Space News & Blog Articles

One of the most stubborn issues in cosmology today concerns the Universe's rate of expansion. Scientists know it's expanding, but defining the rate of that expansion is challenging. The rate of expansion is called the Hubble Constant, after American astronomer Edwin Hubble, who discovered that the Universe is expanding in the 1920s.

Back in the earlier days of the internet, there was a viral video from a creator called Bill Wurtz called “the history of the entire world, i guess” which spawned a number of memorable memes, some of which are still in use to this day. One of those was a clip from the video where Wurtz states “The Sun is a deadly laser.” Apparently, that was more true than even he knew, as a new paper from Georgios Tsirvouils of the Luleå University of Technology in Sweden and his co-authors have shown experimental evidence that the Sun’s laser-like radiation is likely responsible for the death of a vast majority of closely-orbiting asteroids.

When the Sun erupts in its most violent flares, it doesn’t just hurl plasma and particles into space. These explosions also generate intense bursts of gamma radiation, the most energetic form of light in the universe. Solar physicists have detected these gamma ray signals for decades, yet the precise mechanism producing them remained frustratingly elusive. Now researchers at the New Jersey Institute of Technology have pinpointed the source.

Right now, as you read this sentence, roughly a trillion neutrinos are passing straight through your body. They slip through flesh and bone and even brain without leaving a trace, streaming through the entire planet as if it weren’t there at all. These ghost particles have earned their name through spectacular elusiveness, interacting so rarely with ordinary matter that detecting even one requires enormous underground detectors and considerable patience.

At the beginning of the exoplanet age, the goals were fairly simple. The first was to find as many of them as possible to flesh out our understanding of the exoplanet population. The second was to determine if any were in the habitable zones around their stars. The definition of a habitable zone was necessarily simple in the beginning. Any planet in the right distance range from its star to allow liquid surface water was considered to be in the habitable zone.

The universe occasionally produces flashes of light so bright and so blue that they outshine entire galaxies, then vanish within days. For years, astronomers studying these rare event, called luminous fast blue optical transients, or LFBOTs, debated their origin. Were they unusual supernovae, or something fundamentally different?

The thunderous roar that echoed across Huntsville, Alabama, on January 10 wasn't a rocket launch but something equally momentous: the end of an era. Two massive test stands that helped send humans to the Moon collapsed in carefully choreographed implosions, their steel frameworks crumbling in seconds after decades standing as monuments to American spaceflight achievement.

When stars at least thirty times the mass of our Sun reach the end of their lives, astronomers had assumed they simply winked out, collapsing silently into black holes under the force of gravity from which not even light can escape. No bright supernova explosion, no spectacular death throes, just a quiet gravitational implosion.

There is a fundamental tension in space exploration that has created ongoing debates for decades. By creating the infrastructure we need to explore other worlds, we damage them in some way, making them either less scientifically interesting or less “pristine,” which some would argue, in itself, is a bad thing. A new paper available in JGR Planets, from Francisca Paiva, a physicist at Instituto Superior Técnico, and Silvio Sinibaldi, the European Space Agency’s (ESA’s) planetary protection officer, argues that, in the Moon’s case at least, the problem is even worse than we originally thought.