[PLS] Allison McCarthy (Boston University)
Date: Tuesday, October 22, 2024 Time: 12:30 - 1:30pm Location: 54-517 | MIT Campus, Cambridge, MA“The Atmospheric Structure and Variability Mechanisms on the Isolated Exoplanet Analog SIMP J0136+0933”
Isolated planetary-mass objects share their mass range with planets but do not orbit a star. They lack the necessary mass to support fusion in their cores and thermally radiate their heat from formation as they cool, primarily at infrared wavelengths. Many isolated planetary-mass objects show variations in their infrared brightness consistent with non-uniform atmospheric features modulated by their rotation. SIMP J013656.5+093347.3 is a rapidly rotating isolated planetary-mass object, and previous infrared monitoring suggests complex atmospheric features rotating in and out of view. First, I will present the results of near-simultaneous ground-based J- and Ks-band multi-wavelength observations of SIMP J013656.5+093347.3. The results from this work suggested that at least two variability mechanisms must be present. Then, I will present the first JWST time-resolved low-resolution spectroscopy from 0.8 – 11 μm of SIMP J013656.5+093347.3 which supports the presence of three specific features in the atmosphere: clouds, hot spots, and changing carbon chemistry. I will show that no single mechanism can explain the variations in the time-resolved spectra. When combined with previous studies of this object indicating patchy clouds and aurorae, these measurements reveal the rich complexity of the atmosphere of SIMP J013656.5+093347.3. Gas giant planets in the solar system, specifically Jupiter and Saturn, also have multiple cloud layers and high-altitude hot spots, suggesting these phenomena are also present in worlds both within and beyond our solar-system.
Planetary Lunch Seminar —
Colloquia topics span the range of research interests of the department’s planetary sciences research program, and the talks are intended to appeal to any graduate students, postdocs, research scientists, and faculty with a background in planetary science. Speakers include members of the MIT community and visitors.
Contact: planetary-org@mit.edu