Affectionately known for years as “the observatory” or the “Green Bank Observatory,” the facility more formally known at the National Radio Astronomy Observatory officially became the Green Bank Observatory – on paper October 1, to the public October 8.
A hub of science and education in the mountains of West Virginia, the observatory opened in the 1950s when it was determined that the United States needed to enter the race to discover what exists beyond Earth and its moon – as well as what might exist beyond the Milky Way.
Saturday, GBO director Karen O’Neil ushered the facility into a new era with its new name – citing the efforts of those who made the observatory what it is today.
“The trailblazers of American radio astronomy declared this facility their home, established the first-ever National Radio Astronomy Observatory within the United States and what was actually the first ever National Science Lab that was built for open access so that anybody around the world could apply for time and use the time on that facility,” O’Neil said. “Today the legacy of those trailblazers remains alive and well.”
The goal of the observatory is to explore the unknown and educate future scientists who want to answer the bigger questions about the universe.
“We’re here to discover,” O’Neil said. “We’re here to discover black holes, stellar birth, pulsars, Big Bang energy, universal expansion and the very origins of life. We’re also here to foster innovation and curiosity, to escape from the noise and to learn and to share and to teach. We’re here to educate, to encourage your sense of wonder for the unknown beyond our planet.
“We’re here to invent, to create new technologies in order to see the universe in ways that it has never been seen and has never been possible until now,” she continued. We’re here to see the unseen, to harness the power of radio waves and explore astronomy.”
In the past 60 years, many scientists, from high school students and college students, to visiting astronomers from around the world, have made discoveries using the telescopes at Green Bank.
As the facility prepares for its next 60 years, it’s hard not to say, “the sky’s the limit.”
“I look forward to seeing what the next big discovery coming from Green Bank observatory will be this year, next year and in the years to come,” O’Neil said. “But I also look forward to watching the next generation come to Green Bank and be inspired and engaged in science and engineering and to watch them pass that excitement on to the following generation, and hopefully, to many generations after that.”
One of the first astronomers to work at the NRAO at Green Bank was Dr. Frank Drake – best known for the Drake equation which is used to estimate the number of communicating civilizations in the cosmos or simply put, a way to discover extraterrestrial intelligence.
Drake reminisced about his time at Green Bank and the discoveries – astronomical and other – that he and his fellow astronomers and scientists made at the facility.
“I look back with great pleasure and pride because we did great things in those days,” Drake said. “I wanted to give you a little taste of what life was like back then, as well as point out some things that are obvious once I tell them to you. That is what a role Green Bank Observatory has played, not just in astronomical research in America, but really in effecting the quality of astronomical research in the whole world.”
When the facility was first opened, it was quickly decided it needed telescopes for research. The initial plan was to build a 140-foot radio telescope and a 600-foot radio telescope, which would have been twice the size of the Green Bank Telescope.
“Very early on, we discovered that neither of those was going to happen soon,” Drake said. “There were engineering problems with the 140-foot telescope. The 600-foot telescope was just a pipe dream for the time being. So we very quickly built the 85-foot telescope which is our Tatel telescope. We started using that, and it produced some very good results right away.”
Drake said that at that time, it was easier to get funding from the National Science Foundation. All they needed was a good idea and a proposal.
“Creativity was encouraged,” he said. “We weren’t to just copy the telescopes that had been built around the world. We had to do a better job, do a better telescope and so we had very creative people that came and worked temporarily on the staff.”
One of those people was Grote Reber, the first radio astronomer in the world. Reber built his own radio telescope in the backyard of his home in Wheaton, Illinois. The telescope now resides at the Green Bank Observatory, where Reber personally reconstructed it.
Reber was a creative and innovative character and Drake was excited to work with him.
“When he came here, the first thing he wanted to do was detect radio emission from Mercury,” Drake said. “This is something nobody had the nerve to try because Mercury is always very close to the sun, so it was going to be very hard to observe with a telescope.”
