The BLAsT Class poses at the Dish with Fantastic Aussie Tours bus driver, Jon. // Photo by Samuel I. Beard, Jr.
On the 27th of July, we got the privilege to visit the Parkes Dish, a large single-dish, 64-meter radio telescope, and we were given a personal tour by Operations Scientist John Sarkissian. A radio telescope works in the radio wavelength of the electromagnetic spectrum, picking up radio waves from distant space bodies. Unlike an optical telescope, a radio telescope does not receive visuals. Instead, the waves it receives are translated into intensity maps for analysis. Radio astronomy is a subfield of astronomy and was first introduced by Karl Janksy to gain a deeper understanding of our universe. Radio telescopes have to be large because radio waves are large, so they need something even larger to collect and focus the light.
While giving us a tour of the Dish, Sarkissian talked with us about the 2000 movie The Dish, which we had actually watched the day before on the 5-hour bus ride from Katoomba to Parkes. He showed us the locations where the movie was filmed and helped separate fact from fiction. Although much of the drama was based on actual events at various stations over several Apollo missions, the actual tracking of Apollo 11 went much more smoothly than the movie suggests. The only snag was the wind, which hit up to 110 km/hr just as the Dish needed to be tilted essentially on its side to point at the Moon.
John Sarkissian explains the Dish's counterweights and gearing system to us. // Photo by Tyler Coleman
During its nearly sixty years of operation, the large and isolated Dish in a kangaroo-and-sheep-inhabited field in Parkes has aided in many important astronomical studies. While best known for its broadcast of the Apollo 11 moonwalk, the Dish is responsible for our re-thinking the size of the known universe. The discovery of pulsars fifty years ago by Jocelyn Bell set the stage for the Parkes Dish to discover nearly two-thirds of all known pulsars, effectively expanding our known universe by ten times. A pulsar is a minuscule but highly magnetized remnant of a star emitting strong electromagnetic radiation. The pulses they emit are unimaginably regular, and can be reliably picked up by our radio telescopes.
The Dish recently attracted the attention of Mark Zuckerberg and Russian billionaire Yuri Milner, whose “Breakthrough Initiatives” project buys a quarter of the Dish’s observing time to look for signs of extraterrestrial life. As Sarkissian told us, even if nothing is found in the way of extraterrestrial life the information gathered in this endeavor will help advance the science of radio astronomy and our general knowledge of the universe. So what happens if they do find evidence of intelligent extraterrestrials? Sarkissian said that the official protocol is to “tell everybody” because, let’s face it… “if the CIA can’t keep a secret, how can we?”
The Dish is only passively searching for extraterrestrial signs, however, and is actively used by astronomers throughout the world for whatever they need. Going by the “open skies” motto that the Commonwealth Scientific and Industrial Research Organisation (CSIRO) works by, any astronomer with a good reason to use the telescope is allowed access to it, either on-location or via the Internet (after having been trained, which is also provided if their request is accepted).
In all, it was a great honor to get to tour the Dish in a way most people do not get and talk to one of the most knowledgeable people in the field.
ABOUT THE AUTHORS:
BLAsT Class student Cristal Hernandez holds up the 1000-ton Dish with apparent ease.
Hello! My name is Gaby Loredo, I am a sophomore majoring in Victims Studies. I decided to take this class after Dr. Miller convinced me to sign up when I was registering for my fall classes. This is my first study abroad trip and so far I am loving it. So far I am enjoying this trip and can't wait to keep exploring!
My name is Diane Brewer, and I am a junior at Sam Houston State University majoring in Psychology. I took this class because I have loved astronomy since I was a child. I took Solar System Astronomy my second semester in college, and I was going to take Stars & Galaxies this past semester but couldn't pass up the opportunity to study abroad and get credit for it instead. When else would I get the chance to see Australia and a total solar eclipse AND get credit for college? Never. So I had to come. I never thought I would get to see the Southern Cross, and on our first night here I got to see it. I'm excited to learn everything else about the southern hemisphere's night sky.