Astronomy On Ice

Shortly after attainment of the South Pole…first by Roald Amundsen in December of 1911, then by Captain Robert Scott in January of 1912…Rear Admiral Robert Peary inquired of Professor Edwin Frost at the University of Chicago as to the suitability of the South Pole for astronomical observation, given its high-altitude, low humidity, and long winter night.  Although he received a positive response, it would be more than 50 years before astronomy became the main focus of scientific endeavor at this remote outpost.  It would take the pioneering efforts and determination of an American physicist, Martin Pomerantz, to make this daydream a reality.   

Dr. Pomerantz began his career in science by studying the then relatively new field of cosmic radiation and he led a number of expeditions to measure cosmic rays at varying latitudes, and therefore varying magnetic fields, around the world.  His first experiments at the South Pole started in 1964.  He saw the potential for the South Pole as an observation platform since its proximity to the South magnetic pole meant that charged cosmic rays could be detected without deflection by the Earth’s magnetic field, in contrast to studies at lower latitudes.  Much like Peary decades before him, he also appreciated the fact that astronomical observations could be performed over a long period of time; the extreme cold temperatures meant that relatively little water vapor remained in the air (an important advantage for infrared astronomy); and that the elevation of the polar plateau was similar to other high-altitude observatories around the world.  

The Earth’s Magnetic Field Deflects The Path Of Many Cosmic Rays, Except At The Poles

Dr. Pomerantz’s work led to the insight that the Sun, like the Earth, has a magnetic field.  While it was originally thought the Sun’s magnetic field was much stronger, it turns out that it is similar in strength to that of the Earth.  He also pioneered the field of helioseismology (Sun-quakes), the study of pressure waves from the Sun.  You can think of the Sun as an enormous bell ringing at very low frequencies giving off vibrations or pulsations.  These pulsations provide important clues as to the Sun’s internal structure.  

Pressure Waves From The Sun Can Be Measured On Earth

 

In 1979, Dr. Pomerantz and colleagues conducted the first Antarctic observations with a small telescope mated to sodium vapor resonance cell, a special sensor designed to look at the Sun.  Although these observations were not officially authorized, Dr. Pomerantz later said, “We had to find a way to convince people that the South Pole was the place for astronomy. Sometimes you need to circumvent the rules. Our bootleg experiment enabled us to obtain the clearest pictures of the sun that had ever been obtained from any place on earth. It proved once and for all this was a superb place for astronomy.”   Able to record the Sun’s vibrations without interruption for more than 100 hours, they greatly enhanced our knowledge of the Sun.

Martin A Pomerantz Observatory In The Frozen Mist – March 2012 – Photo by Dale Mole’

Dr. Pomerantz was recognized for his efforts in polar astronomy with the dedication of the Martin Arthur Pomerantz Observatory (MAPO, pronounced May-poe) in 1995.  With exterior construction taking place in the 1993-1994 austral summer and interior work completed during the 1994 winter, the two-story elevated structure has 270 square meters of interior space.  It is located about one kilometer from the main Elevated Station in what is known as the “dark sector”, an area where extraneous electromagnetic radiation (including light and radio waves) is minimized.  MAPO has pioneered and proven many of the technologies used by the other laboratories in the dark sector through projects such as the Antarctic Muon And Neutrino Detector Array (AMANDA), the South Pole Infrared Explorer (SPIREX), the Cosmic Background Radiation Anisotropy experiment (COBRA), and the Advanced Telescope Project (ATP).

Martin A Pomerantz Observatory – October 2012 – Photo by Dale Mole’

A colleague observed, “In my view, Martin’s greatest talent was to have the vision to see how a new and important experiment could be done and then to gather the very best people to do the experiment.  He made a study of just how Antarctica could be used and then convinced others of its value.  He was almost single-handedly responsible for the development of South Pole into a major site for astronomy.  Dr. Pomerantz demonstrated remarkable foresight by establishing research facilities or laboratories in Antarctica, where observations of the Sun are unimpeded by clouds or the setting sun, and the atmosphere features a window in the Earth’s magnetic shield.  He also showed tremendous courage, working in Antarctica when it was still a very hazardous proposition.”

Amundsen – Scott South Pole Station – 2 OCT 2012 – Photo by Dale Mole’
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2 thoughts on “Astronomy On Ice

  1. What a remarkable scientist Dr Pomerantz must have been. Thank you for outlining something of his vision and contribution to astronomy. It amazes me the incredible astronomy that is being done in Antarctica, and the incredible engineering feat of the Ice Cube Neutrino experiment, but it is getting nothing like the public recognition of other “big ticket” science experiments. I suppose National Geographic or BBC Horizon filmmakers prefer to make their astronomy documentaries in more pleasant environments, like California and Hawaii. My own knowledge of what is going on in Antarctica was sparked by an excellent book I recently finished reading, The Edge of Physics by Anil Ananthaswamy. What a pity it could not have been made into a TV series, since it explains a huge amount of modern physics and astronomy in very accessible language. I wish all you scientists currently working in Antarctica the very best, and want you to know that your work is appreciated! I’m sure some of the research from South Pole astronomy will one day be recognized in the form of a Nobel Prize for Physics. But even if not, know that to appreciative amateurs and science enthusiasts, you guys are like the astronauts who went to the moon – true cultural heroes of a scientific civilization!
    Peter

  2. Peter,

    Thanks again for your kind words…and the book recommendation “The Edge of Physics.” I will have to get a copy when I return to the United States.

    Regards,
    Dale (from Amundsen-Scott South Pole Station)

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