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Photo by Gregg Trusty/LSUS News

Bird’s-Eye View of the Universe

After finishing the installation of a new radio telescope on the roof of Bronson Hall, (from left) Cat Cole, senior math major; Dr. Laura Whitlock, assistant professor of physics; Cheri Veillon sophomore physics major, and Steven Smith, a senior physics major, pause in front of their handiwork. The 7-foot diameter “Small Radio Telescope” was purchased with a Louisiana Board of Regents Support Fund Grant and will have a new laboratory-based course developed around it. Whitlock has formed a collaboration with scientists and engineers at the MIT Haystack Observatory in Westford, Mass., that will help facilitate the new radio astronomy resource at LSUS.

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Listen Up! A New View of the Universe Comes to LSUS

A Louisiana Board of Regents grant allowed the creation of a radio astronomy resource at LSUS in the form of a 7-foot diameter radio telescope (called the SRT for “Small Radio Telescope”) with a new laboratory-based course developed around it.

Dr. Laura Whitlock, assistant professor of physics, headed this effort in collaboration with scientists and engineers at the MIT Haystack Observatory in Westford, Mass. In fact, this project would not be possible were it not for a newly formed collaboration between MIT and LSUS. Whitlock attended the National Science Foundation’s Chautauqua short course on Radio Astronomy in the Undergraduate Classroom held at Haystack in May 2004. This led to the firm commitment on what an important new resource radio astronomy could be for LSUS and to the collaboration with MIT scientist Dr. Preethi Pratap and her staff at Haystack which could make it possible.

Human beings have looked at the night sky since the very beginning of their time on Earth,” Whitlock commented. “Until the 20 th Century, however, the view was limited to the very narrow range of wavelengths that human eyes were capable of detecting.”

Only the radio and optical regions easily transmit through the atmosphere to be detected on the ground. “The study of radio waves emitted by objects in the universe is known as radio astronomy,” the former NASA astrophysicist said, “and it is rather ‘sexy’ as science goes. It looks at interesting objects and processes in the universe such as the gases between stars, supernova remnants, and pulsars.”

The study of radio astronomy can result in an excited, engaged student, and that is the ultimate goal of Whitlock’s efforts. The availability of a course in a new, exciting field of astronomy is intended to strengthen the science interests of LSUS students.

What is a Radio Telescope?

In some cases, it looks exactly like a large satellite TV dishes people used to have in their backyards. There are three basic elements to a prime focus, radio telescope: the reflector, the feed and transmission line, and the receiver. The reflector collects power from astronomical sources. The feed and the receiver system are located at the prime focus. The receiver amplifies the radio signal. The amplified radio signal is then processed by a computer. The receiver is configured in such a way that throughout the amplification process, the signal remains directly proportional to the strength of the incoming radiation. So the resulting image or spectrum is a true representation of the emission from the astronomical source.

The SRT is capable of continuum and spectral line observations at 1.42 GHz, the frequency naturally emitted by neutral hydrogen. (Keep in mind that over 90% of the matter in the Universe is hydrogen.) There are four to five sources which are routinely observable by the SRT. These include localized sources such as our Sun, Cassiopeia A, Cygnus X, and non-localized sources such as the Galactic hydrogen line emission which will allow students to determine the rotation curve of the Milky Way Galaxy. Radio telescopes are, in fact, an excellent teaching tool for physics, astronomy, microwave engineering, and digital computing. Its use involves astronomy, digital signal processing, software development, and analysis.

A New Course at LSUS

Introduction to Radio Astronomy was taught at LSUS for the first time in Spring 2006 as a special topics course, Physics 487. The aim of the new course will be to provide an introduction to the basics of radio astronomy and an introduction to the techniques that allow radio astronomers to obtain and analyze data from radio telescopes. Students entering the course will, in general, have first-hand experience only with optical astronomy. It will be an important component of the radio astronomy course to provide them with a pathway for understanding the three main differences between the two approaches to the universe: (1) the different sources that are seen in the Universe; (2) design of the radio instruments; and (3) the resulting radio data that are gathered and need to be analyzed. As an illustrative example, we can examine the fact that both optical and radio astronomy use telescopes to detect the emissions of those types emitted by objects and process in space. However, there is a big difference in design between an optical telescope detector and a radio telescope detector. Optical astronomy is the study of the visible part of the electromagnetic spectrum, with wavelengths of approximately 400 nm (purple) to 700 nm (red). Radio wavelengths are much longer; the radio spectrum ranges from approximately one millimeter to hundreds of meters.

Six students and one professor (Dr. Richard Thompson, LSUS Chemistry professor) signed up for the course. It was hoped that part of the course would be to construct the telescope, however a delivery delay did not allow this to occur. To compensate for this, Dr. Whitlock arranged with the MIT Haystack Observatory to operate their SRT remotely. This allowed for the students to see the capabilities of the telescope, and for the Haystack staff to learn about the difficulties in remote operation in order to inform future software modifications. The telescope parts finally arrived in early June 2006. The Physics 487 students returned after the semester ended to help assemble the telescope.

By completing the observations required as a part of the Introduction to Radio Astronomy course, students will become qualified to request time on the Haystack 37-m radio telescope and pursue publishable research projects. Such an opportunity has never been available before at LSUS. It is believed that this will prove highly attractive to a pool of area students who would not have previously considered LSUS.

The inaugural regular offering of Introduction to Radio Astronomy will be in the Spring 2007 semester.