This is a bonus article for paying subscribers. Thank you so much for your support, it means a lot to me and helps me to keep writing. I’m planning to offer more bonus content for you over the coming months and I already have a couple of articles in draft form. If there any questions you’d like me to take a look at, or any topics you’d like me to cover, then don’t hesitate to comment or email me and I’ll see what I can do! We are fortunate to live in an era where our eyes on the universe are more powerful than ever before. Modern telescopes peer across vast distances, look back billions of yea ..read more

Rafale pilots guard and watch the launch of the Ariane 6. Image credit: The French Ministère des Armées. Over a period of ten years the upcoming Rubin Observatory expects to see somewhere between three and four million supernovae. That, needless to say, is a lot: the figure implies a discovery rate of roughly a thousand stellar explosions every single day.  Each of those supernovae will appear as a flash of light suddenly brightening and then fading away over a matter of months. All are powerful events, bright enough to outshine a galaxy, and visible across millions of light years. But ..read more

Young stars shine amidst pillars of gas in the Orion Nebula. Image credit: NASA, ESA, M. Robberto ( Space Telescope Science Institute/ESA) and the Hubble Space Telescope Orion Treasury Project Team Long ago, the story goes, our solar system had a fifth giant planet. In form this world may have looked like Neptune - that's to say, it was an ice giant, bluish in colour and held perhaps twenty times the mass of Earth. It probably lay somewhere between Saturn and Uranus, though back then the gas giants orbited much closer to the Sun, and the outer planets might have been arranged in a different ..read more

Jupiter, with the Great Red Spot, as seen by the Cassini spacecraft. Image credit: NASA/JPL-Caltech/SSI/CICLOPS/Kevin M. Gill According to the official story, the Great Red Spot of Jupiter has been around for centuries. It was there, they say, when Robert Hooke peered through his telescope in May 1664, and then when the artist Donato Creti painted the planet in 1711. It was definitely there in February 1979, when Voyager 1 flew past and snapped a photo, and still there in 2022, when the Webb captured a magnificent view of the giant planet. Except, perhaps it wasn’t. Jupiter’s Great Red Spot ..read more

Earthrise, photographed by NASA astronaut William Anders, who passed away last week. Though the Moon waxes and wanes in our sky, shifting from new moon to full moon and back again, it always presents the same unchanging face to us. Like most heavenly bodies, the Moon does spin, yet it rotates at precisely the same rate as it revolves around the Earth: turning in such a way that one face is always pointing towards us, and the other is always facing away. That second face - the one forever hidden to us - is known as the dark, or far, side of the Moon. Until 1959, when a Soviet spacecraft sent ..read more

Jinzhu Ji, Dijun Guo, Jianzhong Liu, et al. (2022) The 1:2,500,000-Scale Geologic Map of the Global Moon Once upon a time, Earth, Mars and Venus all had plenty of water. Earth still has oceans, of course, which puts their past existence in little doubt. Studies of Mars have found clear signs of ancient shorelines, flowing rivers and even of tsunamis striking coastlines. The Red Planet, we can say with some confidence, was once Blue.  But what about Venus? Today that planet is utterly dry, with no water on its surface and only a trace amount in its atmosphere. Neither is there much sign ..read more

Hubble spies a newborn star shining behind a cocoon of dust. Image credit: NASA, ESA, and K. Stapelfeldt (NASA JPL); Image Processing: Gladys Kober (NASA/Catholic University of America) On October 8, 2022 a sudden wave of energy crashed over Voyager I, momentarily lit up its sensors, and then faded away. Nineteen hours later the same wave reached the orbits of Earth and Mars, swept across two dozen telescopes, and carried on, vanishing into the icy depths of space. Astronomers soon realised the wave had been remarkably powerful. Telescopes designed to hunt for bursts of this kind were blinde ..read more

Totality over North America. Image Credit: NASA/Keegan Barber Until 1998 we thought the universe, on a large scale at least, was dominated by gravity. This is the force, after all, that binds planets to stars, stars to galaxies and galaxies to clusters. But gravity is also an attractive force, and so it should, over a long period of time, tend to pull things together. If the universe happened to be expanding, which we knew it was, then gravity should act to slow it down, and eventually, perhaps, to send it into reverse. And then, after carefully studying distant supernovae, astronomers concl ..read more

Chandra, Webb and Hubble worked together to create this image of Cassiopeia A, the three hundred year old remains of a supernova. Image credit: X-ray: NASA/CXC/SAO; Optical: NASA/ESA/STScI; IR: NASA/ESA/CSA/STScI/Milisavljevic et al., NASA/JPL/CalTech; Image Processing: NASA/CXC/SAO/J. Schmidt and K. Arcand Once every eighty years the star T Coronae Borealis blows up. We know this because we’ve seen it happen at least twice - the first time in 1866, when the star was officially discovered, and another in 1946, when telescopes studied the exploding star in more detail. It has probably happene ..read more

Strange rock formations litter the western end of the Valles Marineris on Mars, like this mesa seen by NASA’s Mars Reconnaissance Orbiter. A giant volcano may lurk there too. Image credit: NASA/JPL-Caltech/Univ. of Arizona The facts are these. At a little past three in the morning of January 9, 2014, something exploded over the western Pacific Ocean. The event was picked up by military sensors, which showed a fast moving object had struck the Earth and then detonated in the atmosphere. It was, in all probability, a small asteroid encountering our world. This is not controversial. Such things ..read more