#cosmic-objects

#cosmic-objects

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 worst place to live on Earth is actually the safest place to live on another planet," he adds.

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.

Okay, first thing first: the universe is in fact expanding. We've known this for more than a century now, and it's the basis for modern cosmology. This idea is called the big bang modelwhich is an unfortunate name because it brings to mind a cosmos expanding like an explosion, with galaxies moving away from each other through space like shrapnel. But in fact space itself is expanding, and that's different.

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 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.

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 solar system's most giant planet is slightly less of a giant than scientists once thought. Jupiter, a world that is so huge that it could hold 1,000 Earths, is eight kilometers narrower in width at its equator and 24 kilometers flatter at its poles than had been previously estimated, according to a new study. Textbooks will need to be updated, said Yohai Kaspi, a professor at the Weizmann Institute of Science in Rehovot, Israel, and senior author of the study, in a statement.