Stan Metchev, Professor and Canada Research Chair

Brown dwarfs---giant planets' more massive kin---offer a convenient probe of exoplanetary atmospheres. With sizes and temperatures similar to those of known exoplanets, the atmospheres of brown dwarfs are governed by comparable dynamics, and exhibit similar characteristics: clouds, zonal winds, and storms. Multi-wavelength photometric and spectroscopic monitoring of brown dwarfs can reveal the vertical and longitudinal temperature structure of storms in substellar atmospheres. Such observations have also been the first ones to probe the atmospheric dynamics of extrasolar planets. Much like low-mass stars, brown dwarfs may also host planetary systems in their own right. These are expected to contain mostly rocky, potentially Earth-like exoplanets. The discovery of rocky planets around low-mass stars and brown dwarfs is a top priority in Dr. Metchev's research, and the subject of the POET micro-satellite mission, in development with the Canadian Space Agency.

Trans-Neptunian objects are the leftover debris from the formation of our own solar system. The largest of these (Pluto, Charon, Quaoar, Eris) are over 1000 km in size and are well-known. No objects smaller than 10 km are known as they are too small to see in reflected or thermal emission even with the most sensitive telescopes. Yet, these small kilometre-sized TNOs account for the vast majority of objects in the outer solar system. Their abundance and size distribution carry critical information about the formation history of the solar system. A novel technique, which uses serendipitous stellar occultations as an alternative way to detect small TNOs, is being developed at several observatories world-wide. Dr. Metchev's r obotic Colibri Telescope Array represents one of these novel pursuits. Using very rapid (40 frames per second) imaging, the 50 cm Colibri telescopes are designed to capture the <0.2 sec durations when a distant star's light is temporarily dimmed by a kilometre-sized TNO passing in the foreground.

1. Miles-Páez, P. A., Metchev, S. A., and George, B., “The photometric periods of rapidly rotating field ultra-cool dwarfs”, Monthly Notices of the Royal Astronomical Society, vol. 521, no. 1, pp. 952–968, 2023. doi:10.1093/mnras/stad273.
2. Miles, B. et al., "The JWST Early-release Science Program for Direct Observations of Exoplanetary Systems II: A 1 to 20 μm Spectrum of the Planetary-mass Companion VHS 1256-1257 b", The Astrophysical Journal Letters, vol. 946, 1, id.L6, 19 pp., 2023, doi:10.3847/2041-8213/acb04a.
3. Mazur, M. J., et al. “The Colibri telescope array for KBO detection through serendipitous stellar occultations: A technical description”, Frontiers in Astronomy and Space Sciences, vol. 9, 2022. doi:10.3389/fspas.2022.929573.
4. Tannock, M. E., et al. “A 1.46-2.48 μm spectroscopic atlas of a T6 dwarf (1060 K) atmosphere with IGRINS: first detections of H2S and H2, and verification of H2O, CH4, and NH3 line lists”, Monthly Notices of the Royal Astronomical Society, vol. 514, no. 3, pp. 3160–3178, 2022. doi:10.1093/mnras/stac1412.
5. Suárez, G. and Metchev, S., “Ultracool dwarfs observed with the Spitzer infrared spectrograph - II. Emergence and sedimentation of silicate clouds in L dwarfs, and analysis of the full M5-T9 field dwarf spectroscopic sample”, Monthly Notices of the Royal Astronomical Society, vol. 513, no. 4, pp. 5701–5726, 2022. doi:10.1093/mnras/stac1205.
6. Hinkley, S. et al., "The JWST Early Release Science Program for the Direct Imaging and Spectroscopy of Exoplanetary Systems", Publications of the Astronomical Society of the Pacific, vol. 134, 1039, id.095003, 20 pp., 2022, doi:10.1088/1538-3873/ac77bd.

