Adam Crain holds a motor from SOAR telescope’s spectrograph control system for which he wrote software.

Carolina professors Wayne Christiansen and Bruce Carney.

Sky's the Limit

SOAR, a new telescope like no other, exists because of work by Carolina scientists and students who collaborated with scientists worldwide.

With a formal dedication on April 17, 2004 SOAR joined the world's exclusive fraternity of cutting-edge research telescopes studying the Southern Skies.

Students and faculty in Carolina's Department of Physics and Astronomy will not only be among the first to use SOAR, but also will carr y on a long tradition of astronomical research at Carolina. In 1824, UNC President Joseph Caldwell brought the university's first telescope from England. Seven years later, Caldwell oversaw construction of the first astronomical observatory at a U.S. university. SOAR will collect 3,400 times more light than that original telescope.

“SOAR will detect objects well over a billion times fainter than the eye can see, and about 20 million times fainter than did that first telescope,” department chair and Samuel Baron Professor Bruce Carney said. “So we can see dimmer objects and stars out to vastly greater distances, and, hence, further back in time.”

SOAR's networked computer system will allow researchers to study the skies above Chile from Chapel Hill. Because the university is guaranteed time on SOAR, researchers will create a list of projects and astronomical conditions ( e.g. dark of the moon) needed to see them. When the right conditions happen, Chapel Hill astronomers will be notified to log onto computers in Chapel Hill to direct the observations and download data in real time.

“We'll get our first cut at science right away and if things aren't going as expected, you can switch filters or make other changes on the fly,” professor Wayne Christiansen said. “Once you've finished, you can get your data over the Internet or by airmail for further analysis. For the most part, we won't need to go to Chile.”

SOAR is not just your average telescope. Recent advances in equipment design and computer technology mean SOAR will allow astronomers to study and learn in ways only dreamed possible a few years ago , Christiansen said.

For starters, SOAR's location is ideal. Based in the foothills of the 20,000-foot Andes mountain range, SOAR sits far away from smog, lights and other visual distractions of city life. The flowing offshore winds and lack of annual rainfall are just right for optimal viewing, Christiansen said. “The seeing is superb,” he said. “In Chile, the center of the Milky Way galaxy passes right over your head. You can observe it for a much longer period of time, and your images aren't distorted as much by atmospheric effects.”

Chile is among the best sites in the Southern Hemisphere for viewing the Milky Way, our home galaxy encompassing Earth and the other planets in our solar system. In addition, the Magellanic Clouds [our closest neighboring galaxies], are in the Chilean skies .

Besides offering an unfettered view of the universe, SOAR is a technological marvel compared with conventional telescopes, Christiansen said. SOAR delivers the highest quality images possible with a large, ground-based telescope.

A major advance will be SOAR's “quick change” instruments. Currently, 4-meter telescopes — such as NOAO's Blanco telescope on the neighboring Chilean mountain, Cerro Tololo — use equipment weighing tons. Depending on what type of equipment an astronomer needs to view the universe, such as infrared or visual cameras or spectrographs, it can take a day or more to change settings and tools.

That scenario won't happen with SOAR. Thanks to improved design, lightweight equipment and computerized remote controls, SOAR can “quick change,” allowing researchers to respond immediately to astronomical phenomena when they happen.

“With SOAR, the minute something like a supernova comes up, we'll be all over it,” Christiansen said. “We'll be able to react to unexpected events when they happen.”

Adam Crain, a 2003 Carolina graduate from Hickory, N.C., developed software to drive SOAR's remote astronomy. “I spent three months in La Serena, Chile working with the SOAR team. I wrote software, participated in design meetings and learned about software control of instrumentation in general.”

Crain's first software piece was for the Goodman Spectrograph control system, an imaging spectrograph built at UNC.  “The control system coordinates the motions of eleven motors and two actuators,” Crain said. “The system's distinguishing features include its multithreaded architecture, remote capability, automated configuration changes and observing deck control via a PDA.  Astronomers around the world will use the system to perform measurements without traveling to Chile.”

To handle large data files containing images and spectral datasets from SOAR instruments, Crain created a remote observing tool. The tool consists of two pieces of software, a server and a client that facilitate the data transfer. Astronomers can compress data and view glossy representations within seconds of acquisition.  The full datasets transfer in parallel, arriving minutes later.  The toll automatically displays the images and overlays celestial coordinates on the images, allowing astronomers to make intelligent adjustments to the telescope position.

Prior to SOAR, department faculty and students have primarily used national facilities for observations. These include the National Optical Astronomy Observatory, the National Radio Astronomy Observatory, the Hubble Space Telescope, the Chandra X-ray Observatory, and other facilities including the Australia Telescope, the Anglo-Australia Telescope, and the Keck Observatory. Teaching and research facilities include a 24-inch remote-controlled telescope at the Morehead Observatory on campus, and two small robotic telescopes out in the mountains at the Pisgah Astronomical Research Institute .

For more information:

SOAR site webcam
http://www.physics.unc.edu/research/astro/soar_cams.php

SOAR telescope website
http://www.soartelescope.org/

SOAR interior webcam
http://www.ctio.noao.edu/soar/netcam.html