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Historically, astronomy has prioritized visuals to present information, with scientists and communicators overlooking the critical need to communicate astrophysics with blind or low-vision audiences and provide novel channels for sighted audiences to process scientific information. This study sonified NASA data of three astronomical objects presented as aural visualizations, then surveyed blind or low-vision and sighted individuals to elicit feedback on the experience of these pieces as it relates to enjoyment, education, and trust of the scientific data. Data analyses from 3,184 sighted or blind or low-vision survey participants yielded significant self-reported learning gains and positive experiential responses. Results showed that astrophysical data engaging multiple senses could establish additional avenues of trust, increase access, and promote awareness of accessibility in sighted and blind or low-vision communities., Comment: Published in Frontiers in Communication on March 13th 2024. 15 pages, 9 figures, 2 tables. Supplemental data available through Frontiers publication. Accessible screen-reader version: https://docs.google.com/document/d/1IdroqbdtULo2OQFaqGw20NRVD-sLYEKBUPWnmxZ9gH0/edit?usp=sharing Press release: https://www.frontiersin.org/news/2024/03/25/communication-nasa-scientists-space-data-sounds

The Australian SKA Pathfinder (ASKAP) radio telescope has carried out a survey of the entire Southern Sky at 887.5MHz. The wide area, high angular resolution, and broad bandwidth provided by the low-band Rapid ASKAP Continuum Survey (RACS-low) allow the production of a next-generation rotation measure (RM) grid across the entire Southern Sky. Here we introduce this project as Spectral and Polarisation in Cutouts of Extragalactic sources from RACS (SPICE-RACS). In our first data release, we image 30 RACS-low fields in Stokes $I$, $Q$, $U$ at 25'' angular resolution, across 744 to 1032MHz with 1MHz spectral resolution. Using a bespoke, highly parallelised, software pipeline we are able to rapidly process wide-area spectro-polarimetric ASKAP observations. Notably, we use 'postage stamp' cutouts to assess the polarisation properties of \ncomponents\ radio components detected in total intensity. We find that our Stokes $Q$ and $U$ images have an rms noise of ~80$\mu$Jy/PSF, and our correction for instrumental polarisation leakage allows us to characterise components with >1% polarisation fraction over most of the field of view. We produce a broadband polarised radio component catalogue that contains \nrms\ RM measurements over an area of ~1300deg^2 with an average error in RM of 1.6+1.1-1.0rad/m^2, and an average linear polarisation fraction 3.4+3.0-1.6%. We determine this subset of components using the conditions that the polarised signal-to-noise ratio is $>8$, the polarisation fraction is above our estimated polarised leakage, and the Stokes $I$ spectrum has a reliable model. Our catalogue provides an areal density of $4\pm2$ RMs/deg^2; an increase of $\sim4$ times over the previous state-of-the-art (Taylor et al. 2009). Meaning that, having used just 3% of the RACS-low sky area, we have produced the 3rd largest RM catalogue to date. This catalogue has broad applications for studying..., Comment: 42 pages, 24 figures, 6 tables. Accepted for publications in PASA

The phenomenon of sub-pulse drifting is an important single-pulse phenomenon that can potentially provide important insights into the elusive radio emission mechanism in pulsars. We analyze the frequency behaviour of the single pulses of B0818-41, observed from 300 to 500 MHz (Band 3 of the uGMRT), and compare it to the evolution of the average profile to place constraints on the geometry of the pulsar's emission beam. We show that a circular carousel of discrete beamlets, where each beamlet has radial symmetry, is not consistent with the observed behaviour, and describe an alternative, consistent range of possible elliptical carousel geometries. We also combine the uGMRT data with some archival MWA observations and several other published profiles to characterize the profile evolution across a frequency range spanning ~170 MHz to ~1.4 GHz.

This pilot study evaluated a novel professional development (PD) model designed to prepare K-12 educators in high-need, rural school districts to teach evidence-based argument writing. The PD showed teachers how to engage students in discussions about visual art using Visual Thinking Strategies to enhance students' argumentation writing. Twenty intervention teachers completed the professional development program and conducted lessons in Visual Thinking Strategies and argument writing. Intervention teachers, relative to 34 comparison teachers, improved on their perceived knowledge of critical thinking concepts, ability to teach critical thinking concepts, knowledge of concepts related to argument writing and their actual ability to perceive and analyze artistic work and understand characteristics used to convey intent and meaning (Hedges's g > 0.50). Students in the intervention condition (N = 210 in K-11) improved their argument writing skills. Given the quasi-experimental design and small sample size, these findings should be viewed with caution but suggest promise. [This paper was published in "The Elementary School Journal" 2020 (EJ1270199).]

We present results from a search for the HI 21-cm line in absorption towards 16 bright radio sources with the 6-antenna commissioning array of the Australian Square Kilometre Array Pathfinder (ASKAP). Our targets were selected from the 2-Jy sample, a flux-limited survey of the southern radio sky with extensive multi-wavelength follow-up. Two sources were detected in HI absorption including a new detection towards the bright FRII radio galaxy PKS 0409-75 at a redshift of z=0.674. The HI absorption line is blueshifted by ~3300 km/s compared to the optical redshift of the host galaxy of PKS 0409-75 at z=0.693. Deep optical imaging and spectroscopic follow-up with the GMOS instrument on the Gemini-South telescope reveal that the HI absorption is associated with a galaxy in front of the southern radio lobe with a stellar mass of $3.2 - 6.8 \times 10^{11}M_\odot$, a star-formation rate of $\sim 1.24 M_\odot$ yr$^{-1}$ and an estimated HI column density of $2.16\times10^{21}$ cm$^{-2}$, assuming a spin temperature of $T_{\rm spin}=500$ K and source covering factor of $C_{\rm f}=0.3$. Using polarisation measurements of PKS 0409-75 from the literature we estimate the magnetic field of the absorbing galaxy to be ~14.5$\mu$G, consistent with field strengths observed in nearby spiral galaxies, but larger than expected for an elliptical galaxy. Results from this pilot study can inform future surveys as new wide-field telescopes allow us to search for 21-cm HI absorption towards all bright radio sources as opposed to smaller targeted samples., Comment: 14 pages, 6 figures, accepted for publication in MNRAS