We present new Australia Telescope Compact Array (ATCA) radio observations towards N 49, one of the brightest extragalactic supernova remnants (SNRs) located in the Large Magellanic Cloud (LMC). Our new and archival ATCA radio observations were analysed along with Chandra X-ray data. These observations show a prominent ‘bullet’ shaped feature beyond the southwestern boundary of the SNR. Both X-ray morphology and radio polarisation analysis support a physical connection of this feature to the SNR. The ‘bullet’ feature’s apparent velocity is estimated at $\sim$1 300 km s$^{-1}$, based on its distance ($\sim$10 pc) from the remnant’s geometric centre and estimated age ($\sim$7 600 yr). we estimated the radio spectral index, $\alpha= -0.55 \pm 0.03$ which is typical of middle-age SNRs. Polarisation maps created for N 49 show low to moderate levels of mean fractional polarisation estimated at 7$\pm$1% and 10$\pm$1% for 5.5 and 9 GHz, respectively. These values are noticeably larger than found in previous studies. Moreover, the mean value for the Faraday rotation of SNR N 49 from combining CABB data is 212$\pm$65 rad m$^{-2}$ and the maximum value of RM is 591$\pm$103 rad m$^{-2}$.

This study considers the role played by Teotihuacan in the emergence of the office of the Classic Maya ajawtaak, or ‘lords’. I argue that the synthesis of this office at the site of Tikal was influenced by the building of Teotihuacan's Pyramid of the Feathered Serpent between about 180 and 230 ce. Prior to and in concert with this building's construction, Teotihuacanos orchestrated the sacrifice of an estimated 200 or more individuals, some number of whom resided beyond the Basin of Mexico before burial. Osteological traits consistent with origins in the Maya region are present among these sacrifices. The Pyramid of the Feathered Serpent features mirror and obsidian icons, which later grew to prominence in the self-presentations of the ajawtaak. I note that around the time of this monument's construction, Tikal's obsidian corpus changed in ways that paralleled similar, earlier changes that had occurred to obsidian procurement strategies at Teotihuacan. I conclude that from about 200 ce, some Classic ajawtaak observed the religion that cohered with the building of Teotihuacan's Temple of the Feathered Serpent. The ajawtaak occupied a unique positionality in Early Classic Mesoamerica that was neither essentially Teotihuacan nor essentially Maya, but a dynamic syncretism of the two ethnicities.

We report the discovery of a bow-shock pulsar wind nebula (PWN), named Potoroo, and the detection of a young pulsar J1638$-$4713 that powers the nebula. We present a radio continuum study of the PWN based on 20-cm observations obtained from the Australian Square Kilometre Array Pathfinder (ASKAP) and MeerKAT. PSR J1638$-$4713 was identified using Parkes radio telescope observations at frequencies above 3 GHz. The pulsar has the second-highest dispersion measure of all known radio pulsars (1 553 pc cm$^{-3}$), a spin period of 65.74 ms and a spin-down luminosity of $\dot{E}=6.1\times10^{36}$ erg s$^{-1}$. The PWN has a cometary morphology and one of the greatest projected lengths among all the observed pulsar radio tails, measuring over 21 pc for an assumed distance of 10 kpc. The remarkably long tail and atypically steep radio spectral index are attributed to the interplay of a supernova reverse shock and the PWN. The originating supernova remnant is not known so far. We estimated the pulsar kick velocity to be in the range of 1 000–2 000 km s$^{-1}$ for ages between 23 and 10 kyr. The X-ray counterpart found in Chandra data, CXOU J163802.6$-$471358, shows the same tail morphology as the radio source but is shorter by a factor of 10. The peak of the X-ray emission is offset from the peak of the radio total intensity (Stokes $\rm I$) emission by approximately 4.7$^{\prime\prime}$, but coincides well with circularly polarised (Stokes $\rm V$) emission. No infrared counterpart was found.

Drawing upon iconological theory, this article argues that mirrors and blood were regarded as a conceptually linked pair within the imperial ideology of Teotihuacan, Mexico from the second century onward. The relationship between blood and mirrors is shown to have codified with the construction of the Pyramid of the Feathered Serpent, Teotihuacan's third largest edifice. This monument's facade was adorned with hundreds of monumental sculptures of oracular mirrors, some number of which incorporated actual mirrors formed of obsidian. I demonstrate that the Teotihuacan mirror sign took obsidian, a form of black volcanic glass that was intensively worked in the city, as a key referent. This monument was also the site of a historically large human sacrifice of more than 200 individuals, an event argued here to have involved bloodletting with obsidian knives and blades. I note that Teotihuacan interest in the mirror icon increased in concert with the city's residents’ application of the reflective material of obsidian to warring and other blood-spilling behaviors. The mirror icon evoked both obsidian as a radiant material, as well as obsidian's potential for application to forceful martial actions. The article concludes that this icon in part signified imperial force, which was made real through the weaponization of the smoking glass.