“Twinkle, Twinkle, New-Born Star”, featured in Science Update of the Harvard-Smithsonian Center for Astrophysics, December 2014. This one is about our findings about young stars and their planet-forming disks, published in Günther et al. (2014). It turns out that practically all disk-bearing stars are variable in brightness, especially as shown in this study in the mid-infrared, where disks had previously assumed to be rather quiescent. However, our work shows that the mid-disk probed by our observations is a highly dynamic and variable place.
Günther, H. M.; Cody, A. M.; Covey, K. R.; Hillenbrand, L. A.; Plavchan, P.; Poppenhaeger, K.; Rebull, L. M.; Stauffer, J. R.; Wolk, S. J.; Allen, L.; Bayo, A.; Gutermuth, R. A.; Hora, J. L.; Meng, H. Y. A.; Morales-Calderón, M.; Parks, J. R.; Song, Inseok: “YSOVAR: Mid-infrared Variability in the Star-forming Region Lynds 1688”, The Astronomical Journal, Volume 148, Issue 6, article id. 122, 20 pp. (2014).
“Harsh space weather may doom potential life on red-dwarf planets”, featured in press release at the 224th meeting of the American Astronomical Society, June 2014. This one is about our work on atmospheres of planets in habitable zones around M dwarfs. We find that the magnetic shielding of exoplanets is likely not strong enough to protect the exoplanetary atmosphere from being eroded by the stellar wind over time, meaning that many old exoplanets in M dwarf systems may have lost large parts of their atmosphere.
Cohen, O.; Drake, J. J.; Glocer, A.; Garraffo, C.; Poppenhaeger, K.; Bell, J. M.; Ridley, A. J.; Gombosi, T. I.: “Magnetospheric Structure and Atmospheric Joule Heating of Habitable Planets Orbiting M-dwarf Stars”, The Astrophysical Journal, Volume 790, Issue 1, article id. 57, 13 pp. (2014).
“Big planets could alter star rotation”, featured in Nature Research Highlights May 2014. This one is about our work on stellar rotation in exoplanet systems. We find for several systems that the close-in exoplanet has likely altered the evolution of the stellar rotation by depositing angular momentum from the planetary orbit into the stellar spin.
Poppenhaeger, K.; Wolk, S. J.: “Indications for an influence of hot Jupiters on the rotation and activity of their host stars”, Astronomy & Astrophysics, Volume 565, id.L1, 5 pp. (2014).
“NASA’s Chandra Sees Eclipsing Planet in X-rays for First Time”, featured in NASA press release July 2013. This one is about our observations leading to the first detection of an exoplanetary atmosphere in the X-ray band. We find that the exoplanetary atmosphere of this Hot Jupiter is extended and dense enough to be X-ray opaque out to altitudes of 1.7 optical radii.
Poppenhaeger, K.; Schmitt, J. H. M. M.; Wolk, S. J.: “Transit Observations of the Hot Jupiter HD 189733b at X-Ray Wavelengths”, The Astrophysical Journal, Volume 773, Issue 1, article id. 62, 16 pp. (2013).
“Astronomy: No planetary X-ray pull”, featured in Nature Research Highlights July 2010. This one is about our research on the coronal emission of planet-hosting stars in the solar neighborhood. We find that in the full sample of the observed planet-hosting stars there is no significant X-ray enhancement of the star that can be traced back to a gradual star-planet interaction effect.
Poppenhaeger, K.; Robrade, J.; Schmitt, J. H. M. M.: “Coronal properties of planet-bearing stars”, Astronomy and Astrophysics, Volume 515, id.A98, 9 pp. (2010).