Gravity Group Lunch Seminar | Sarah Marie Bruno, "The projected impact of commercial satellite constellations on ground-based astronomy" & Roman Kolevatov, "The DMRadio Experiment at Princeton"

Fri, Apr 23, 2021, 12:00 pm
via Zoom

Sarah Marie Bruno, Princeton University 
"The projected impact of commercial satellite constellations on ground-based astronomy"

The ongoing commercialization of satellite technology is leading to the ubiquity of privately owned and operated satellite spacecraft in low-Earth orbits. These satellites can be used for data collection for a variety of commercially viable applications including low-cost global internet access, time-share for academic researchers in fields such as astronomy and climate change, and access for government agencies for various applications. As of May 2020, there were an estimated 2200 satellites in low-Earth orbits, a number that has grown within the past year. Several commercial companies plan to launch mega-constellations of small satellites for high-speed broadband satellite internet, including SpaceX's Starlink project, which will launch 42,000 satellites. While there are many projected societal benefits of the upcoming commercial satellite initiatives, increasing satellite prevalence will undoubtedly impact ground-based astronomy. Some satellites may transmit in low-frequency bands that interfere with radio astronomy. Additionally, satellites in certain orbits may reflect sunlight, impeding the ability of ground-based telescopes to observe in the visible spectrum. The future of ground-based projects is uncertain. I will describe the expected impact of commercial satellites on ground-based astronomy and highlight several proposals for mitigating this effect.

Roman Kolevatov, Princeton University 
"The DMRadio Experiment at Princeton"

Axions are hypothetical particles initially introduced to solve the strong CP problem of QCD. Simultaneously, axions are a compelling dark matter candidate, which has resulted in the proposal of detectors to search for them. The Dark Matter Radio experiment is a QCD axion, and axion-like particles search in a substantive range of masses from peV to micro-eV. We will discuss one of the efforts of the DMRadio collaboration at Princeton, which involves designing and testing a high-Q (>10^6) lumped-element resonator operating at cryogenic temperatures to enhance the axion signal.