Despite Mercury’s position, Drake granted Reber time on the telescope to observe. The project didn’t go well and ended the way Drake expected.
“I was going to grant anything that Grote Reber suggested,” Drake said. “The next day, he was in my office very angry with me. I had done a really bad job because I’d given him the time he requested. That made me wonder why it was my fault. What was wrong, was the times he had given me for when he wanted to use the telescope was a time when Mercury was below the horizon, so he couldn’t point the telescope there.
“We fixed that and he eventually did try to search for Mercury,” Drake continued. “And what happened? He did what we expected. He detected the sun.”
Reber had an unconventional way of doing research and sometimes went above and beyond for projects, even if they weren’t related to astronomy.
On one occasion, Drake said he and his colleagues were alarmed to see a tractor plowing a field behind the Jansky laboratory. It was unusual to say the least because tractors caused interference to radio telescopes.
A few days later, Reber appeared with a Volkswagen van full of eight oddly dressed characters which piqued Drake’s interest even more.
“We looked at these people and wondered, ‘has he actually found extraterrestrials?’” Drake said. “We went out and asked him. It turned out these people in very strange garments were Catholic nuns. Why did he have eight nuns? He had a project. He was going to solve starvation in the world. He was going to experimentally grow beans in this plot that he plowed up.”
Drake explained that Reber’s plan was to stress the beanstalks by making them climb in a direction, opposite of the norm. A stressed plant is likely to produce more beans to compensate for the stress, he said.
“Grote Reber always did things without asking permission from anybody,” Drake said. “The way to do it – how he was going to stress them – he was going to force the vines to grow counterclockwise around the stakes, and that was the nun’s jobs. The nuns were to take the ties and force the growing beans to grow around the stake in the opposite direction.”
By harvest time, Reber had two plots – a control plot and the stressed plot. After comparing the harvest, he estimated that the stressed plants grew 20 percent more beans.
While the system worked, Drake had a theory as to why it has not been adopted worldwide.
“This has not been adopted throughout the world because it is very labor intensive – you’ve got to find thousands of nuns to use this technique,” he said. “That was the sort of thing that happened in the early days of Green Bank.”
The men found ways to include fun in all their work. When it came time to make proposals to the NSF for new projects, especially building projects for new telescopes, the scientists created a fail-proof equation to estimate the cost of each telescope.
“They discovered there was a simple formula to find the price to build a telescope,” Drake said. “What it produced was actually the weight of steel you needed to make the telescope. It turned out that at that time the cost of steel per pound was the same as the cost of hamburger and so this became the ‘hamburger formula.’”
The “hamburger formula” was used to estimate the cost of the 300-foot telescope and the GBT.
Many of the innovations and discoveries made in Drake’s time have paved the way for current astronomers who are still using equations and studies from the past in their present projects.
“From small acorns, great oaks grow,” Drake said. “Green Bank has played that role, over and over perhaps more than any other observatory in its history. When we look at history, we recognize that the GBT, particularly Green Bank Obser- vatory and all its telescopes has been the primary source of seeds of a lot of very important developments in astronomy.
“The seed was planted here,” he continued. “That is what I wanted to point out. That this place played a fantastic role in all of these projects, you can look at them as family trees. They are all family trees. The GBT starts out as an 85-foot to the 140-foot, which led to the 300-foot, which fell down and that led to the 100-meter telescope. That’s the family tree of the GBT.”
Drake concluded that most telescopes in the world can trace their beginnings back to the Green Bank Observatory. The need for powerful telescopes in other parts of the world was derived from the discoveries made with the telescopes in Green Bank.
The present and the future
Several scientists in the fields of astronomy and astrophysics gave presentations on projects utilizing the GBT, as well as future endeavors in which the GBT will play a pivotal role.
