Qier An (安琪儿)

I am a Ph.D. candidate in the William H. Miller III Department of Physics & Astronomy at Johns Hopkins University, advised by Dr. Timothy Brandt at STScI and Prof. Kevin Schlaufman. I study the detection and characterization of substellar objects by combining precision astrometry, radial-velocity measurements, and direct-imaging data. My work contributed to observing programs such as NASA Keck SMS and the SCExAO Direct Imaging Survey, and involved processing data from Gaia, Hipparcos, and ground-based AO systems. Before JHU, I completed my M.A. in Physics at the University of California, Santa Barbara in 2024, where I worked with Dr. Timothy Brandt on identifying and characterizing substellar companions.

I earned my B.S. degrees in Engineering Physics and in Mathematics & Astronomy from the University of Illinois Urbana–Champaign in December 2020, graduating with Highest Honors. My early research was in condensed-matter experiment and biophysics computation, including a 2023 publication on the channel capacity of the ribosome.

Email: qan4@jh.edu

News

Dec 4, 2025

Our collaboration, OASIS, has discovered two substellar companions using high-contrast imaging and Hipparcos–Gaia astrometry. Read the press release here.

Oct 21, 2025

We identifyied a brown dwarf orbiting a red dwarf, by first time applying Gaia acceleration in orbit fit, check press release here.

Sep 26, 2025

Our paper “Orbits and Masses for 156 Companions from Combined Astrometry and Radial Velocities, and a Validation of Gaia Non-single-star Solutions” was published in ApJS.

Dec 12, 2024

Our paper “Significant mutual inclinations between the stellar spin and the orbits of both planets in the HAT-P-11 system” was published in AJ.