#cosmic-jets

#cosmic-jets

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.

The generation of coherent extreme ultraviolet and X-ray photons by high harmonic generation from solid targets relies on the formation of a steep electron density gradient tuned by the leading edge of a relativistically intense laser pulse interacting with a bulk, solid-density target.

The precise expansion rate of the universe - called the Hubble constant - has turned into a major pain point as attempts to nail it down keep leading to widely differing figures.

The atmosphere of TOI 5205b has a lower concentration of heavy elements relative to hydrogen than gas giants in our own solar system, suggesting something different about its formation.

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."

Looking skyward fills us with wonder. Off-world, the Sun, planets, stars, and galaxies all await. Our Solar System encompasses our own cosmic backyard. Farther away, stars and star clusters abound within the Milky Way. Hundreds of billions of stars exist just within our home galaxy. Inside our Local Group, only Andromeda surpasses us in mass, size, and stars. More than 5 million light-years away, galaxies abound in groups and clusters.

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.

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.

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.