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We present the Pilot Survey Phase 2 data release for the Wide-field ASKAP L-band Legacy All-sky Blind surveY (WALLABY), carried-out using the Australian SKA Pathfinder (ASKAP). We present 1760 H i detections (with a default spatial resolution of 30′′) from three pilot fields including the NGC 5044 and NGC 4808 groups as well as the Vela field, covering a total of 
$\sim 180$ deg
$^2$ of the sky and spanning a redshift up to 
$z \simeq 0.09$. This release also includes kinematic models for over 126 spatially resolved galaxies. The observed median rms noise in the image cubes is 1.7 mJy per 30′′ beam and 18.5 kHz channel. This corresponds to a 5
$\sigma$ H i column density sensitivity of 
$\sim 9.1\times10^{19}(1 + z)^4$ cm
$^{-2}$ per 30′′ beam and 
$\sim 20$ km s
$^{-1}$ channel and a 5
$\sigma$ H i mass sensitivity of 
$\sim 5.5\times10^8 (D/100$ Mpc)
$^{2}$ M
$_{\odot}$ for point sources. Furthermore, we also present for the first time 12′′ high-resolution images (“cut-outs”) and catalogues for a sub-sample of 80 sources from the Pilot Survey Phase 2 fields. While we are able to recover sources with lower signal-to-noise ratio compared to sources in the Public Data Release 1, we do note that some data quality issues still persist, notably, flux discrepancies that are linked to the impact of side lobes associated with the dirty beams due to inadequate deconvolution. However, in spite of these limitations, the WALLABY Pilot Survey Phase 2 has already produced roughly a third of the number of HIPASS sources, making this the largest spatially resolved H i sample from a single survey to date.
The Vela pulsar (J0835
$-$4510) is known to exhibit variations in Faraday rotation and dispersion on multi-decade timescales due to the changing sightline through the surrounding Vela supernova remnant and the Gum Nebula. Until now, variations in Faraday rotation towards Vela have not been studied on timescales less than around a decade. We present the results of a high-cadence observing campaign carried out with the Aperture Array Verification System 2 (AAVS2), a prototype SKA-Low station, which received a significant bandwidth upgrade in 2022. We collected observations of the Vela pulsar and PSR J0630
$-$2834 (a nearby pulsar located outside the Gum Nebula), spanning 
$\sim$1 and 
$\sim$0.3 yr, respectively, and searched for linear trends in the rotation measure (RM) as a function of time. We do not detect any significant trends on this timescale (
$\sim$months) for either pulsar, but the constraints could be greatly improved with more accurate ionospheric models. For the Vela pulsar, the combination of our data and historical data from the published literature have enabled us to model long-term correlated trends in RM and dispersion measure (DM) over the past two decades. We detect a change in DM of 
$\sim$0.3 
$\mathrm{cm}^{-3}\,\mathrm{pc}$ which corresponds to a change in electron density of 
$\sim$
$10^5\,\mathrm{cm}^{-3}$ on a transverse length scale of 
$\sim$1–2 au. The apparent magnetic field strength in the time-varying region changes from 
$240^{+30}_{-20}\,\mu\mathrm{G}$ to 
$-6.2^{+0.7}_{-0.9}\,\mu\mathrm{G}$ over the time span of the dataset. As well as providing an important validation of polarimetry, this work highlights the pulsar monitoring capabilities of SKA-Low stations, and the niche science opportunities they offer for high-precision polarimetry and probing the microstructure of the magneto-ionic interstellar medium.
Observing stars and satellites in optical wavelengths during the day (optical daytime astronomy) has begun a resurgence of interest. The recent dramatic dimming event of Betelgeuse has spurred interest in continuous monitoring of the brightest variable stars, even when an object is only visible during the day due to their proximity to the Sun. In addition, an exponential increase in the number of satellites being launched into low Earth orbit in recent years has driven an interest in optical daytime astronomy for the detection and monitoring of satellites in space situational awareness (SSA) networks. In this paper we explore the use of the Huntsman Telescope as an optical daytime astronomy facility, by conducting an exploratory survey using a pathfinder instrument. We find that an absolute photometric accuracy between 1–10% can be achieved during the day, with a detection limit of V band 4.6 mag at midday in sloan 
$g,$ and 
$r,$ wavelengths. In addition, we characterise the daytime sky brightness, colour, and observing conditions in order to achieve the most reliable and highest signal-to-noise observations within the limitations of the bright sky background. We undertake a 7-month survey of the brightness of Betelgeuse during the day and demonstrate that our results are in agreement with measurements from other observatories. Finally we present our preliminary results that demonstrate obtaining absolute photometric measurements of the International Space Station during the day.
