Chhetri et al. used ASKAP to make measurements of Inter-Planetary Scintillation (IPS) with 2.5 min observations around the Sun made at a solar elongation of 10 degrees. The 16 observations around the Sun (which is marked with yellow circle) are shown, with the Chhetri et al. paper based on the single observation highlighted by the red square in the plot.

Chhetri et al. present a catalogue of 131 compact (angular size less than 0.1 arcseconds) sources detected with ASKAP at 823 MHz via their Interplanetary Scintillation (IPS).  These measurements were made across the full ASKAP field of view of 35 square degrees, utilising all 36 Phased Array Feed (PAF) beams. The observations were made on 2 Feb 2023, with sixteen 2.5 min observations around the Sun made at a solar elongation of 10 degrees at the centre of the PAF footprint. The sources observed thus had solar elongations between 7.5 and 12.5 degrees. IPS is caused by the solar wind of charged particles, which streams away from the Sun. Observing 10 degrees away from the Sun ensures that radio emission from the Sun itself does not interfere with the observations. In the image above the position of the Sun is marked with a yellow circle, and the PAF footprints of the 16 observations shown. The pointing centre of the central PAF beam (beam 00) is shown in blue colour, and the other pointing centres of other beams are shown in grey. The paper describing the results is based on the single observation highlighted by the red square in the plot. This pilot study using test data is a pathfinder for a more comprehensive ASKAP IPS survey which is underway.