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We Finally Know How Black Holes Produce The Most Brilliant Light in The Universe

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An artist’s impression of astrophysical jets erupting from an active galactic nucleus. (ESO/M. Kornmesser)
For something that emits no light that we can detect, black holes just love to cloak themselves in radiance.

Some of the brightest light in the Universe comes from supermassive black holes, in fact. Well, not actually the black holes themselves; it’s the material around them as they actively slurp down vast amounts of matter from their immediate surroundings.

Among the brightest of these maelstroms of swirling hot material are galaxies known as blazars. Not only do they glow with the heat of a swirling coat, but they also channel material into ‘blazing’ beams that zoom through the cosmos, shedding electromagnetic radiation at energies that are hard to fathom.

Scientists have finally figured out the mechanism producing the incredible high-energy light that reaches us from billions of years ago: Shocks in the black hole’s jets that boost the speed of particles to mind-blowing velocities.

“This is a 40-year-old mystery that we’ve solved,” says astronomer Yannis Liodakis of the Finnish Centre for Astronomy with ESO (FINCA). “We finally had all of the pieces of the puzzle, and the picture they made was clear.”

Most of the galaxies in the Universe are built around a supermassive black hole. These mind-bogglingly large objects sit in the galactic center, sometimes doing very little (like Sagittarius A*, the black hole at the heart of the Milky Way) and sometimes doing a lot.

That activity consists of accreting material. A vast cloud assembles into an equatorial disk around the black hole, circling it like water around a drain. The frictional and gravitational interactions at play in the extreme space surrounding a black hole cause this material to heat up and shine brightly across a range of wavelengths. That’s one source of a black hole’s light.

The other – the one at play in blazars – are twin jets of material launched from the polar regions outside the black hole, perpendicular to the disk. These jets are thought to be material from the inner rim of the disk that, rather than falling toward the black hole, gets accelerated along external magnetic field lines to the poles, where it is launched at very high speeds, close to the speed of light.

For a galaxy to be classified as a blazar, these jets have to be almost directly pointed toward the viewer. That’s us, on Earth. Thanks to extreme particle acceleration, they blaze with light across the electromagnetic spectrum, including high-energy gamma- and X-rays.

Exactly how this jet accelerates the particles to such high speeds has been a giant cosmic question mark for decades. But now, a powerful new X-ray telescope called the Imaging X-ray Polarimetry Explorer (IXPE), launched in December 2021, gave scientists the key to solve the mystery. It’s the first space telescope that reveals the orientation, or polarization, of X-rays.

“The first X-ray polarization measurements of this class of sources allowed, for the first time, a direct comparison with the models developed from observing other frequencies of light, from radio to very high-energy gamma rays,” says astronomer Immacolata Donnarumma of the Italian Space Agency.

IXPE was turned to the brightest high-energy object in our sky, a blazar called Markarian 501, located 460 million light-years away in the constellation of Hercules. For a total of six days in March 2022, the telescope collected data on the X-ray light emitted by the blazar’s jet.

An illustration showing IXPE observing Markarian 501, with light losing energy as it moves farther from the shock front. (Pablo Garcia/NASA/MSFC)

At the same time, other observatories were measuring the light from other wavelength ranges, from radio to optical, which previously were the only data available for Markarian 501.

The team soon noticed a curious difference in the X-ray light. Its orientation was significantly more twisted, or polarized, than the lower-energy wavelengths. And the optical light was more polarized than the radio frequencies.

However, the direction of the polarization was the same for all wavelengths and aligned with the direction of the jet. This, the team found, is consistent with models in which shocks in the jets produce shockwaves that provide additional acceleration along the length of the jet. Closest to the shock, this acceleration is at its highest, producing X-radiation. Farther along the jet, the particles lose energy, producing lower-energy optical and then radio emission, with lower polarization.

“As the shock wave crosses the region, the magnetic field gets stronger, and energy of particles gets higher,” says astronomer Alan Marscher of Boston University. “The energy comes from the motion energy of the material making the shock wave.”

It’s not clear what creates the shocks, but one possible mechanism is faster material in the jet catching up to slower-moving clumps, resulting in collisions. Future research could help confirm this hypothesis.

Since blazars are among the most powerful particle accelerators in the Universe, and one of the best laboratories for understanding extreme physics, this research marks a pretty important piece of the puzzle.

Future research will continue to observe Markarian 501, and turn IXPE to other blazars to see if similar polarization can be detected.

The research has been published in Nature Astronomy.

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“Alien bases” may be hiding off the coast of Alaska, researchers say

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An organization of civilian volunteers dedicated to the study of
unidentified flying objects (UFOs) has issued a statement based on
decades of studying eyewitness reports. According to Mutual UFO Network,
“alien bases” may be hiding off the coast of Alaska, reports the-sun.com.

Researchers
say the deep waters in this region may hold something surprising. After
analyzing reports from the ship’s crew from 1945, they hypothesized
that alien objects could be lurking underwater, off the coast of the
state.

