Strange Skies
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Astronomers observe the first radiation belt seen outside of our solar system

Tim Stephens
University of California Santa Cruz
Mon, 15 May 2023 23:13 UTC

High-resolution imaging of radio emissions from an ultracool dwarf show a double-lobed structure like the radiation belts of Jupiter.

Astronomers have described the first radiation belt observed outside our solar system, using a coordinated array of 39 radio dishes from Hawaii to Germany to obtain high-resolution images. The images of persistent, intense radio emissions from an ultracool dwarf reveal the presence of a cloud of high-energy electrons trapped in the object's powerful magnetic field, forming a double-lobed structure analogous to radio images of Jupiter's radiation belts.

"We are actually imaging the magnetosphere of our target by observing the radio-emitting plasma — its radiation belt — in the magnetosphere. That has never been done before for something the size of a gas giant planet outside of our solar system," said Melodie Kao, a postdoctoral fellow at UC Santa Cruz and first author of a paper on the new findings published May 15 in Nature.

Strong magnetic fields form a "magnetic bubble" around a planet called a magnetosphere, which can trap and accelerate particles to near the speed of light. All the planets in our solar system that have such magnetic fields, including Earth, as well as Jupiter and the other giant planets, have radiation belts consisting of these high-energy charged particles trapped by the planet's magnetic field.

Mysterious, ultra low-frequency noises detected in Earth's atmosphere — and scientists can't explain them

Ben Turner
Live Science
Sat, 13 May 2023 11:35 UTC

Solar-powered balloons detected strange rumblings at a height of 70,000 feet above the Earth's surface. Scientists can't identify them.

Solar-powered balloons launched into the Earth's stratosphere have recorded a series of mysterious rumblings, and scientists can't pinpoint their origins.

The noises, detected by specialized instruments at 70,000 feet above the Earth's surface, are known as infrasound because they are so low-pitched they are inaudible to human ears. Picked out from among a wash of hidden low-frequency sounds — including thunder, ocean waves, rocket launches, cities, wind turbines and even planes, trains and automobiles — the strange infrasounds have so far defied explanation.

"[In the stratosphere,] there are mysterious infrasound signals that occur a few times per hour on some flights, but the source of these is completely unknown," lead investigator Daniel Bowman, a senior scientist at Sandia National Laboratories in New Mexico, said in a statement.

Beginning around 9 miles (14.5 km) above the Earth's surface and extending upwards to a height of roughly 31 miles (50 km), the stratosphere is the layer of atmosphere above our own. Filled with ultraviolet-blocking ozone, the stratosphere is a calm place, with little turbulence. The majority of sounds at this altitude originate from ultra low-frequency reverberations from the Earth's surface.

New discoveries double number of 'irregular' Saturn moons, bringing total count to 145

Jeff Hetch
Sky & Telescope
Fri, 12 May 2023 19:18 UTC

The Minor Planet Center is announcing a bevy of new moons for Saturn that will bring its total to 145 (and break Jupiter's record).

© K LyThis diagram shows the present-day orbits of the 41 new moons published so far, color-coded by the direction of their orbits (blue for prograde, in the direction of Saturn's rotation, and red for retrograde). The diagram is shown to scale; the size of the Earth's moon's orbit is shown for comparison at lower left.

Saturn has reclaimed the record for most moons in the solar system with the discovery of 62 new moons. All are only a few kilometers in size and have orbits far from the planet that indicate their origin: Saturn captured these rocks at some point in the past.

As of press time, the Minor Planet Center (MPC) has published the orbits of 41 new moons in a series of announcements, called Minor Planet Electronic Circulars, issued between May 3rd and 10th. Brett Gladman (University of British Columbia, Canada) said May 11th that the center would release orbits for an additional 21 moons shortly. That will bring Saturn's total moon count to 145, including 24 "regular" moons, which formed around the planet, and 121 smaller, "irregular" moons on wide, elongated, and tilted orbits. The new reports more than double Saturn's number of irregular moons, leaving Saturn far ahead of Jupiter's 95 moons, which had put Jupiter in first place earlier this year.

The torrent of Saturnian discoveries comes from a series of observations that Edward Ashton (now at Academia Sinica Institute of Astronomy and Astrophysics, Taiwan) and colleagues, including Gladman, made with the Canada France Hawaii Telescope from 2019 to 2021. Their initial goal was to study the sizes of moons orbiting Saturn, and in 2021 they reported the size distribution of the small irregular moons. The larger amount of smaller moons indicates a recent (100 million years ago) collision between two objects around Saturn. To record faint moons down to a couple kilometers in size, the group stacked series of images, a method used previously to search for moons around Uranus and Neptune, but not previously for Saturn.

Most powerful cosmic explosion spotted by astronomers

Ben Turner
Live Science
Thu, 11 May 2023 23:59 UTC

Astronomers have spotted a giant explosion releasing over 100 times more energy than the sun will release across its entire lifetime. A monster black hole is likely to blame.

Astronomers have spotted the most powerful cosmic explosion ever seen — a mysterious, years-long eruption 10 times brighter than any observed supernova.

Astronomers spotted the event, named AT2021lwx, 8 billion light-years from Earth. Releasing roughly 100 times the energy the sun will release over its entire lifetime, the strange explosion burst into activity when the universe was 6 billion years old.

