Ms Angelica Waszewski

I am a PhD student at the Curtin Institute of Radio Astronomy with the International Centre for Radio Astronomy Research (ICRAR). Working alongside Dr John Morgan, Dr Rajan Chhetri, Dr Ramesh Bhat, and Prof Melanie Johnston-Hollitt, I am searching for coronal mass ejections (CMEs) and forecasting space weather events with interplanetary scintillation (IPS) using the Murchison Widefield Array (MWA).

Just as stars twinkle in the night sky because of atmospheric interference, compact radio sources light years away will twinkle due to turbulence in the solar wind, a phenomenon known as interplanetary scintillation (IPS). This very effect can be useful in both studying said radio sources and for making measurements of the solar wind. This also makes IPS very sensitive to intense changes in solar wind which could be caused by large space weather events, such as a coronal mass ejection where a literal part of the surface of the Sun is ejected into the solar system, a plasma with an embedded magnetic field, carrying with it highly charged particles.

Major space weather events, such as large solar flares and powerful CMEs, if aimed at Earth are a huge potential risk to our technology and our modern-day ways of living. One such devastating event has already occurred in 1859, where a major CME directed at Earth created the most intense geomagnetic storm in recorded history, named the Carrington event, after British astronomer Richard Carrington. This solar storm created strong global auroral displays spotted as close to the equator as Colombia, and caused sparks and fires at multiple telegraph stations, with some telegraph operators reporting they were shocked while touching their equipment. Similar less severe events have occurred again in 1921 and 1960, where widespread radio disruptions were reported. If another Carrington-like event were to hit Earth today, with our worldwide electrical systems it is estimated to cost US$0.6-2.6 trillion in damages to the US alone, and if major enough, the collapse of society itself. It is therefore not hard to understand that one of main objectives in studying solar activity is to predict not only the severity of these events, but the occurrence of them.

Although the Sun is closely monitored by other missions and projects such as NASA’s STEREO and ESA/NASA’s SOHO with LASCO, with the SWPC on constant look out for a CME’s Earth-impact likelihood, a large number of solar events are being missed, and those that are captured are all studied within close proximity of the Sun, which leads to gaps in humanity’s understanding of how these solar storms occur and behave. The expectation of my project is that not all MWA events will have been detected previously and that these measurements will be able to significantly refine our understanding of how the ejections evolve as they move further away from the Sun. Using both the MWA’s IPS data, alongside our other ancillary data such as dual-frequency solar imaging, the main goal is to reconstruct the inner heliosphere as accurately as possible, with an additional objective of extracting polarimetry to study the magnetic fields in remote parts of the heliosphere.