Ved hjelp av en kombinasjon av teleskoper, inkludert European Southern Observatorys Very Large Telescope (VLT), har astronomer avslørt et planetsystem som består av seks eksoplaneter, hvorav fem er låst i en sjelden rytme rundt stjernen sin. Forskerne mener systemet kan gi viktige ledetråder om hvordan planeter, inkludert de i solsystemet, dannes og utvikler seg. [...]
Sometime during the third century, a brilliant burst of light from the explosion of a massive star was visible from Earth.
If the supernova blast had flashed over the northern hemisphere, it might have been considered an evil omen. At that time, Western Civilization was in upheaval. The Roman Empire was beginning to crumble. An emperor was assassinated, followed by political upheavals, civil wars, and barbarian attacks.
But the violent supernova death could only be seen in [...]
How dark is the sky, and what does that tell us about the number of galaxies in the visible universe? Astronomers can estimate the total number of galaxies by counting everything visible in a Hubble deep field and then multiplying them by the total area of the sky. But other galaxies are too faint and distant to directly detect. Yet while we can’t count them, their light suffuses space with a feeble glow.
To measure that [...]
In 1995, the Hubble Space Telescope stared at a blank patch of the sky for 10 straight days. The resulting Deep Field image captured thousands of previously unseen, distant galaxies. Similar observations have followed since then, including the longest and deepest exposure, the Hubble Ultra Deep Field. Now, astronomers are looking ahead to the future, and the possibilities enabled by NASA’s upcoming Nancy Grace Roman Space Telescope.
The Roman Space Telescope will be able to photograph [...]
Galakser begynner å «dø» når de slutter å danne stjerner. Fram til nå har astronomer aldri klart å observere starten på denne prosessen i en fjern galakse. Men ved hjelp av Atacama Large Millimeter/Submillimeter Array (ALMA), der European Southern Observatory (ESO) er en partner, har astronomer sett en galakse kaste ut nesten halvparten av sin stjernedannende gass. Denne utkastingen skjer med en oppsiktsvekkende hastighet, tilsvarende 10 000 solmasser med gass per år. Galaksen mister raskt [...]
When NASA's Voyager 2 spacecraft flew by Neptune in 1989 after a nearly 3-billion-mile odyssey, astronomers expected to get a close-up look at a blue-green planet that seemed as featureless as a marble. Instead, they were shocked and intrigued to see a dynamic and turbulent world of whirling storms, including a giant feature dubbed the Great Dark Spot, looming in Neptune's far southern hemisphere.
The vortex was reminiscent of Jupiter's legendary Great Red Spot, a monstrous [...]