This week at Davis: 4 April 2025

Much as the Earth’s atmosphere is a chaotic interaction of winds, pressure systems and temperature gradients that can lead to intense storms, the roiling ball of nuclear plasma we know as the Sun experiences its own weather patterns and tempests. When the Sun is particularly active, solar flares, coronal mass ejections and other phenomena can fling charged particles outward at high speed – occasionally aimed right at us. In 2025 we are close to a ‘solar maximum’ in the 11 year cycle of the Sun’s activity.

These particles, through interactions with Earth’s magnetic field and upper atmosphere, can knock out satellites and interfere with radio communication and GPS navigation, with the most severe geomagnetic storms potentially damaging electrical grids on a wide scale. Studying this space weather can help us forecast activity, protect infrastructure and better understand the physics of the atmosphere and solar system.

As the wintering electronics engineer here at Davis, I am responsible for an array of scientific instrumentation and experiments, some of which are dedicated to measuring these effects:

• The magnetometer detects the change in Earth’s magnetic field as it bends in concert with the Sun
• The ionosonde and riometers measure the radio reflectivity and absorption of the ionosphere as the electron density fluctuates
• All-sky cameras capture a full-colour 180 degree image of the sky while dedicated auroral cameras photograph the specific wavelengths emitted by excited oxygen and nitrogen in the upper atmosphere

Data from these instruments is sent to the Australian Space Weather Forecasting Centre (part of the Bureau of Meteorology) and researchers around the world.

With all that said, apart from a few specific fields involving satellites, navigation and radio communication, space weather won’t affect your day to day life. But, for those living at high latitudes such as us, the forecast might keep you up at night – in a good way!

The Earth’s magnetic field funnels the majority of those charged particles from the Sun toward the poles where, above 80 km in altitude, they collide with oxygen atoms and nitrogen molecules, exciting them to a higher energy state. When they release this energy it is as specific red, green and violet wavelengths of light that result in what we see as an ‘aurora’ – which can appear from a subtle glow on the horizon to rippling bands of vivid light overhead.

I am a keen photographer and as a Tasmanian resident have been lucky enough to see quite a few auroras from the island state. I’ve travelled south with the Australian Antarctic Program in prior summers – but, as fantastic an experience that was in so many ways, 24 hours of daylight is not particularly conducive to astrophotography. One reason I was especially excited for a winter deployment was the opportunity to capture the aurora australis from the best vantage point on the planet!

I was well prepared coming down to Davis with a frankly excessive collection of cameras, tripods and technology, all with the goal of taking stunning panoramas and timelapse videos. But as it happened my first aurora in Antarctica would be at 2am in the midst of a multi-day hike in the Vestfold Hills to see the Sørsdal Glacier, my camera precariously perched on a rock as I gave an ad-hoc photography lesson to my fellow expeditioners.

As the temperatures drop and days wane in length here at Davis, we have been treated to a solid week of overhead aurora action, even with only moderate solar activity. I have fallen into the role of de-facto aurora forecaster for other expos and am excited to see more vivid and varied light shows, even if it might leave me sleep deprived!

For more information about auroras and how they have been observed in Antarctica, see https://www.antarctica.gov.au/news/explore-antarctica/auroras/

James Newlands - Electronics Engineer for the Antarctic Climate Program