Astronomy with X-rays: How, Where, and Most Importantly Why?
Dr. Randall Smith
Sunday, September 12, 2021
7:30 PM to 9:00 PM EST
Monthly Meeting – Public Invited
X-ray astronomy began in 1962 when Riccardo Giacconi and his team launched a sounding rocket with an X-ray detector designed to look at the Moon – and unexpectedly found a far brighter source in Scorpius they called Sco X-1. Generating X-rays requires energetic processes – big explosions, strong gravitational fields, and collisions of fast or even relativistic particles. Observing them thus reveals just what’s going on in these exciting regions of space. We can also take advantage of the penetrative properties of X-rays – just as we do to look at a broken bone here on Earth – to study material between the source and us as the X-rays are absorbed and scattered by gas and dust. Since 1962 the field has exploded, with a range of new detectors as well as techniques to make high-quality X-ray “mirrors.” This talk will be a survey of the field, highlighting important discoveries as well as the instrumentation required, as well as discussing where we’re going next.
An astrophysicist at the Harvard-Smithsonian Center for Astrophysics, Randall Smith primarily works in high-energy astrophysics. He is involved with multiple X-ray observatories, both current and planned; his personal research focuses on the interstellar medium and on maintaining an atomic database that is used throughout the field to model the spectra of hot collisional plasmas. He earned his PhD in 1997 at the University of Wisconsin-Madison, working with the Space Physics group and advisor, Dr. Don Cox.