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It’s a slippery number, however. Measurements using different techniques have produced different results, and the numbers show no sign of converging even as researchers refine their observations

the theorists are intrigued. They hope the Hubble Constant confusion is the harbinger of a potential major discovery — some "new physics."

“Any time there’s a discrepancy, some kind of anomaly, we all get very excited,”

“Where’s it all going to go? How’s it all going to end? That’s a big question,”

One idea floating around is that there could have been something called Early Dark Energy that skewed the appearance of the background radiation

“New physics might be that there’s some form of energy that acted in the earliest moments of the evolution of the universe. You’d get an injection of energy that’d then have to disappear,”

Leavitt, a then-obscure employee of the Harvard College Observatory, discovered that the intrinsically brighter stars have longer periods. This insight — Leavitt’s law — allows astronomers to know the Cepheid’s absolute luminosity, then gauge the distance to the star based on how bright or faint it appears.

just to be clear: The Hubble Constant in question is the rate of expansion in our “local” universe, not the rate of expansion when the background radiation was first emitted billions of years ago. Over time, the Hubble Constant isn’t constant.)

At the dawn of the 21st century, this Standard Model seemed to pass every observational test. And any disparities in the measurement of the Hubble Constant would surely be ironed out with further observations, scientists assumed. They had even nailed down the age of the universe precisely: 13.8 billion years.

“We felt really good,”

He added, jokingly, “We should have stopped taking data.”

“We are wired to use our intuition to understand things around us,” Riess said. “Most of the universe is made out of stuff that’s completely different than us. This adherence to intuition is often wildly unsuccessful in the universe.”

"These small year-to-year changes in Saturn's color bands are fascinating," said Amy Simon, planetary scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland, in a statement.

From 2018 to 2020, Saturn's equator brightened between 5% and 10%, while winds near the equator actually slowed from 1,000 miles per hour to about 800 miles per hour.

“They speed up and slow down, rock their north pole towards the planet and back again and maybe even reverse direction,” said Hamilton. “It would be a pretty confusing system to be in.”

The findings, published in the journal Nature, were based on ten years of observations of Pluto from the Hubble space telescope, which the researchers re-analysed after the relatively recent discovery of the four small moons

Unaccounted for, this missing matter was predicted to exist, but hard to find. In fact, astronomers have been searching for it over the last 30 years, the researchers said. Measurements of the Big Bang show how much matter was present in the early days of the universe, suggesting its existence.

"It turned out that it was hiding in a density so low that it does not emit light, it doesn't absorb it, and it doesn't reflect it," he said.

"The radiation from fast radio bursts gets spread out by the missing matter in the same way that you see the colors of sunlight being separated in a prism," Macquart said.

"Their millisecond durations made it very easy to measure the effect of dispersion — the process by which their longer wavelength emission is delayed with respect to their shorter wavelength emission is delayed — and hence to measure exactly how much matter they have encountered on their multi-billion year intergalactic journeys to Earth," Macquart said.

Astronomers were able to pin down the source of a repeating fast radio burst in 2017. But single radio bursts are harder to pinpoint because they don't reoccur.

"ASKAP both has a wide field of view, about 60 times the size of the full Moon, and can image in high resolution," said Ryan Shannon, study coauthor and associate professor at Swinburne University of Technology, in a statement. "This means that we can catch the bursts with relative ease and then pinpoint locations to their host galaxies with incredible precision.

"We've discovered the equivalent of the Hubble-Lemaître Law for galaxies, only for fast radio bursts," Macquart said. "The Hubble-Lemaître Law, which says the more distant a galaxy from us, the faster it is moving away from us, underpins all measurements of galaxies at cosmological distances."