Category Astronomy/Space

Some stars appear to defy time itself. Nestled within ancient star clusters, they shine bluer and brighter than their neighbors, looking far younger than their true age. Known as blue straggler stars, these stellar oddities have puzzled astronomers for more than 70 years. Now, new results using the NASA/ESA Hubble Space Telescope are finally revealing how these “forever young” stars come to be and why they thrive in quieter cosmic neighborhoods.

Why blue stragglers puzzle astronomers
Blue straggler stars stand out in old star clusters because they appear hotter, more massive and younger than stars that should all have formed billions of years ago...

New observations reveal how solar flares really ignite—and why they can be so powerful. Solar Orbiter has captured the clearest evidence yet that a solar flare grows through a cascading “magnetic avalanche.” Small, weak magnetic disturbances rapidly multiplied, triggering stronger and stronger explosions that accelerated particles to extreme speeds. The process produced streams of glowing plasma blobs that rained through the Sun’s atmosphere long after the flare itself.

Much like a snow avalanche that starts with a small shift before cascading downhill, new observations show that solar flares begin with subtle magnetic disturbances that rapidly intensify...

WASP-121b, a scorching gas giant orbiting its star every 30 hours, is literally bleeding its atmosphere into space. Astronomers from the University of Geneva (UNIGE), the National Centre of Competence in Research PlanetS, and the Trottier Institute for Research on Exoplanets (IREx) at the University of Montreal (UdeM) have made a major breakthrough using the James Webb Space Telescope (JWST). For the first time, researchers have followed gas escaping from an exoplanet’s atmosphere continuously over a full orbit around its star.

The observations revealed an unexpected and dramatic result. The gas giant WASP-121b is surrounded by not one, but two enormous streams of helium that stretch across more than half of its orbit...

Over the years, passing spacecraft have observed mystifying weather patterns at the poles of Jupiter and Saturn. The two planets host very different types of polar vortices, which are huge atmospheric whirlpools that rotate over a planet’s polar region. On Saturn, a single massive polar vortex appears to cap the north pole in a curiously hexagonal shape, while on Jupiter, a central polar vortex is surrounded by eight smaller vortices, like a pan of swirling cinnamon rolls.

Given that both planet...