Space News & Blog Articles

Ever since physicist Freeman Dyson first proposed the concept in 1960, the “Dyson sphere” has been the holy grail of techno-signature hunters. A highly advanced civilization could build a “sphere” (or, in our more modern understanding, a “swarm” of smaller components) around their host star to harvest its entire energy output. We know, in theory at least, that such a swarm could exist - but what would it actually look like if we were able to observe one? A new paper available in pre-print on arXiv, and soon to be published in Universe from Amirnezam Amiri of the University of Arkansas digs into that question - and in the process discloses the types of stars that are the most likely to find them around.

Superliminous supernovae are miraculous events. For astronomers, they also provide a vital tool for measuring cosmic distances and the rate at which the Universe is expanding. As part of the Cosmic Distance Ladder, these incredibly bright stellar explosions are the "standard candles" for objects billions of light-years away. In a rare event, researchers from the University of Munich, using the Large Binocular Telescope (LBT) in Arizona, witnessed a superluminous supernova 10 billion light-years away that was far brighter than most explosions of its kind.

Satellite imaging is increasingly important to every field from crop monitoring to poverty reduction. So it’s no surprise that there have been more and more satellites launched to try to meet that growing demand. But with more satellites comes more risk for collision - and the debris field that comes after the collision. A new paper in Advanced in Space Research from John Mackintosh and his co-authors at the University of Manchester looks at how we might use mission design to mitigate some of the hazards of increasing the number of satellites even more.

Aging stars are prolific producers of dust, and the dust plays an important role in the cosmos. Their dust is ejected into the interstellar medium (ISM) where it is taken up in the next generation of stars and planets. This is how stars seed their environments with metals, elements heavier than hydrogen and helium, which are necessary for rocky planets and life to form.

Estimating a mass for a potentially hazardous asteroid (PHA) is perhaps the single most important thing to understand about it, after its trajectory. Actually doing so isn’t easy though, as the mass for objects in the tens to hundreds of kilometers in size are too small to have their mass calculated by traditional radio-frequency tracking techniques. A new paper from Justin Atchison of the Johns Hopkins University Applied Physics Laboratory and his co-authors proposes a method that could find the mass of asteroids even on the smaller end of that range, but will require precise coordination.

The Sun is trying to tell us something. In the first four days of February this year, it unleashed six powerful X-class solar flares in rapid succession including one classified X8.1, the strongest in several years. For most of us, that meant some disrupted radio signals, some spectacular aurora displays, and a reminder that our nearest star is not the steady, reliable lamp we sometimes take for granted. For solar physicists, it was confirmation that we are deep inside one of the most dangerous periods the Sun has produced in a generation.

It is one of the most famous questions in science, and it was asked, as legend has it, over lunch. Enrico Fermi, the physicist who helped build the first nuclear reactor and whose name graces a unit of length so small it makes an atom look generous, was chatting with colleagues about the possibility of alien life when he suddenly asked ‘where is everybody?’