention has been focused on 'Planet Nine',a few Earth mass planet with a moderate...

The observation of mergers of black holes and neutron stars has established gravitational-wave astronomy as powerful tool to understand the Universe. After a brief introduction to gravitational waves and how the detectors work, I will discuss the...

The cosmic microwave background (CMB) research told us a remarkable story: the structure we see in our Universe such as galaxies, stars, planets, and eventually ourselves originated from tiny quantum fluctuations generated in the early Universe...

Over 30 black hole mergers have been found by gravitational wave detectors in recent years, begging the questions, "So What?" and "Is that all??". In this talk I will outline a few, low-hanging, astrophysical/cosmological fruit, as well as 3...

The center of the Milky Way hosts the closest supermassive black hole and nuclear star cluster to the Earth, offering us the opportunity to study the physics of supermassive black holes and their environment at a level of detail not possible...

It has been nearly 100 years since the "Great Debate," where Heber Curtis correctly argued that Thomas Wright's 1750 ideas about our Milky Way being one of many "galaxies," each a flattish disk of a multitude of stars, was correct. Since then...

The Event Horizon Telescope (EHT) is an international collaboration to observe black holes at horizon-scale resolution. The EHT uses the technique of very long baseline interferometry (VLBI) and submillimeter telescopes all over the globe to perform...

In hundreds of known cases, "gravitational lenses” deflect, distort, and magnify images of galaxies behind them. Lensing can magnify galaxies by factors of 10--100 times, transforming them from objects we can barely detect to bright objects we can...