The South Pole is perhaps the most isolated spot on the face of the Earth.  After Roald Amundsen reached it in 1911, it was not until March of the following year that the world learned of his great feat.  Such was the nature of communications in the heroic age of polar exploration.  In the 21st century information travels from the South Pole much more quickly, as evidenced by the fact you are now reading these words. 

Although communications have certainly improved, here at the South Pole we are still far removed from the “wired world” most experience in their daily lives.  Because of its furthest south geography, the Earth’s curvature blocks the vast majority of satellites from being visible above the horizon at the South Pole.  Since communication satellites are launched into high orbits where they remain stationary relative to a spot on the Earth, otherwise known as a geosynchronous orbit, only those few in what are called “high inclination” orbits become visible to the satellite antennas at Amundsen-Scott Station.  Geosynchronous satellites don’t really remain stationary over a spot on the globe, but instead travel in a small figure-of-eight pattern when viewed from the Earth.  So when the communication satellites are in the most southern portion of the figure-of-eight, from our perspective they pop up above the horizon and connect us to the rest of the world. 

Geosynchronous Satellites Are Visible From The South Pole When Below The Yellow Line

 

We currently use two different types of satellites for our broadband communications.  The GOES or Geostationary Operational Environmental Satellite 3 is an old weather satellite that was launched in 1978.  Although it lost its imaging ability long ago, the communication transponder still works and allows us to make phone calls and access the internet at about the speed of a dial-up modem for the 6 or 7 hours a day it is above the horizon.  Run by the University of Miami for the National Science Foundation, it has a ground station located in Florida.  When Hurricane Isaac rolled through the Caribbean recently, we lost our GOES connection for a couple of days. 

The other system we use belongs to the National Aeronautics and Space Administration (NASA) and is shared with the International Space Station and the Hubble Space Telescope.  The ground station is located at White Sands, New Mexico.  The Tracking and Data Relay Satellite System (TDRSS) provides two channels; a fast channel for transmitting science data off the ice and a much slower channel for telephone and internet services.  It is fast enough, however, to allow video teleconferencing for medical, science, and administrative activities.  Since this is a shared resource, we typically only have access for a few hours per day. 

The GOES (near) & TDRSS (far) Antenna Domes – September 2012 – Photo by Dale Mole’

When these main communication satellites are below the horizon or otherwise unavailable, we do have access to the Iridium satellite system, allowing us to make phone calls.  In order to provide world-wide coverage, the more than sixty Iridium satellites were launched into polar orbits, so they travel around the world going north and south, rather than the usual east and west direction.  Orbiting about 500 miles (800 kilometers) above the Earth, under the right conditions each satellite can handle more than 1000 phone calls simultaneously.  The Iridium satellites also provide a great show in the polar night sky.  Their highly reflective antennas are roughly the size of a residential door and are made of polished aluminum coated with silver and Teflon, giving them a mirror-like surface.  These antennas reflect the Sun’s rays and produce what resembles a slow moving “shooting star” that gradually builds in intensity then fades over the course of a few seconds. 

A Diagram Of How Iridium Flares Are Produced