#doppler-shift

#doppler-shift

This system is truly extraordinary. We are seeing the radio equivalent of a laser halfway across the universe. This galaxy acts as a lens, the way a water droplet on a window pane would, because its mass curves the local space-time. So we have a radio laser passing through a cosmic telescope before being detected by the powerful MeerKAT radio telescope.

Stellar activity such as solar storms and plasma turbulence from a star near a transmitting planet can broaden otherwise ultra-narrow signals. That spreads the power of any such transmission across more frequencies, the institute's scientists say, which makes it more difficult to detect using traditional narrowband searches.

Light is one aspect of the Universe that, for most people, holds a deep and noticeable value in everyday life, helping them to navigate, learn from, and connect with the world around them. Yet it's not particularly difficult to imagine life without it. After all, many nonhuman animals live in lightless environments. However, as Gideon Koekoek, an associate professor of physics in the research group Gravitational Waves and Fundamental Physics

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.

The first time that University of Oxford astronomer Lyla Jung saw the cosmic configuration on her monitor, she almost didn't believe it was real. But it wasand Jung and her colleagues went on to identify one of the largest rotating structures ever found in space: a chain of galaxies embedded in a spinning cosmic filament 400 million light-years from Earth. The finding, published in Monthly Notices of the Royal Astronomical Society, may give astronomers new insights into galaxies' formation, evolution and diversity, Jung says.

The universe is exploding. Or parts of it are. The night sky may seem calm, even serene, but that masks events of a catastrophic and nearly unimaginable scale. Across the galaxy and even the cosmos itself, immense outbursts of energy occur that could easily vaporize our planet. Happily, space is vast, and the terrible distance between these events and us diminishes what we see to a faint glowusually.

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.

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.

The sun is putting on a show. On Sunday the star unleashed several strong and bright solar flares, including one of the most powerful eruptions seen in decades. Far from the steadily glowing orb we sometimes picture, the sun's surface is made up of roiling plasma thrown about by twisting magnetic fields. When these fields snap, they can throw out huge bursts of energy and charged particles into spacea solar flare.

A dead star 730 light years away appears to be forming a powerful structure around itself - and despite their best efforts, astronomers aren't sure how. The cosmic corpse, designated RXJ0528+2838, is an incredibly dense stellar remnant known as a white dwarf, with a Sun-like star orbiting around it. This binary arrangement isn't uncommon throughout the universe, but what is strange is the structure surrounding the former body: a highly energetic and luminescent cloud known as a nebula,