By Erin Hallissy
Students Enjoy Rare Opportunity to Research the Galaxies
Courtesy of the NAIC - Arecibo Observatory, a facility of the NSF
Undergraduates rarely have the opportunity to use the world's largest and most powerful telescope in Puerto Rico, but Saint Mary's is now among an elite number of colleges nationwide that have sent students to help research cosmic phenomena that was unheard of until the last two decades — galactic winds in the Milky Way and other parts of the universe.
In January Term 2010, senior Jillian Eymann and junior Seth Felix became the first two Saint Mary's students to go to the Arecibo Observatory — one of the most important national centers in the world for radio astronomy research. They were among some 30 undergraduates at 16 universities throughout the United States who participated in a research consortium funded by the National Science Foundation.
Their journey, and the research they and other SMC students will continue for years, was made possible through the professional connections of astrophysics professor Ron Olowin. Two years ago at an international cosmology conference in Venice, Olowin was invited by astronomers Riccardo Giovanelli and Martha Haynes of Cornell University to join the Arecibo Legacy Fast ALFA Survey. (ALFA is an acronym that refers to the wavelength range at which the instrument works.) The project is known by the nickname ALFALFA.
"Saint Mary's students had never had the chance to work with national and international researchers on this kind of project," says Olowin, who is on sabbatical this year but could not pass up the chance to travel to Arecibo for the research with his students. "It's almost a stratospherically rare opportunity."
Jillian Eymann, Victoria Mendoza and Peyton Murray.
Mapping the Sky
Located in a large limestone sinkhole that cradles its weight, the massive radio telescope receiver — the size of 26 football fields — is the largest in the world. It is also a striking sight, with a huge 1,000-ton antenna with a triangular symmetry. In operation 24 hours a day, the telescope is available to scientists from throughout the world, including students working on master and doctoral dissertations.
The ALFALFA consortium is mapping a large area of the sky to detect neutral hydrogen gas (HI) in other galaxies. It is expected to detect more than 30,000 galaxies out to a distance of 750 million light years.
Olowin points out that it wasn't until 1923 that Edwin Hubble was able to verify the existence of other galaxies, and that the Milky Way was not the whole universe but only one of the trillion galaxies in it. Amazing technological progress in telescopes in the 20th century has allowed astronomers to confirm the existence of a wide range of extraterrestrial wonders, including pulsars, evidence of black holes and ripples from the Big Bang.
The ALFALFA consortium is looking at only recently discovered evidence of big flows of winds in our galaxy, the Milky Way. Using the Arecibo radio telescope, researchers — including the undergraduate students — can detect the flows of what Olowin calls "moving clouds of interstellar hydrogen."
"You see storms of moving gasses," Olowin says.
The receiver at the Arecibo Observatory.
Observing the Past
The ALFALFA researchers, including Eymann and Felix, had a window of telescope time in the wee hours of several January mornings to observe the high-velocity gas clouds and even the rotation of distant galaxies, millions of light-years away. They also labored in a computational lab where they synthesized and analyzed the data they had gathered.
"The time we had there was pretty intense," says the 21-year-old Eymann. "We didn't sleep a lot."
The data in the telescope readouts "are not spectacular or sexy" looking, says Felix, 21, a physics major and math and computer science minor. However, they point to wondrous secrets that are deepening human understanding of the universe.
Eymann and Felix say the galactic winds they were able to detect are almost like a "star nursery" of hydrogen winds that are the precursors to the formation of stars.
"It's a way of looking into the past," says Eymann, who is majoring in physics with a minor in astronomy. "We saw enough to know it's beautiful."
Eymann was particularly impressed by the scale of the instruments they were working on.
"It's the size of the pyramids," she says. "Working on an instrument that is so huge was utterly impressive."
Felix, who describes himself as "really into particle physics," enjoys computer programming and mathematics, and he spent a lot of time learning the program language used to analyze the ALFALFA data. He says that he was more familiar with the program than other researchers they worked with in January, so he was able to help others.
Felix and Eymann relished the chance of meeting other undergraduate and graduate students, along with professors from throughout the country who may be able to assist them with future graduate studies of their own.
Olowin says that kind of experience is invaluable, and that other Saint Mary's students will be able to travel to Puerto Rico in future Jan Terms and directed courses to do research at the Arecibo Observatory.
"Saint Mary's has never had such a rare opportunity, especially involving undergraduates at world-class research centers," he adds.
Although he is on sabbatical, Olowin was granted permission by the College to engage the students in a directed-studies course for the ALFALFA project during the spring term. This offered another opportunity for travel to Arecibo and other workshops, including one at Humboldt State University with another member of the ALFALFA team, astronomy professor David Kornreich.
Along with Eymann and Felix, senior Victoria Mendoza, 21, junior Peyton Murray, 20, and junior Kurt Thompson, 20, are in the course. Eymann, Mendoza and Murray went to Puerto Rico in late February for a week of training, observations and data reduction related to the ALFALFA research.
The data reduction included removing extraneous material, including the radar transmissions from the San Juan airport and global positioning satellites.
During the course of the analysis, Mendoza discovered in the data sets evidence of a previously undetected galaxy.
"I was looking at the data and I said, ‘This blob right here, that's so funny, that ought to be something.' (Olowin) said ‘that is something. It may be a galaxy'," Mendoza says. "I was so excited. I felt a rush that day and the next day, and I was trying to find as many as I could. I saw 20 other possible detections."
Olowin is just as excited as Mendoza by the ALFALFA research findings.
"Not only are we discovering a new class of galaxies — perhaps dwarf galaxies — we're actually discovering ones that haven't been identified before in the catalogues," Olowin says. "The scans enable us to actually measure their distance and rotation millions of light years away."
For a week, the students and Olowin worked night and day on the ALFALFA data and with other researchers on pulsar and radar observations of the ionosphere, using the most powerful radar in the world. The radar can measure asteroids and determine their composition.
Olowin says the students "were incredibly enthusiastic and hard-working. They hardly wanted to break for lunch or supper."
Saint Mary's ALFALFA grant has about three years to go, so more undergraduates will be engaged in research and courses, including future Jan Term classes.
"That's a real privilege. We don't get these opportunities very often," Olowin says. "We're sending our students to a world-class observatory and being exposed to ‘big science.' "