With his presentation “Breakthrough Listen: Our Boldest Effort to Answer Our Oldest Question,” Astrophysicist and Director of the Berkeley SETI Research Center Dr. Andrew Siemion shared the many efforts that have been put into finding extraterrestrial intelligence in the universe.
“The search for extraterrestrial intelligence was one of the first major scientific investigations of the newly christened NRAO at this site in the late fifties, and I think it’s very appropriate for it now to be a big part of the Green Bank Observatory,” Siemion said.
Since the beginning of asking the question “Are we alone?” organizations have yearned to find an answer.
Through the years, as more and more stars and galaxies have been discovered, billions of stars with planets in their orbit have been found. Within those systems, planets which fall in the habitable zone around its host star have been discovered.
Are those planets inhabited or do they have the potential to be inhabited? That is what SETI Institute (Search for Extraterrestrial Intelligence) is trying to answer.
“Just a couple of weeks ago, a pretty large exclamation point was put on this discovery that’s been unfolding over the last couple of decades, and that is that one of the nearest stars to the Earth, just a handful of lightyears away, Proxima Centauri, in fact hosts a planet, Proxima B that exists around the habitable zone of that star. Our nearest stellar neighbor might host a planet that really is not that unlike our own planet Earth.”
Now that planets have been discovered that could be inhabited, the race is on to find out if in fact, there is life on other planets.
In 2015, powerful scientists, including Frank Drake, Yuri Milner and Stephen Hawking, as well as powerful individuals from other industries, have joined together to form the Breakthrough Initiative.
Part of Breakthrough Initiative is Breakthrough Listen, a 10 year, $100 million program.
“There are three telescopes that have been identified that will be part of Breakthrough Listen so far,” Siemion said. “The Automated Planet Finder which is a 2.4 meter optical telescope in California; the Parks Telescope in Australia; and, of course, the Green Bank Telescope, just right outside the building that we’re in today.
“We’ve, in fact, secured twenty percent of the Green Bank Telescope, and we’re using it to conduct the most sensitive, comprehensive and intensive search for extraterrestrial intelligence that we’ve ever done in the past,” Siemion continued. “We’re going to search a million stars, conduct a complete survey of the Milky Way galactic plane and search one hundred nearby galaxies.”
Along with the groundbreaking research, Siemion said Breakthrough Listen will make all its data available for the public to review.
“We’re going to make more scientific data publicly available than any other science project in history and indeed having a public project is a key part of the Breakthrough Listen ethos,” he said. “We want to make everything we do public from our target list to our instrumentation to our software, and indeed, the data that we collect with the Green Bank Telescope and with other telescopes.”
NRAO astronomer Dr. Scott Ransom spoke about his favorite thing – pulsars – in his presentation “Tick-Tock, Tick-Tock! GBO and Cosmic Clocks.”
“I think pulsars are the best thing, and I hope you guys get a flavor of that,” Ransom said. “The GBT has been a crucial and unrivaled success for pulsars for the last years.”
The GBT has been used to discover multiple pulsars through the years, and has even discovered new types of pulsars. Pulsars are spinning neutron stars.
“These are truly exotic objects,” Ransom said. “They’re made almost exclusively of neutrons, and yet they are the size of a city, but yet, the mass of everything that’s in our solar system added together. Mind boggling objects – incredibly strong gravity, strong magnetic fields and they spin like a top. When you move a magnetic field like that, you accelerate particles and out of the ends of those magnetic fields, you get beams of radiation.”
The rotation of pulsars are very precise, more so than even the best atomic clocks.
From the time the GBT was “turned on,” is has been monitoring pulsars and assisting scientists to discover more pulsars.
“Some of the very first science that the GBT did was it pointed at these spectacular clusters of stars known as globular clusters where the stellar densities are so high, stars can interact with one another and they can collide. When they do that, they can manufacture, effectively, new millisecond pulsars,” Ransom said.
The GBT has found almost half of the 140 millisecond pulsars that have been discovered. It has also found magnetars.
