South Pole Telescope

node · earth · Amundsen-Scott South Pole Station, geographic South Pole

A ten-metre millimetre-wave telescope at the Amundsen-Scott South Pole Station, and the station that gives the Event Horizon Telescope its longest baselines - to Chile, to Spain, to Hawaii. Its value to the array is entirely geometric: an interferometer resolves detail in proportion to the separation of its stations, and no station on Earth can be further from Chajnantor in the relevant direction. Its cost is logistical. The site is unreachable for months, and the 2017 observations recorded there could not be flown out until flights resumed at the end of the austral winter, which delayed correlation of the whole campaign. No coordinate is given in this record: the telescope stands within about a kilometre of the geographic South Pole, where longitude is nearly degenerate, and no precise published position could be checked in this session.