A team of University physicists and engineers met with collaborators in Palestine, Texas this summer to assemble and test a telescope complex, known as SPIDER, that when launched will help scientists understand the fundamental physics of a period during the early universe.
Currently, most of SPIDER has been disassembled and is on its way by boat to Antarctica. When it arrives in late October, the team will reconstruct the instrument and launch it in late December, during the Austral summer.The device is the result of research that began in 2000 by Princeton, the University of Toronto and Caltech. It was built at NASA’s Columbia Scientific Balloon Facility.
When the instrument is in the air, it points away from the sun, Jon Gudmundsson, a graduate student in the physics department who worked on SPIDER last summer, explained. The wind at the South Pole flows in a “circumpolar” fashion, meaning that it will keep the balloon circling around the South Pole every 10 days. While in the air, SPIDER will collect measurements of polarized light at particular frequencies generated by inflation, a period when the universe expanded rapidly for a very short period of time. SPIDER measures the energy of gravitational waves that existed in the early universe by looking at polarized light that has been traveling since that time.
After 20 days of being 120,000 feet in the air, with 99 percent of the Earth’s atmosphere below it, SPIDER will have collected all the data it needs. It will then descend by parachute, Gudmundsson said.
Once SPIDER has crashed to the ice, several scientists and riggers will fly to the site of the crash and recover the hard drive and as much equipment as possible. This mission is dangerous in Antarctica,Gudmundsson explained, because the frigid temperatures limit the amount of time the recovery team’s plane can operate outside. Consequently, some materials may be left behind and picked up at a later time.
But in the Texas heat, the team spent months this summer troubleshooting errors within and between the subsystems of SPIDER in order to prepare the device for launch. The scientists encountered new problems in every subsystem, and more remain to be fixed before the device is officially launched, according to Anne Gambrel, a third-year physics graduate student, who has been working on the project with Gudmundsson.
“The main thing we did was essentially crisis management,” Gambrel said. She noted that in Antarctica, the trick will be to know when to stop testing and when to decide to launch.
Once SPIDER is in the air, there will be no way to fix anything that goes wrong, she explained. Balloon-borne experiments have historically been prone to failure. While the team has used past disasters to ensure success, both Gudmundsson and Gambrel said jokingly that there’s no way to know what could go wrong.
Both Gudmundsson and Gambrel said that what they are looking forward to most is the moment of the launch.
“I don’t know what that feeling is going to be,” Gudmundsson, who has been working on the project for five years, said. “But when that thing goes in the air … It’s going to be great.”
Gambrel said she was enthusiastic about the prospect of the launch and will be working on a successor to the SPIDER device, known as SPIDER II.
“It’s going to be so cool,” she said of the launch.