'Inside it, you have the part of the galaxy that is still actively building itself with ongoing star formation. Outside it, you have a disc region populated almost entirely by stars that have drifted there from elsewhere.'
When that new knowledge arrives, we inevitably attempt to integrate it into our pre-existing framework, and that isn't always a smooth process. Sometimes, our foundation is riddled with misconceptions, misunderstandings, or prior teaching that were outright wrong; we have to correct and 'unlearn' those ways of thinking before we can progress.
A metastable or 'false' vacuum is a hypothetical state that seems stable but hasn't actually reached its most stable state yet, posing a potential doomsday threat.
The new images of the Sombrero Galaxy, captured by the 570-megapixel Dark Energy Camera, reveal its bright core amid 2,000 globular star clusters tightly bound by gravity.
A bright star in a nearby galaxy has essentially vanished. Astronomers believe that it died and collapsed in on itself, transforming into the eerie cosmic phenomenon known as a black hole. "It used to be one of the brightest stars in the Andromeda galaxy," says Kishalay De, an astronomer with Columbia University and the Flatiron Institute. "Today, it is nowhere to be seen, even with the most sensitive telescopes."
The Hubble Space Telescope displayed what the Universe looks like. Its successor, JWST, now reveals how the Universe grew up. Galaxies formed and grew massive swiftly: requiring under 300 million years. Larger-scale, more massive structures, like galaxy clusters, take longer. The earliest mature, fully-fledged cluster is CL J1001+0220. Simulations predict such clusters to appear late: after 2-3 billion years. However, proto-clusters, or still-forming galaxy clusters, appear far earlier.
One of the most exciting aspects is the rich chemistry we detect. We see dozens of different molecules, including some complex organic molecules that contain carbon, the same element that forms the basis of life on Earth. From ACES, we are learning more about how the ingredients for planets, and potentially life itself, can arise in the universe.
Each time we've looked at the Universe in a fundamentally new way, we didn't just see more of what we already knew what was out there. In addition, those novel capabilities allowed the Universe to surprise us, breaking records, revolutionizing our view of what was out there, and teaching us information that we never could have learned without collecting that key data.
an electron within a molecule gets excited to a higher-energy state, the electron de-transitions back to the lower energy state, where it emits light of a very specific wavelength in the process. Then, pumped or injected energy re-excites an electron within that very same molecule back into that higher-energy state, over and over.
This system is truly extraordinary. We're seeing the radio equivalent of a laser halfway across the universe. Fundamentally, masers and lasers are focused beams of light in the same frequency. In the realm of astrophysics, these can arise from clouds of dust being excited into a higher energy state from the light emitted by other sources, like stars and black holes.
