Artist’s conception of a "Y dwarf,” the coldest star-like body known, with temperatures that can be even cooler than the human body. Y dwarfs are brown dwarfs—celestial objects that begin their lives like stars, but never accumulate enough mass to sustain nuclear fusion and shine like a regular star. Instead, they cool and fade with time, giving off most of their light in infrared wavelengths.

Emily Rice, assistant professor of engineering science and physics at the College of Staten Island, City University of New York, will highlight brown dwarf stars in the Vernon Memorial Lecture on April 27 at UD.

April 27: Cooler than the coolest stars

Article by Tracey Bryant April 04, 2017

Vernon Memorial Lecture delves into brown dwarfs

Growing ever-dimmer as they cool, brown dwarf stars are probably the most numerous celestial objects in the sky — and certainly among the most mysterious.

“Brown dwarfs teeter on the boundary line between stars and planets,” says Judi Provencal, director of the Delaware Asteroseismic Research Center (DARC) at the University of Delaware. “They form like stars do from clouds of gas and dust, but lack the mass to become true members of the stellar family. As they cool and fade, brown dwarfs resemble gas giant planets like our own Jupiter.”

On Thursday, April 27, starting at 7:30 p.m. at UD’s Clayton Hall Conference Center, DARC will welcome guest astronomer Emily Rice, who will present “Brown Dwarfs: Cooler Than the Coolest Stars,” the spring edition of the Harcourt C. (Ace) Vernon Memorial Lecture. Rice will explain how brown dwarfs form and how they work. She also will delve into how studying the atmospheres of brown dwarfs, particularly “young” ones less than 100 million years old, will expand our understanding of gas giant planets that orbit stars other than the sun.

Rice is an assistant professor at the College of Staten Island, City University of New York. She also is a research associate in astrophysics at the American Museum of Natural History and co-leader of the Brown Dwarfs in New York City (BDNYC) research group.

The Vernon Memorial Lecture is free and open to the public. Advance registration is requested to ensure adequate seating.

The lecture is sponsored by the Delaware Asteroseismic Research Center, Mount Cuba Astronomical Foundation and Mount Cuba Astronomical Observatory in Greenville, Delaware.

Harcourt C. (Ace) Vernon (1907–78), after whom the lecture is named, was one of the observatory’s founders and the first chairman of its board of trustees.