“These magnetars are truly unique and this was the first radio magnetar ever found – the GBT played a crucial role,” Ransom said. “To show you how exotic these are, if you take one cubic centimeter [a sugar cube] of the magnetic field from this magnetar, it’s the same amount of power that you would get out of five years from a giant nuclear reactor. That’s just stored in the magnetic field of this pulsar.”
The GBT has also discovered a new type of pulsar known as the transitional pulsars. They are millisecond pulsars that go back and forth between x-ray binaries where the companion star puts gas around the neutron star, causing it to dump out x-rays, and, when the gas stops, it goes back to being a radio millisecond pulsar.
“The last example I want to show you is a spectacular system that was a complete surprise we found in a GBT pulsar survey just a couple years ago,” Ransom said. “A millisecond pulsar is being orbited by two White Dwarf stars in a perfect three body dance. By measuring these gravitational interactions, that big beautiful curve is the distance the pulsar is away from us as it moves through it’s out orbit.”
Ransom is working with NANOGrav – the North American Nanohertz Observatory for Gravitational Waves – in a new project using the GBT and Aerecibo telescope.
“NANOGrav is directly trying to detect gravitational waves that are coming through our galaxy and are going through us and the Earth right now,” he said. “These are coming from super massive black holes at the center of other fighting galaxies through the universe and we think we can measure them with the GBT and Aerecibo.”
In her presentation “Why small objects need big telescopes: A look into the freezer of the solar system,” Dr. Amy Lovell, professor of astronomy at Agnes Scott College, explained why a big telescope is needed to observe tiny objects in the universe.
Using a radio telescope, it is possible to understand the actions of comets and asteroids and to ascertain if they will be a danger to the Earth.
“You have a lot of power from the transmitter and by the time it goes to the asteroid and is bounced off the asteroid and returned, it’s a very weak signal, so having an incredibly large telescope is really important for collecting that really weak signal,” Lovell said.
Since some of these objects are closer to the Earth than others, the GBT is used to collect transmissions from other telescopes in the world. Through the collaboration, the path of asteroids may be understood.
“If you have an asteroid, or object – it could be a comet or anything – moving around in space, as it’s moving around, you can transmit, say, from the Goldstone antenna at the Deep Space Network in California, and those waves bounce off that asteroid and they can return and be collected by the GBT,” Lovell said. “It’s really critical for things like the moon or asteroids that come as close as the moon because it’s not possible to switch your telescope from transmission to receiving within a couple of seconds.”
As studies of these objects continue, Lovell said the GBT could be used to observe a new category of comets.
“There is a lot that can be done with cometary gas spectroscopy,” she said. “Things that can be done for comets, as well as this new category of comets that may have looked like asteroids when they were discovered but behave like comets. It’s a category called active asteroids.”
Also speaking at the event were Associated Universities, Inc. President and CEO Dr. Ethan Schreier, Geoffrey Hemplemann on behalf of Representative Evan Jenkins, Peggy Hawes, representative for Senator Joe Manchin and Senator Shelley Moore Captio via video.
O’Neil presented a trailer for the documentary “Little Green Men,” directed by Sarah Kolberg. The documentary features the pulsar program at GBO which gives high school students the opportunity to use the GBT to search for pulsars.
O’Neil recognized the entrants in the GBO video contest, whose videos were shown during the event.
Honorable mention: Willie O’Ganian “I Love Going to the Open House,” Dodi Shore, “The GBO Blues,” Max O’Ganian, “I Love the GBO,” and the O’Ganian brothers, “Science.” Third place, Cressie Shears, “Green Bank Observatory.” Second place, Ellie White, “What the Green Bank Observatory Means to Me.” First place, Josh White, “What Does the Green Bank Observatory Mean to Me.”
The event, which looked at the past, present and future of radio astronomy at Green Bank, culminated with the unveiling of the new Green Bank Observatory sign and logo.
Suzanne Stewart may be contacted at firstname.lastname@example.org