Alleged sightings of alien spacecraft nearly 80 years ago
have become a key point in research. Members of the organization believe
that UFOs move over water and may have “bases.”

Researchers
allege crew members on a U.S. Army transporter ship sailing past Island
Adak saw a massive UFO sized 150 to 200 feet emerge from the water.
Although these reports are nowhere to be found, UFO enthusiasts believe
the unidentified flying vehicles likely were used to commute to
different supposed alien bases hiding in the deep waters.

As
the “secret reports” of the sailors aren’t available, investigators
have taken it upon themselves to unravel the mystery surrounding the
unidentified flying objects and they believe the ocean has alien bases
that humans aren’t aware of.

Enthusiasts claim that UFOs may be
using “underwater networks” or wormholes as superhighways to travel
between points in the universe. UFO researcher Johnny Enoch added that
such objects could serve as a vehicle for aliens.

There are also
theories that other places on Earth could serve as bases for alien life.
A mountain in Seoul, South Korea is believed to be hiding a UFO,
according to Dr. Steven Greer.

An episode of the series “The
Alaska Triangle” features satellite imagery that claims to show one of
the “alien bases” in the Pacific Ocean off the coast of California.

Meanwhile,
another researcher featured in the program showed markings from the sea
bed that she claimed could have been roadways for aliens.

While
the mysteries of the ocean remain unsolved, researchers continue their
search, trying to unravel the mystery of what may be hiding in the
depths of the waters off the coast of Alaska.

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Enormous City-Size Comet Racing Towards Earth Grows ‘Devil Horns’ After Massive Eruption

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A volcanic comet the size of a mid-sized US city has
violently exploded for the second time in four months as it continues
racing toward the earth. And following the massive eruption, the cloud
of ice and gas sprouted what looked like a pair of gigantic devil horns.

The city-sized comet, named 12P/Pons-Brooks, is a cryovolcanic — or
cold volcano — comet. It has a solid nucleus, with an estimated diameter
of 18.6 miles, and is filled with a mix of ice, dust and gas known as
cryomagma. The nucleus is surrounded by a fuzzy cloud of gas called a
coma, which leaks out of the comet’s interior.

When solar radiation heats the comet’s insides, the pressure builds up
and the comet violently explodes, ejaculating its ice-cold innards into
space through seeping cracks in the nucleus’s shell.

Live Science report:
On Oct. 5, astronomers detected a large outburst from 12P, after the
comet became dozens of times brighter due to the extra light reflecting
from its expanded coma, according to the British Astronomical Association (BAA), which has been closely monitoring the comet 

Over the next few days, the comet’s coma expanded further and developed its “peculiar horns,” Spaceweather.com
reported. Some experts joked that the irregular shape of the coma also
makes the comet look like a science fiction spaceship, such as the
Millennium Falcon from Star Wars.

The unusual shape of the comet’s coma is likely due to an irregularity in the shape of 12P’s nucleus, Richard Miles, a BAA astronomer, told Live Science after the comet’s previous eruption.
The outflowing gas is likely being partially obstructed by a notch
sticking out on the nucleus, Miles said. As the gas continues to expand
away from the comet, the irregularity in the coma’s shape becomes more
defined and noticeable, he added.

12P is currently hurtling toward the inner solar system, where it
will be slingshotted around the sun on its highly elliptical 71-year
orbit around our home star — similar to the green comet Nishimura, which
pulled off a near-identical maneuver on Sept. 17

12P will reach its closest point to Earth on April 21, 2024, when it
may become visible to the naked eye before being catapulted back toward
the outer solar system. It will not return until 2095.

This is the second time 12P has sprouted its horns this year. On July
20, astronomers witnessed the comet blow its top for the first time in
69 years (mainly due to its outbursts being less frequent and harder to
spot during the rest of its orbit). On that occasion, 12P’s coma grew to
around 143,000 miles (230,000 km), which is around 7,000 times wider
than the comet’s nucleus.

It is unclear how large the coma grew during the most recent
eruption, but there are signs the outburst was “twice as intense” as the
previous one, the BAA noted. By now, the coma has likely shrunk back to
near its normal size.

As 12P continues to race toward the sun, there is a high probability
that we will witness several more major eruptions. It is possible that
those eruptions will be even bigger than the most recent one as the
comet soaks up more solar radiation, according to Spaceweather.com.

But 12P is not the only volcanic comet that astronomers are currently
monitoring: 29P/Schwassmann-Wachmann (29P) — the most volatile volcanic
comet in the solar system — has also had several noticeable eruptions
in the last year.

In December 2022, 29P experienced its largest eruption in around 12 years, which sprayed around 1 million tons of cryomagma into space. And in April this year, for the first time ever, scientists accurately predicted one of 29P’s eruptions before it actually happened, thanks to a slight increase in the comet’s brightness in the lead-up to the icy explosion.

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