High school students discover millisecond pulsar, help search for gravitational waves
High School students have discovered a new star that spins as fast as a Formula 1 race car’s engine. This discovery may someday help astronomers detect ripples in spacetime known as gravitational waves.
The special star, called a millisecond pulsar, was discovered independently by Jessica Pal of Rowan County High School (KY) and Emily Phan of George C. Marshall High School (VA) on January 17, 2012, and was confirmed by Max Sterling of Langley High School (VA), Sydney Dydiw of Trinity High School (VA), and Anne Agee of Roanoke Valley Governor’s School (VA). These students are part of the Pulsar Search Collaboratory (PSC) project, run by the National Radio Astronomy Observatory (NRAO) in Green Bank, WV, and West Virginia University (WVU). As part of the PSC, the students analyze real data from NRAO’s Robert C. Byrd Green Bank Telescope (GBT) to find pulsars.
Once the pulsar candidate was reported to NRAO, a followup observing session was scheduled on the GBT. On January 24, 2012, observations confirmed that the pulsar was real.
Pulsars are spinning neutron stars that sling “lighthouse beams” of radio waves around as they spin. A neutron star is what is left after a massive star explodes at the end of its “normal” life. With no nuclear fuel left to produce energy to offset the stellar remnant’s weight, its material is compressed to extreme densities. The pressure squeezes together most of its protons and electrons to form neutrons; hence, the name “neutron star.” One tablespoon of material from a pulsar would weigh 10 million tons.
The object that the students discovered is in a special class of pulsar that spins very fast – in this case, about 324 times per second. Millisecond pulsars, the fastest-spinning pulsars, are highly stable and keep time more accurately than atomic clocks. Not much is known about them, however.
As Dr. Duncan Lorimer, an astronomer at WVU states, “Despite having known about millisecond pulsars for almost thirty years, they are so difficult to find that our knowledge of these objects is still in its infancy.”
One thing we do know, however, is that because of their stability, these pulsars may someday allow astronomers to detect gravitational waves.
Dr. Maura McLaughlin, another WVU astronomer explains, “Gravitational waves are ripples in the fabric of spacetime predicted by Einstein’s theory of General Relativity. We have very good proof for their existence but, despite Einstein’s prediction back in the early 1900s, they have never been detected.”
Millisecond pulsars, however, could hold the key to that discovery. Like buoys bobbing on the ocean, pulsars can be perturbed by gravitational waves.
“Gravitational waves are invisible,” says McLaughlin. “But by timing pulsars distributed across the sky, we may be able to detect very small changes in pulse arrival times due to the influence of these waves.”
Millisecond pulsars are generally older pulsars that have been “spun up” by stealing mass from companion stars, but much is left to discover about their formation.
Dr. Duncan Lorimer says, “This latest discovery will help us understand the genesis of millisecond pulsars. It’s a very exciting time to be finding pulsars!”
The PSC is a joint project of the National Radio Astronomy Observatory and West Virginia University, funded by a grant from the National Science Foundation. The PSC includes training for teachers and student leaders, and provides parcels of data from the GBT to student teams. The project involves teachers and students in helping astronomers analyze data from the GBT, a giant, 17-million-pound telescope.
Approximately 300 hours of the observing data were reserved for analysis by student teams. These students have been working with about 500 other students across the country. The responsibility for the work, and for the discoveries, is theirs. They are trained by astronomers and by their teachers to distinguish between pulsars and noise.
In addition to this discovery, five other astronomical objects, including four pulsars, have been discovered by students. This is the first millisecond pulsar.
Those involved in the PSC hope that being a part of astronomy will give students a greater awareness of and appreciation for scientific research. Maybe the project will even produce some of the next generation of astronomers.
The PSC will continue through the 2012-2013 school year. Teachers interested in participating in the program can learn more at this link http://www.gb.nrao.edu/epo/psc.shtml. The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.
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QUOTES FROM STUDENTS
Sydney Dydiw: “PSC makes me want to discover the entire universe and find every pulsar out there. I may not major in astronomy at college, but I definitely want to learn more about it.”
Emily Phan: “I feel very fortunate and have a sense of accomplishment that I was able to contribute to the PSC organization and the science community.”
Anne Agee: “I am considering pursuing astronomy as a career choice. The Pulsar Search Collaboratory has opened my eyes to how fun astronomy can be!”
Jessica Pal: “When you discover a pulsar, you feel like you’re walking on air! It is the best experience you can ever have. You feel awesome and you become ‘famous.’ You get to meet astronomers and talk to them about your experience. I still can’t believe I found a pulsar. It is wonderful to know that there is something out there in space that you discovered.”
