Betelgeuse, one of the brightest and most famous stars in the northern night sky, has varied in brightness with an elusive pattern ever since observations began. Many theories exist as to why it ebbs and flows with apparently two distinct rhythms – one shorter and another around 2000 days long.

But just recently two independent astronomical teams have unveiled papers suggesting the existence of an orbital companion circling the red giant. About the size of our own sun, the “Betelbuddy” may whizz round Betelgeuse, almost skimming its surface, every 2000 days. And why haven’t we seen the Betelbuddy before? Because, from here, it would be a million times fainter than Betelgeuse itself, as one of the authors, and long-time Betelgeuse watcher, Andrea Dupree of Harvard and Smithsonian Centre for Astrophysics explains.

Back here on earth, Omar Yaghi of Berkeley, University of California and colleagues have been designing a new material that can scrub carbon dioxide out of the air in minutes. They have patented this type of Covalent Organic Framework (COF) and are hoping to scale up production such that a few hundred tonnes deployed around our biggest cities could solve our CO2 crisis.

But then what do you do with all those gigatonnes of CO2? Maybe one thing would be to use solar power to convert it into plant food. Robert Jinkerson and colleagues describe in the journal Joule a proposal to transform global food production into “Electro-Agriculture”, growing plants, fungi and algae on acetate made from solar energy. Their proposal would also shrink the global footprint of farming to allow more natural habitat.

And finally, Michael Frachetti of Washington University in St Louis has published an archaeological survey of two lost conurbations in the mountains of southern Uzbekistan that he and colleagues rediscovered in the last few years. He argues that the scale and complexity of these dwelling, and their location over 2000m, way above normal agricultural altitude mean we need to reconsider these stops on what would have been the Silk Road, around 600-1000 CE, perhaps even pointing at a very early industrial economy.

Presenter: Roland Pease Producer: Alex Mansfield with Andrew Lewis

(Image: Orion sink to Kashimayarigadake. Credit: Getty)