Last updated August 29, 2017 at 5:08 pm
As a surf life saver, I usually spend Australia Day on patrol at the beach, but this year was different — very different. This year, I boarded a Qantas Boeing 747 Jumbo Jet, headed for Antarctica.
Australian company Antarctica Flights runs summer sight-seeing trips out of Australian capital cities to tour the Antarctic coast. The Laby Foundation of the University of Melbourne, through its “Classroom Antarctica” program, sponsored Kent Street High School science teacher, Ms Suzy Urbaniak and 18 of her students to take the trip, to educate and excite them about the great, white continent, because last year Suzy received the Prime Minister’s Prize for Excellence in Science Teaching in Secondary Schools.
My fellow ICRAR-UWA PhD candidate, Sarah Bruzzese, and I were invited along to teach the students about cosmic rays and the Earth’s magnetic field.
The atmosphere at Gate 12 was relaxed and festive, and Sarah and I were lucky to get a photograph with the flight crew and penguin. Some passengers got into the spirit of the adventure in their penguin onesies.
As soon as the seatbelt signs were switched off, Sarah and I began setting up our experiments. As well as magnets and compasses and a magnetometer to measure the Earth’s magnetic field, we had Geiger counters and an electroscope to measure cosmic rays. Over the four hours it took us to get to Antarctica, we demonstrated and explained these experiments for groups of students and other interested passengers.
Using a compass and a dip circle (a compass needle mounted sideways so that it could point downwards) we showed the students how the direction and strength of the Earth’s magnetic field changed as we neared the pole. The south magnetic pole actually lies off the coast of Antarctica, roughly in line with Adelaide, and more than 2,800 km north of the geographic pole. It actually lies outside the Antarctic circle, which is fortunate, because we flew right past the magnetic pole as we headed to the coast of Antarctica.
UWA PhD Candidate David Gozzard with some of the equipment that will be used on the flight to the South Pole. Credit: ICRAR.
Because of the movement of material within the Earth’s core, the south magnetic pole is currently moving northwest at a rate of about 15 km per year. It’s also getting weaker over time, and geophysicists expect that the Earth’s magnetic field will go through a reversal within the next 2,000 years. This has happened many times throughout Earth’s history, and even during the history of mankind. It will be an interesting time on Earth when the South (and North) magnetic poles are near the equator!
After magnetism, we moved on to cosmic rays. We used a device called an electroscope to demonstrate how physicist Victor Hess discovered cosmic rays in 1912, work for which he won the Nobel Prize. An electroscope contains a needle or some other indicator that registers the presence of static electricity. Electroscopes discharge faster (the needle returns to zero) in the presence of ionizing radiation. By taking an electroscope aloft in a balloon, Hess discovered that it discharged faster the higher he went. He correctly concluded that radiation levels were higher at higher altitudes and that the radiation was coming from outer space, hence “cosmic rays”. Cosmic rays are serious problem for space exploration, including manned missions to Mars.
Using a pair of Geiger counters, we showed that the density of cosmic rays in the plane was between five and ten times higher than on the ground in Perth. (At one point the reading was 30 times higher.) This was because we were flying at an altitude of 10 km, and so there was less air above us to block the cosmic rays from reaching us. Also, the Earth’s magnetic field acts like a funnel to pour the charged particles from the cosmic rays onto the magnetic poles, and it is these charged particles hitting the Earth’s atmosphere that causes the auroras. We were flying through an aurora — we just couldn’t see it in the daylight.
All too soon we had to pack away our equipment because the main tour was about to begin. Once we crossed the coast the Antarctic experts and explorers on board would guide us through what we saw.
The jumbo descended so we could get a better view of what was below, and the excitement on board was immense when the first iceberg was sighted.
The air was crystal clear and gave us brilliant views of stark white icebergs floating in the deep blue of the ocean. The number and density of icebergs grew quickly and within minutes we were over the sea ice. A few minutes later, we crossed the coast at Casey station, Australia’s main Antarctic research station. The station staff had just started their traditional Australia Day game of cricket out in the snow. They broke off to wave as the jumbo banked overhead.
We made a couple of laps of Casey so that everyone could get a good view before we headed west along the coast. We flew low over the Vanderford glacier and between the Bunger Hills and Bowman and Mill Islands before heading out to the Shackleton ice shelf. Every few minutes we were greeted with different scenery below. The textures of Antarctica vary widely, and each new feature was met with great excitement. We saw vast white plains of ice, and iceberg traffic jams in turquoise bays, and all along the way our Antarctic experts kept us entertained with information and stories about the land passing below.
Mirny, an old Russian research station, marked the mid-point of our journey and we turned around and retraced our route back to Casey, where we turned north and headed for home.
All of us were stunned by the beauty of the Antarctic continent. Back in Perth, the Kent Street students excitedly told their parents about what they had seen and what they had learned. They had some great stories to tell their friends at school on Monday morning.
Thank you to Antarctica Flights, the Qantas crew and the enthusiastic Antarctic experts for an amazing trip. Many thanks to Professor Ian McArthur and Lance Maschmedt at the UWA School of Physics & Astrophysics, and Pete Wheeler and Kirsten Gottschalk at the International Centre for Radio Astronomy Research for organizing the trip for Sarah and me and providing the equipment for the experiments. And a huge thank you to the Laby Foundation for this fantastic opportunity.
Links of interest
- Press release — icrar.org/southpole
- Geomagnetic reversal — theconversation.com/why-the-earths-magnetic-poles-could-be-about-to-swap-places-and-how-it-would-affect-us-71910
- Antarctica Flights — antarcticaflights.com.au