Polly #2 Wants to Learn About Outer Space~Green Bank, W.V.

Debbie, Candee and I had the opportunity to visit the Green Bank facility of the National Radio Astronomy Observatory in July. The tour is very fascinating, and we had an excellent tour guide who was very knowledgeable. I would highly suggest stopping in for a visit if you’re ever in the area…one of the best parts is that it’s free!

 

The Robert C. Byrd Green Bank Telescope (GBT) is the world’s largest fully steerable radio telescope. It’s called a 100-meter telescope, but it actually measures 100×110 meters. It’s on a wheel and track design and this allows it to view the entire sky about 5 degrees elevation. The structure holds 7300 metric tons (16,000,000 pounds) of moving weight and is so precise that it can be pointed within a few thousandths of an inch.

The design of the GBT is unusual because most telescopes are supported in the middle, but the GBT has an unblocked aperture so that incoming radiation can meet the surface directly. This is useful because it eliminates reflection and diffraction which makes it less responsive.

There are over 2,000 panels on it’s surface which are mounted at their corners on little motor driven pistons which makes it easy to change the surface shape. We were told that each panel is about the size of a queen size mattress and the distance across the surface is equal to 2 football fields!

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The National Radio Astronomy Observatory was founded in 1956 in Green Bank, West Virginia. The headquarters of the NRAO was moved from Green Bank to the campus of the University of Virginia in Charlottesville in the mid 1960’s, and following that, there were several other sites opened throughout the country.

According to the National Radio Astronomy website: Radio astronomy is the study of the invisible universe.

We see the world around us because our eyes detect visible light, a type of electromagnetic radiation. Objects on Earth and in space also emit other types of electromagnetic radiation that cannot be seen by the human eye, such as radio waves. The full range of radiation emitted by an object is called its electromagnetic spectrum.

Radio astronomy is the study of celestial objects that emit radio waves. With radio astronomy, scientists can study astronomical phenomena that are often invisible in other portions of the electromagnetic spectrum.

Using radio astronomy techniques, astronomers can observe the Cosmic Microwave Background Radiation, which is the remnant signal of the birth of our Universe in the Big Bang. They can also probe the “Dark Ages” before the onset of the first stars or galaxies, and study the earliest generation of galaxies. Radio astronomers analyze and explore the black holes that live at the hearts of most galaxies.
Since radio waves penetrate dust, scientists use radio astronomy techniques to study regions that cannot be seen in visible light, such as the dust-shrouded environments where stars and planets are born, and the center of our Galaxy, the Milky Way. Radio waves also allow astronomers to trace the location, density, and motion of the hydrogen gas that constitutes three-fourths of the ordinary matter in the Universe.

Green Bank was chosen for the initial site because of it’s location. It’s very isolated and is in a sheltered valley deep in the heart of West Virginia, in Pocahontas County. This is ideal because the surrounding mountains help to protect the sensitive equipment from man-made radio interference. This is important because the outside interference is harmful to the sensitive radio astronomy observations.

In addition, Green Bank is in the center of a 13,000 square-mile area known as the National Radio Quiet Zone. This was created by Federal regulations to protect the area from harmful radio frequency interference. This means that there is no cell phone coverage anywhere close to the site, which can be a little disconcerting when you’re used to using a cell phone as a way of communicating. When you get close to the actual telescopes, you also can’t use digital cameras to take pictures because of interference from them as well. Because of that, we’d like to give a special thank you to Dave for providing pictures and helping us with this post!

Tags: Polly 2