[ Complete Publications List (Scopus)]

[ Complete Publications List (NASA ADS)]

Undergraduate:
Physics 1402: Physics for Engineering Students II
Astronomy 2801: Obsering the Stars
Astronomy 2021: Life in the Universe
Astronomy 2232: Sun, Earth, and Planets

Graduate:
Astronomy 9610: Fundamentals of Astrophysics
Astronomy 9305: Stellar Photospheres
Astronomy 9203: Formation of Planetary Systems

• Canada Research Chair (Tier 2), 2014-2023
• Western University Faculty of Science Distinguished Research Professor, 2018-2019
• PI of 873-hour Spitzer Space Telescope Exploration Science Program GO 80179:"Weather on Other Worlds: A Survey of Cloud-Induced Variability in Brown Dwarfs",2011-present
• PI of NASA Astrophysics & Data Analysis award 10-ADAP10-0130:"Database Cross-Correlation at Scale: A Complete Census of Cool and Peculiar Brown Dwarfs in the 2MASS/SDSS Overlap", 2011-present
• PI of joint Spitzer/Hubble Space Telescope program Spitzer-GO 40489 (19 hrs) / HST-GO 11304 (1 orbit):"The L/T Transition in the Photospheres of Young Sub-Stellar Companions", 2007-2011
• PI of 44-orbit Hubble Space Telescope program GO 10849, "Imaging Scattered Light from Debris Disks Discovered by Spitzer around 21 Sun-like Stars", 2006-2009
• PI of Spitzer Space Telescope Fellowship award "Circumstellar Disks and Sub-Stellar Objects",2005-2008
• Co-PI of NASA Origins of Solar Systems award 11-OSS11-0073:“High Contrast Observations Close to Stars with Vortex Coronagraphy”,2012-present
• Co-PI of 1144-hour Spitzer Space Telescope Exploration Science Program GO 90063: "Extrasolar Storms: The Physics and Chemistry of Evolving Cloud Structures in Brown Dwarf Atmospheres", 2012-present
• PI or Co-PI on approximately 40 nights of observing time on 2-10 m ground-based telescope facilities annually.

• TMT International Observatory Science Advisory Committee member, 2017-present (Canadian Co-Chair: 2023-present)
• Association of Canadian Universities for Research in Astronomy Board of Management member and Western representative to the Institutional Council, 2020-2023
• CASCA/ACURA/TMT Advisory Committee member, 2017-present
• Joint Committee for Space Astronomy member 2022-present (Chair: 2023-present).
• Current collaborations with postdocs and students:Aren Heinze: SBU postdoc since 2011 (PhD 2007, U Arizona)Rahul Patel: SBU PhD student since 2009Kendra Kellogg: SBU MSc student since 2011 -> Western PhD student since 2013Matthew Wahl: SBU class of 2011, SBU MSc student since 2012Joseph Trollo: SBU class of 2012 -> Western MSc student since 2013
• Past collaborations with postdocs and students:Kerstin Geissler: postdoc 2009-2011 (PhD 2009, Heidelberg)Stephanie Zajac: SBU MSI student 2011-2012, now continuing MSI at SBUMichael McElwain: PhD 2007, UCLA; now Research Astronomer at NASA Goddard SFCShannon Hicks: SBU class of 2012, now Western MSc student since 2013Owen Vail: SBU class of 2012, now PhD student at Georgia TechJustin Bird: SBU class of 2012, now PhD student at Drexel UAmanda White: REU summer student 2011, as of 2012 - Research Aide at AMNHAlfonse Pharm: UCLA class of 2008, now PhD student at Indiana-Purdue IndianapolisTiffany Meshkat: UCLA class of 2009, now PhD student at Leiden UNaoki Eto: SBU Simons Summer Research Fellow in 2010, now BSc student at CaltechJoshua Golub: summer research student in 2010, now BSc student at Binghamton U
• Conference organizing committee member:* Splinter Session on "Clouds in Brown Dwarfs and Giant Planets" during the Cool Stars 17 international conference, June 24-29 in Barcelona, Spain* New York Astronomical Society Meeting, April 20-21, 2012, Stony Brook, NY* Tri-State Astronomy Meeting, October 2010 and 2012, New York, NY
• Elected member of the New York Astronomy Consortium Board of Directors
• Member of the Spitzer Space Telescope Time Allocation Committee, of Spitzer and Hubble Space Telescope review panels, and of numerous NSF, NASA, and NOAO proposal review panels.
• Referee for Science, ApJ, AJ, A&A, Astron. Nachr.
• Outreach through annual public talks for the SBU Astronomy Open Night series and for the SBU Alumni Association, visits to local K-12 schools and astronomy clubs, interviews with the press.
• Founding faculty mentor for the SBU undergraduate Astronomy Club