This post was authored by Stephanie Marcus, Science Reference Librarian in the Science, Technology, and Business Division.

The Earth loses hundreds of tons of its atmosphere to space on a daily basis, due to the effects of solar radiation and the solar wind.  Luckily, the Earth has enough atmosphere to last billions of years.  The escaping atmosphere happens mostly at high latitudes, where solar wind-driven energy streams down into the atmosphere to form the aurora.  The energy ionizes, heats, and accelerates the upper atmosphere, ejecting part of it into space.  The processes by which heavier gases like oxygen, which are gravitationally bound, are heated and energized by factors of one hundred or more before reaching escape velocity remain mysterious.  On planets like Mars, these and similar processes are thought to have resulted in the almost total erosion of a once-dense atmosphere.  Since these effects can be critical in determining planetary habitability for other planets around other stars, Earth provides the natural laboratory for their study.

Dr. Douglas Rowland, an astrophysicist in the Space Weather Laboratory of the Heliophysics Division at NASA Goddard Space Flight Center, led the VISIONS-2 (VISualiziing Ion Outflow via Neutral atom Sensing-2) NASA sounding rocket mission, which is part of the multinational Grand Challenge Initiative (GCI)-Cusp project.  The VISIONS-2 was launched from the world’s northernmost town, Ny Ålesund, Norway, 769 miles from the North Pole, and the one inhabited place on Earth where the solar wind has direct access to the atmosphere.

Dr. Rowland will talk about atmospheric escape, his adventures in Norway, and what is being learned from the VISIONS-2 data in his lecture, Exploring Our Escaping Atmosphere: Going above the Top of the World to Watch the Sky, on Thursday, October 17, from 11:30 a.m.-12:30 p.m. in the Madison building’s third floor Pickford Theater.

For inquiries about this program, contact Stephanie Marcus in the Science, Technology & Business Division at 202-707-1192 or [email protected]. Individuals requiring accommodations for this event are requested to submit a request at least five business days in advance by contacting (202) 707-6362 or [email protected].