Surveys of the Stars

For April 17, 2019        
Hi WN@TL Fans,
Last week’s photo of a black hole required a sustained stare by 8 different telescopes at 8 different locations across the globe focussed on a single point a bazillion miles away.  This is a many-eyed approach of Argus.  Then the petabytes of data had to be crunched and clarified to get the ring of fire image.  
 
At the other end of the astronomical spectrum from the sustained stare is the wide-ranging scan across the heavens by a single, spectacular scope.  This is a more cyclopean approach of a survey.  
 
I note that a survey can be a look-see, where one takes a quick look around. But if you’re a surveyor, you’re more than taking a look:  you’re systematically taking measurements to record the key points on the landscape and writing the measurements in your surveyor’s book.  While land surveyors running with transits and tapes did not take pictures, astronomers surveying the skies sometimes do.
 
This week (April 17) Keith Bechtol of Physics and Ellen Bechtol of the Large Synoptic Survey Telescope take us to the ends of the Earth to show how researchers use a range of observatories to help us get out-of-this-world insights into stars, energy, particles, matter, and other stuff that matters.
 
The title of their talk is “The Big Picture:  Science & Public Outreach with Astronomical Surveys.”  The observatories include UW-Madison’s IceCUBE Neutrino Observatory at the South Pole and the Large Synoptic Survey Telescope in Chile. 
Here’s how Keith and Ellen describe their talk:
 
The goal of astronomical surveys is to map as much of the sky as possible as quickly as possible. Rather than starting from a specific set of pre-defined targets for detailed study, astronomical surveys represent a statistical census of the cosmos. 
 
A confluence of technologies, including large-aperture and wide field-of-view telescopes, CCD cameras, and ever growing computational power, have motivated increasingly ambitious surveys that combine depth, wide areal coverage, and high observing cadence. 
 
For example, the Large Synoptic Survey Telescope (LSST), now under construction in Chile, will image the entire southern sky nearly a thousand times over the next decade. LSST will catalog more stars, galaxies, and Solar System objects in its first year of operations than all previous telescopes combined. 
 
The rich datasets generated by astronomical surveys are commonly stored as searchable digital databases to be shared with the global scientific community and the general public. Technological and cultural shifts around surveys have transformed the landscape of professional astronomy, and have created new opportunities for education and public outreach. “

About the Speakers:
Keith Bechtol is an Assistant Professor in the Physics Department at the University of Wisconsin-Madison, leading a research group in observational cosmology. He contributes to the design, commissioning, operation, and scientific analysis of several astronomical surveys of the night sky, including the Dark Energy Survey (DES) and the Large Synoptic Survey Telescope (LSST). His scientific interests include dark matter, dark energy, neutrinos, and multi-messenger astronomy.

Ellen Bechtol designs and evaluates informal education experiences in a variety of settings, both in-person and digital. She is currently an Evaluation Specialist for LSST, and is an Education and Outreach Specialist for the Wisconsin IceCube Particle Astrophysics Center. She is especially interested in sharing the excitement of scientific research with new audiences and broadening participation in STEM fields.
 
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Next week (April 24) Bruce Johnson will be back at WN@TL along with his electric car, and along with half a dozen or more of his friends (also with electric cars), all of whom are willing to give you a ride.  All zoom, no vroom.  Bruce will be addressing the question, Can You Live Without A Gasoline Car?
 
Hope to see you soon at Wednesday Nite @ The Lab.
 
Thanks again!
 
 
Tom Zinnen
Biotechnology Center & Division of Extension
UW-Madison