Image above: The balloon fully inflated and ready to launch. Image courtesy of CIFAR Senior Fellow Barth Netterfield
On Saturday Jan. 17, six telescopes detached from their balloon and landed back on Earth, bearing 16 days’ worth of rich data about the instants after our Universe was born.
Scientists dispatched SPIDER from Antarctica on New Year’s Day to scan the sky for patterns in the Universe’s oldest light, called the cosmic microwave background. Scientists think that light, composed of thermal radiation left over from the Big Bang, holds the answers to what happened less than a second afterward, leading the universe to expand and become stable enough to harbour galaxies, planets and life.
The extremely cold fluids that kept SPIDER running ran out a few days earlier than the 20-day flight scientists had planned, leading the telescope to land early to avoid the risk of floating too far north. The crew members in Antarctica will have to retrieve the device from its landing location 2,274 kilometres from the station where they are based — about the distance between Montreal and Winnipeg.
Once they retrieve the data, which is still in hard drives on the ice in Antarctica, the research team, including CIFAR senior fellows Barth Netterfield and J. Richard Bond (both University of Toronto), and Mark Halpern (University of British Columbia) of the program in Cosmology & Gravity, will be ready to start analyzing the data. Their best hope?
“Gorgeous, sensitive maps of the sky on large angular scales,” Halpern says.
Pristine images present the best chance that they will be able to spot the patterns they are looking for, the missing proof for the theory of inflation. The theory posits that the Universe expanded exponentially from about the size of a proton to about the size of a grapefruit in a trillionth of a second after the Big Bang and then slowed down very suddenly. That sudden expansion would produce ripples called gravitational waves. “They can’t be made any other way,” Halpern says.
Gravitational waves produce a pattern that is unusual in nature, a pattern which does not look like its mirror image. Trees, rocks and rivers all look normal in a mirror, but objects such as newspapers and button-up shirts do not — the text will be backward and the buttons on the wrong side. Halpern says they’re searching for patterns more like the newspaper example than the tree. “We’re looking for large-scale, mirror asymmetric patterns.”
SPIDER is not alone in this search. BICEP2, on which Halpern and Netterfield are also collaborators, is also looking for evidence of inflation. BICEP2 scientists are also working with another project involving several CIFAR fellows, the European Space Agency’s Planck Telescope. Halpern says SPIDER benefits from a bigger angular scale than BICEP2, which means its scans could cover a bigger swathe of the sky. Its higher sensitivity may also make it easier to determine if dust is interfering with any patterns it detects.