Organic compounds can form through simple chemistry alone — making the search for true biosignatures trickier than it seems. Posted on Big Think. Read it Here: Biosignatures? Why organics on Mars don’t necessarily signal life — Big Think
Category: space – Page 12
New radio halo discovered with MeerKAT
Using the MeerKAT radio telescope, an international team of astronomers has performed observations of a galaxy cluster designated SPT-CLJ2337−5942. The observational campaign revealed the presence of an ultra-steep spectrum radio halo in this cluster. The finding is presented in a paper published Sept. 9 on the arXiv preprint server.
Mapping the universe, faster and with the same accuracy
If you think a galaxy is big, compare it to the size of the universe: it’s just a tiny dot which, together with a huge number of other tiny dots, forms clusters that aggregate into superclusters, which in turn weave into filaments threaded with voids—an immense 3D skeleton of our universe.
If that gives you vertigo and you’re wondering how one can understand or even “see” something so vast, the answer is: it isn’t easy. Scientists combine the physics of the universe with data from astronomical instruments and build theoretical models, such as EFTofLSS (Effective Field Theory of Large-Scale Structure). Fed with observations, these models describe the “cosmic web” statistically and allow its key parameters to be estimated.
Models like EFTofLSS, however, demand a lot of time and computing resources. Since the astronomical datasets at our disposal are growing exponentially, we need ways to lighten the analysis without losing precision. This is why emulators exist: they “imitate” how the models respond, but operate much faster.
Observations investigate the nature of a newly discovered odd radio circle
Astronomers from Ruhr University Bochum in Germany and elsewhere have conducted radio spectropolarimetric observations of a recently identified odd radio circle designated ORC J0356–4216. Results of the observational campaign, presented Sept. 5 on the arXiv pre-print server, shed more light on the nature of this object.
The so-called odd radio circles (ORCs) are mysterious gigantic rings of radio waves and their origin is still unexplained. They are highly circular and bright along the edges at radio wavelengths but they cannot be observed at visible, infrared or X-ray wavelengths. To date, only a few objects of this type have been identified, hence very little is known about their nature.
ORC J0356–4216 was identified in October 2023 with the MeerKAT radio telescope and shortly after its discovery, a group of astronomers led by Ruhr University Bochum’s Sam Taziaux, performed radio spectropolarimetry of this source using the Australian SKA Pathfinder (ASKAP) and MeerKAT to investigate its properties and nature.