Just before 4 a.m. on midsummers day, SPIDER, a balloon-borne cosmic microwave background telescope, basked in the sunshine during final pre-flight checks at the NASA Long Duration Balloon facility outside McMurdo Station, Antarctica. SPIDER is an instrument designed to measure faint polarization signals from the primordial Universe and the dusty, polarized components of the Milky Way. I spent my Ph.D. research career developing and characterizing three of the six telescopes nestled inside the cryostat, where they stay at operating temperatures four degrees above absolute zero. The morning of this launch opportunity was the third of three consecutive launch attempts, the first two scrubbed by weather. As SPIDER hung from The Boss, the launch vehicle named for Sir Ernest Shackleton’s nickname from his 1907 Antarctic expedition, Mt. Erebus loomed in the distance. Mt. Erebus is the southernmost active volcano on Earth and was first summitted by Shackleton’s men. It seemed fitting that Mt. Erebus would stand watch over SPIDER before her voyage into the stratosphere, just as it stood sentinel 120 years ago as the explorers trekked into the vast continent. SPIDER took flight a few hours later, lofted by a massive helium-filled balloon, beginning a 16-day journey around the continent.
