Dr. Eliot Halley Vrijmoet

VRY-MOOT (he/him)

Education/Research Postdoc Fellow
of the Five College Astronomy Department

Department of Astronomy
Smith College
Northampton, MA 01063

Office: McConnell 410A at Smith
(LGRT 680 at UMass)

E-mail: evrijmoet@smith.edu @eliothalley

Eliot standing outside with coffee. — *Photo by Leonardo Paredes*

Eliot standing next to a tall building, with coffee. — *Photo by Leonardo Paredes*

(updated 28 January 2026)

ORCiD

My work on ADS ADS logo

(refereed list)

My Research Life

Astrometry of M dwarf binaries

My favorite things are low-mass stars with companions (planets, brown dwarfs, other stars).

Which orbits tend to occur? Which orbits tend not to occur?
What are the distributions of orbital parameters for M dwarf companions?
What can this tell us about the physics of star formation?
What can this tell us about where to look for planets?

I am extensively experienced with ground-based astrometry at RECONS. This includes:

Observing procedures for high-quality astrometric data. (trained at CTIO 0.9m)
Data reduction for >400 systems, with focus on careful frame selection and centroiding.
Completing a comprehensive update of RECONS data pipeline, translating it from Bash+IRAF to Python.
Fitting orbits of unresolved companions using MCMC and least-squares techniques.

My PhD advisor, & RECONS fearless leader:
Todd J Henry

RECONS first mate (& my honorary advisor):
Wei-Chun Jao

Astrometry papers:

Vrijmoet et al. 2020 compared RECONS astrometry to Gaia DR2 to identify unresolved binaries based on their astrometric fits.

The next paper (in prep for 2026) will present orbits of ~30 M dwarf binaries from RECONS astrometry.

Speckle papers:

Vrijmoet et al. 2022 presented the first 1.5 years of my M dwarf SOAR speckle campaign.

This speckle interferometry program at SOAR mapped the motions of ~225 M dwarf multiples, many of which were selected from Gaia based on Vrijmoet+ 2020.

Vrijmoet et al. 2026 presented 54 orbits of M dwarfs from the SOAR speckle program.

SMARTS 0.9m telescope at CTIO, where RECONS takes astrometry
(and you could, too! +excellent telescope for students)

Another useful list of links for the SMARTS 0.9m & 1.5m