Suzanne Hawley Named Division Dean for the Natural Sciences at UW

Professor Suzanne Hawley

Robert Stacey, Dean of the University of Washington College of Arts and Sciences, announced that Suzanne Hawley will be the next Divisional Dean for the Natural Sciences.

“I look forward to promoting interdisciplinary studies in my new role,” said Hawley. “The world of big data is upon us. It is essential that our students have the opportunity to engage in world-class research, while also obtaining an integrated arts and sciences education. Scientists need to be excellent writers and communicators, and to understand the broader social and historical context of their work.”

Read more at the source here.

Avoiding “false positives” in the search for living worlds

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Artist rendition (NASA) of Kepler 62e, a super-Earth exoplanet orbiting within the habitable zone of a M dwarf host star.

Recent research has shown that planets orbiting cool stars are potentially susceptible to the abiotic accumulation of oxygen, often considered a key biosignature. A new study led by UW doctoral student Edward Schwieterman and Professor Victoria Meadows has found that these potential “false positives” for life are accompanied by other spectral signatures that would indicate their abiotic origin.  If abiotic oxygen is produced through CO2 photolysis, CO would also be also be observable in transit transmission observations. If the abiotic oxygen is from a history of massive hydrogen escape, the substantial oxygen atmosphere that would remain could be identified by pressure-sensitive O4 features in transmission or reflected light observations. This information can help inform future astronomical biosignature surveys of nearby planetary systems. The paper has been published in the Astrophysical Journal Letters. UW Astronomy graduate students Rodrigo Luger and Giada Arney and VPL researchers Shawn Domagal-Goldman, Drake Deming, Sonny Harman, Amit Misra, and Rory Barnes also contributed.

Black Holes in Vanishing Quasars have Eaten their Fill

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Quasar spectrum overlaid upon an artist’s impression. See video below.

UW astronomy graduate student John Ruan and professor Scott Anderson have discovered distant quasars which have apparently disappeared. This new phenomenon is caused by a shortage in the supply of gas infalling onto the supermassive black holes in the quasars, leading to dramatic dimming of the quasars’ brightness over just a few years. This surprising discovery gives astronomers a real-time view of how black holes in the centers of galaxies grow, and potentially its effects on how galaxies evolve over cosmic time. Read more about the news articles in UW Today and Science.

Grad Applications 2015

Grad applications for UW Astronomy are due December 31, 2015! For official information about the graduate program and structure, click here and here. If you’d like to learn more about our program from the prospective of current grads, see these pages. We seek to achieve scientific rigor and excellence and strive to promote a welcoming environment for people of all gender, race, ethnicity, age, disability, sexual orientation, gender identity or expression, or national origin. When you’re ready to apply, follow detailed instructions on how to do so here.

Autumn Quarter 2015

Autumn Quarter officially starts on Sep 30, 2015! Don’t forget to sign up for classes and register. Review the course catalogue for astronomy here. Late registration fee begins on Sep 30; last day to add/drop courses without a fee is Oct 6. Tuition payment and tuition-related fees are due Oct 16.

Earth observations show how nitrogen may be detected on exoplanets, aiding search for life

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The Earth as seen by the Polychromatic Imaging Camera aboard NASA’s Deep Space Climate Observatory satellite, July 2015 (NASA).

VPL graduate student Edward Schwieterman, professor Victoria Meadows, and researchers Tyler Robinson, Amit Misra, and Shawn Domagal-Goldman have demonstrated that the collisional absorption signature of nitrogen gas can be detected in Earth’s disk-averaged spectrum and have modeled how it would appear on Earth-like exoplanets. Usually, nitrogen is considered an “invisible gas” because it lacks normal spectral features.  Detection of nitrogen would provide a means to characterize the bulk atmosphere of potentially habitable exoplanets and constrain the likelihood of oxygen production by non-living processes. The paper has been published in The Astrophysical Journal here. Read more about the news article at UW Today.

UW astronomer, students report irregularities in ‘rare, exotic’ binary system

The galaxy NGC 300, home to the unusual binary system Binder and her colleagues studied. The spiral galaxy is over 6 million light years away. NASA/JPL-Caltech/OCIW

UW astronomers Breanna Binder and Ben Williams, along with the help of undergraduates Jacob Gross and Daniel Simons, were recently reminded that the diplomatic axiom to “trust, but verify” also applies to scientific inquiry when they analyzed fresh data from a distant galaxy. As they reported in July in the Monthly Notices of the Royal Astronomical Society, a puzzling stellar phenomenon may not be what other astronomers had reported. Read more at UW Today.

 

“Upside-down planet” reveals new method for studying binary star systems

An image of the Sun used to simulate what the sun-like star in a self-lensing binary star system might look like. NASA.

Working with UW astronomer Eric Agol, doctoral student Ethan Kruse has confirmed the first “self-lensing” binary star system — one in which the mass of the closer star can be measured by how powerfully it magnifies light from its more distant companion star. Though our sun stands alone, about 40 percent of similar stars are in binary (two-star) or multi-star systems, orbiting their companions in a gravitational dance. Read more at Astronomy Magazine.

 

‘Dimer molecules’ aid study of exoplanet pressure, hunt for life

An artist’s concept of an exoplanet, or planet outside the solar system.NASA

Astronomers at the University of Washington have developed a new method of gauging the atmospheric pressure of exoplanets, or worlds beyond the solar system, by looking for a certain type of molecule. And if there is life out in space, scientists may one day use this same technique to detect its biosignature — the telltale chemical signs of its presence — in the atmosphere of an alien world. The method, devised by Amit Misra, a UW astronomy doctoral student, and co-authors, involves computer simulations of the chemistry of Earth’s own atmosphere that isolate what are called “dimer molecules” — pairs of molecules that tend to form at high pressures and densities in a planet’s atmosphere. Read more at UW Today.

UW astronomer Eric Agol’s seven-planet system part of major NASA discovery

An artist’s illustration of multiple-transiting planet systems. The planets eclipse or transit their host star from the vantage point of the observer.

University of Washington astronomer Eric Agol played a key role in the windfall of 715 new exoplanets announced by NASA Feb. 26. Agol was on a team that found seven of those worlds, all in orbit around the same star, Kepler-90. It’s the first planetary system with seven planets seen to transit, or cross in front of their host star. Read more at UW Today.