First measurement of interplanetary scintillation with the ASKAP radio telescope: implications for space weather

TL;DR

This paper demonstrates the potential of ASKAP radio telescope to observe interplanetary scintillation and CMEs, enabling earlier space weather predictions by leveraging its wide field of view and rapid response capabilities.

Contribution

First measurement of interplanetary scintillation with ASKAP, showing its potential for early CME detection and space weather monitoring using a targeted observational approach.

Findings

ASKAP can observe within 10 degrees of the Sun.

A targeted 'Target Of Opportunity' approach can detect most CMEs.

ASKAP complements lower-frequency instruments like MWA.

Abstract

We report on a measurement of interplanetary scintillation (IPS) using the Australian Square Kilometre Array Pathfinder (ASKAP) radio telescope. Although this proof-of-concept observation utilised just 3 seconds of data on a single source, this is nonetheless a significant result, since the exceptional wide field of view of ASKAP, and this validation of its ability to observe within 10 degrees of the Sun, mean that ASKAP has the potential to observe an interplanetary coronal mass ejection (CME) after it has expanded beyond the field of view of white light coronagraphs, but long before it has reached the Earth. We describe our proof of concept observation and extrapolate from the measured noise parameters to determine what information could be gleaned from a longer observation using the full field of view. We demonstrate that, by adopting a `Target Of Opportunity' (TOO) approach, where the telescope is triggered by the detection of a CME in white-light coronagraphs, the majority of interplanetary CMEs could be observed by ASKAP while in an elongation range $<$30 degrees. It is therefore highly complementary to the colocated Murchison Widefield Array, a lower-frequency instrument which is better suited to observing at elongations $>$20 degrees.