Jonathan M. Irwin

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A decade ago, the detection of the first transiting extrasolar planet provided a direct constraint on its composition and opened the door to spectroscopic investigations of extrasolar planetary atmospheres. Because such characterization studies are feasible only for transiting systems that are both nearby and for which the planet-to-star radius ratio is(More)
Sh 2-188 is an example of strong interaction between a planetary nebula (PN) and the interstellar medium (ISM). It shows a single arc-like structure, consisting of several filaments, which is postulated to be the result of motion through the ISM. We present new Hα images from the Isaac Newton Telescope Photometric Hα Survey of the Northern Galactic Plane(More)
We report the discovery of WASP-10b, a new transiting extrasolar planet (ESP) discovered by the WASP Consortium and confirmed using NOT FIES and SOPHIE radial velocity data. A 3.09 day period, 29 mmag transit depth, and 2.36 hour duration are derived for WASP-10b using WASP and high precision photometric observations. Simultaneous fitting to the photometric(More)
Most stars become white dwarfs after they have exhausted their nuclear fuel (the Sun will be one such). Between one-quarter and one-half of white dwarfs have elements heavier than helium in their atmospheres, even though these elements ought to sink rapidly into the stellar interiors (unless they are occasionally replenished). The abundance ratios of heavy(More)
The Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) effect is believed to alter the spin states of small bodies in the solar system. However, evidence for the effect has so far been indirect. We report precise optical photometric observations of a small near-Earth asteroid, (54509) 2000 PH5, acquired over 4 years. We found that the asteroid has been(More)
We report on the results of an I-band time-series photometric survey of NGC 2547 using the MPG/ESO 2.2m telescope with WFI, achieving better than 1% photometric precision per data point over 14< ∼ I < ∼ 18. Candidate cluster members were selected from a V vs V − I colour magnitude diagram over 12.5 < V < 24 (covering masses from 0.9 M⊙ down to below the(More)
We present metallicities, radial velocities, and near-infrared (NIR) spectral types for 447 M dwarfs determined from moderate resolution (R ≈ 2000) NIR spectra obtained with the NASA Infrared Telescope Facility (IRTF)/SpeX. These M dwarfs are primarily targets of the MEarth Survey, a transiting planet survey searching for super Earths around mid-to-late M(More)
Using spectroscopic observations and photometric light curves of 238 nearby M dwarfs from the MEarth exoplanet transit survey, we examine the relationships between magnetic activity (quantified by Hα emission), rotation period, and stellar age. Previous attempts to investigate the relationship between magnetic activity and rotation in these stars were(More)
Over the next several years, grid-based photochemical models such as the community multiscale air quality (CMAQ) model, the regional modeling system for aerosols and deposition (REMSAD), the comprehensive air quality model with extensions (CAMx), and other regional models will be used by regulatory agencies in the United States for designing emission(More)