Astrophysics & Planetary Sciences Colloquium

TBA

Time-domain astronomy is entering a new era. With JWST, we can now discover and study supernovae in the early universe, while the Rubin Observatory and the Nancy Grace Roman Space Telescope will find rare transients across wide areas and in unprecedented numbers. These complementary facilities are transforming the transient sky into a laboratory for precision astrophysics and cosmology. In this talk, I will show how these observations are opening new ways to study cosmic expansion and probe the physics of the early universe.

As exoplanet science moves towards bigger, noisier datasets, smaller signals, and more complicated physical models, statistical inference is becoming more and more essential.

Extreme precision radial velocity (EPRV) measurements, capable of capturing signals with an amplitude of just 10-30 cm/s, are needed to uncover low-mass planets and inform planet formation scenarios, calculate planetary interior composition, and constrain atmospheric models.  This need has given rise to innovation in precision spectroscopy at all levels--from the instrumentation to the extraction software through to the astrophysics guiding the final derived RV measurements.

The LCDM cosmological model of our universe has proven remarkably robust against observations spanning billions of years of cosmic evolution. Yet, there are tantalizing hints of new physics that require measuring ever fainter signals with exquisite systematic control. Simultaneously, rapid progress in recent years has been made towards engineering and manipulating quantum systems for computing, networking, and sensing applications, enabling a fundamentally new handle on building measurement tools to study these big questions.

Following in the tradition of other NASA missions like Hubble and the James Webb Space Telescope, the Habitable Worlds Observatory (HWO) is a future NASA FUV-NIR flagship that will revolutionize multiple areas of astrophysics. A challenging next frontier of astronomy and planetary science is to directly image temperate Earth-sized in planets in the habitable zones of Sun-like stars, measure their spectra, and search them for signs of life. HWO will be the first observatory designed to tackle the question “Are we alone?”.

Remote sensing of the universe, including Earth and its atmosphere, largely relies on extracting information from photons/electromagnetic waves. To optimize information extraction, instruments and data analysis have to be looked at as a system. The colloquium will highlight examples of this systems approach to optical instrumentation that I have been involved in over the past few decades.

Hypothesized in the 1960s with the first evidence in the 1990s, the origin, quantity, and distribution of water on the Moon – and other airless bodies – is one of the most exciting questions in planetary sciences. Where did it come from? How much is there? What processes at what rates control the modern day distribution? And where *exactly* is the water? Fine-scale spatial knowledge of distribution is needed so that we can send landed missions to measure and sample for textures, elements, the presence of other volatiles, and isotopes to answer the questions above.

I will discuss NASA's Lucy mission, which is the first reconnaissance of the Jupiter Trojan asteroids. Asteroids are the leftovers from the age of planet formation. But, unlike the planets themselves, they have remained relatively unchanged since they formed. As a result, they hold vital clues to how our Solar System formed and evolved, and thus can be considered the fossils of planet formation. Lucy will visit eight of these important objects between 2027 and 2033.