Jandangga 2023 ASKAP update

April’s solar eclipse in WA caused much excitement, with people travelling from all over the world to witness it. Although we only experienced a partial eclipse at Inyarrimanha Ilgari Bundara, our Murchison Radio-astronomy Observatory, our astronomers took full advantage of the rare event to conduct some experimental observations using our ASKAP radio telescope.

For ASKAP, the sun is the strongest radio source in the sky – when it’s above the horizon. Radio observations are particularly sensitive to active regions on the surface of the Sun (like sunspots) and can be used for studying the structure and activity of these regions, while also helping us learn more about the Sun’s magnetic field.

a black circle covers a fiery red circle

The Moon nearly covers the Sun during the 2023 Solar Eclipse, as seen by the ASKAP radio telescope

The Moon nearly covers the Sun during the solar eclipse, as seen through ASKAP’s radio eyes. Credit: Emil Lenc

At radio wavelengths, ASKAP can also study the solar wind: the continuous flow of charged particles that escape from the from the sun’s atmosphere and travel out through the solar system at speeds of up to 400 km/s. The solar wind is an important part of space weather, since it can cause auroras, geomagnetic storms, and other disruptions to Earth’s atmosphere and magnetic field.

During April’s partial solar eclipse, astronomers used ASKAP to study the properties of radio sources that appear close to the Sun. These sources are normally washed out by the Sun’s brightness – but when the Moon blocks light from the Sun during an eclipse, they become visible and can be studied in great detail. The background sources ‘twinkle’ in response to changes in the solar wind, and their behaviour can be used to determine key factors in the wind’s composition.

We prepared a special program with ASKAP for observing during the eclipse and used a newly-developed high time resolution instrument, which is a little like a slow motion camera. It will take some time to figure out what the results show, but the data should help us plan future experiments that can be done anytime, not just during a solar eclipse.

We’re excited about the possibilities that this research opens up, and by studying the solar wind, we can learn more about how the sun interacts with the rest of the solar system.

A fuzzy red and black animated timelapse image shows a partial eclipse of the sun

A timelapse image of the partial solar eclipse, captured by the ASKAP radio telescope. Credit: Emil Lenc

The eclipse research was a special event, but regular ASKAP observing still continues and is still making headlines! A recent study into fast radio bursts has shown us that these strange intergalactic phenomena are no closer to being understood and may be more varied that we originally thought! Read the full story on our CSIRO news page.

And ASKAP detected a cool star – it is about the same temperature as a pizza oven! That story is also on our CSIRO news page.

Aidan Hotan, ASKAP Principal Research Scientist, CSIRO and

James Chesters, ATNF Communications Advisor, CSIRO