Antarctic boffins hope stratospheric gravity wave hunter returns to Earth
Telescope circles globe propelled by polar winds
Boffins in Antarctica are nervously watching the skies for the planned descent of an instrument package hoisted into the stratosphere on January 1 with the aim of seeking out gravity waves.
The experiment, called SPIDER, combines a polarimeter designed to look for signals that would either validate or exclude “GUT-scale” (grand unification theory) inflationary models.
Two secondary experiments will look at the interstellar medium in the Milky Way; and measure the weak gravitational lensing of the cosmic background radiation (CMB) polarisation.
The craft's six 30cm-apeture telescope inserts are helium-cooled to 1.5˚K.
The instruments on board SPIDER include six cameras, and the whole package is travelling around Earth at roughly 36,500 metres (120,000 feet), propelled by circumpolar winds.
The video below shows the launch near McMurdo Station.
On January 3, Princeton research scholar Zigmund Kermish wrote that SPIDER had reached its “float” altitude successfully, that flight systems like attitude control were operating, and that the team was ready to begin working with the craft's instruments.
However, it's after the balloon returns to ground level that the researchers will have perhaps their most difficult challenge: with no way to precisely control the craft's descent, the researchers will only have a week to locate SPIDER and retrieve its data.
Collaborators in the project include Princeton University, with funding from NASA, the NSF and the David and Lucille Packard Foundation, the Columbia Scientific Balloon Facility, the Natural Sciences and Engineering Research Council of Canada and the Canadian Space Agency. ®