“The wobbling shadow of the M87* black hole” is a video made by astronomers working on the Event Horizon Telescope (EHT), which in 2019 found the first direct visual evidence of a black hole and its “shadow”. The video above is an animation of three years in the life of the black hole M87* as its shadow wobbles. It shows extremely hot and turbulent gas swirling around the event horizon of the black hole before plunging into the abyss.
The animation is done in the wavelength of radio waves that EHT is sensitive to and towards the end of the video the image is blurred to simulate the limited resolution of the EHT.
Baking a pie
One of the most remarkable things about the plethora of known exoplanets is that many of them orbit extremely close to their stars while travelling at extremely high speeds. K2-315b is no exception, moving at a blistering 81 km/s in a tight orbit around a cool star that is about one fifth the size of the Sun. The exoplanet itself appears to be about the same size as Earth, but is expected to have a surface temperature of about 180 °C. That is about the right temperature for baking a pie. But that is not why K2-315b has been dubbed the “π planet” – it takes just 3.14 Earth days to orbit its star.
K2-315b was studied by Prajwal Niraula and colleagues using the NASA Kepler Space Telescope’s K2 mission and the SPECULOOS network of ground-based telescopes. They described their observations in The Astronomical Journal.
Science is a human endeavour, so it is not surprising that the scientific literature can sometimes reflect social attitudes that were prevalent when the papers were written. In “Science journals are purging racist, sexist work. Finally”, Adam Marcus and Ivan Oransky of Retraction Watch applaud the removal of papers published less than a decade ago “that have been called out for both their content and their lack of scientific rigour”. They also call for the more aggressive retraction of papers that although not based on repugnant ideas, are nonetheless wrong and pose threats to the credibility of the scientific literature.