"We came upon this by chance, as it was flagged by our search algorithm when we were searching for a type of supernova," study lead author Philip Wiseman, an astronomer at the University of Southampton in the U.K., said in a statement. "Most supernovae and tidal disruption events [bright flashes that occur when black holes tear apart wandering stars] only last for a couple of months before fading away. For something to be bright for two plus years was immediately very unusual."

The cause of the mysterious explosion is unclear, but astronomers think it's most likely the result of a gigantic cloud of hydrogen gas thousands of times larger than our sun being gobbled up by a supermassive black hole.

Ex-Russian space boss questions US Moon landing

RT.com
Sun, 07 May 2023 19:01 UTC

Dmitry Rogozin says that while many in Roscosmos defended Washington's version of events, no one could produce irrefutable proof.

The former head of Russia's Roscosmos space agency, Dmitry Rogozin, has expressed doubt that the US Apollo 11 mission really landed on the Moon in 1969, saying he has yet to see conclusive proof.

In a post on his Telegram channel on Sunday, Rogozin said he began his personal quest for the truth "about ten years ago" when he was still working in the Russian government, and that he grew skeptical about whether the Americans had actually set foot on the Moon when he compared how exhausted Soviet cosmonauts looked upon returning from their flights, and how seemingly unaffected the Apollo 11 crew was by contrast.

Rogozin said he sent requests for evidence to Roscosmos at the time. All he received in response was a book featuring Soviet Cosmonaut Aleksey Leonov's account of how he talked to the American astronauts and how they told him they had been on the Moon.

NASA's enigmatic green lasers spotted by Japanese astronomer

Isaac Schultz
Gizmodo
Mon, 17 Apr 2023 23:58 UTC

Japanese museum curator and astronomer Daichi Fujii spotted something irregular last September in several motion-sensing cameras he had set up: three brilliant green lights that streaked across the sky.

After studying the footage and comparing it to orbital data, Fujii found the responsible party: NASA's Ice, Cloud and Land Elevation Satellite 2, or ICESat-2, which had flown over Japan that night.

According to Tony Martino, an instrument scientist for the satellite, it's the first time the team has seen footage of the instrument's lasers pulsing through the sky.

"ICESat-2 appeared to be almost directly overhead of [Fujii], with the beam hitting the low clouds at an angle," Martino said in a NASA release. "To see the laser, you have to be in the exact right place, at the right time, and you have to have the right conditions."

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ICESat-2 launched in 2018 and is used to measure the height of Earth's surfaces. It is basically a space-based lidar scanner, similar to those used by archaeologists to discover ancient sites lost to natural features like forest growth.

The video footage was captured on September 16, 2022. It shows three streaks of light zip across the sky against a backdrop of scattered clouds. Upon further scrutiny, Fujii realized the green streaks pulsed in time with a light that briefly appeared between the clouds (just above the center of the video frame, if you want to spot it yourself).

NASA confirms first radar-observed meteor fall seen in Maine

Camille Fine
USA Today
Wed, 12 Apr 2023 21:27 UTC

A fireball that caused loud sonic booms and even lit up the daytime sky on Saturday was the first radar-observed meteorite fall seen in Maine, NASA confirmed.

"Booming" noises were heard near Calais, Maine, shortly after the fireball was seen moving through the sky. This apparent meteorite fall occurred at 11:56 a.m. local time, NASA said.

NASA's radar was able to observe the event for nearly five minutes and calculated fallen meteorite masses from 1.59 — 322 grams, or less than a pound, "although larger masses may have fallen."

Because of this, the Maine Mineral & Gem Museum in Bethel is offering a $25,000 reward for the first meteorite they get weighing one kilogram or more, the Bangor Daily News reported.

Rare ELVE photographed during intense lightning storm over Italy

Space Weather
Mon, 27 Mar 2023 12:00 UTC

Elves
Taken by Valter Binotto on March 27, 2023 @ possagno, TV Italy

For a few milliseconds last Monday night, March 27th, an enormous red ring of light appeared in the sky over central Italy. Valter Binotto photographed it from the small town of Possagno in the foothills of the Italian Alps:

This is an "ELVE"--short for Emissions of Light and Very Low Frequency Perturbations due to Electromagnetic Pulse Sources. It's a rare species of sprite discovered in 1990 by cameras onboard the space shuttle. Binotto may have just taken the best ever picture of one from the ground.

"The ELVE was generated by intense lightning in a storm near Ancona about 285 km south of me," says Binotto. One bolt was so strong, it generated an intense electromagnetic pulse (EMP). The red ring marks the spot where the EMP hit Earth's ionosphere. Normal lightning bolts carry 10 to 30 kilo-ampères of current; this bolt was about 10 times stronger than normal.

Comment: See also:

And check out SOTT radio's:

Brightest gamma-ray burst ever detected defies explanation

Stephanie Pappas
Live Science
Tue, 28 Mar 2023 19:02 UTC

Scientists are taking a closer look at the afterglow left by the brightest gamma-ray burst ever recorded, and what they see doesn't fit with any theoretical models.

The brightest gamma-ray burst ever detected is revealing new mysteries as scientists study it in greater detail.

In two new papers - one published today in The Astrophysical Journal Letters, and another published on the preprint server arXiv and submitted for publication in the journal Nature Astronomy - astronomers found that the evolution of the radio waves released by an enormous stellar explosion seen in 2022 was slower than models predicted, raising questions about how the release of energy evolves during ultra-powerful gamma-ray bursts.

"[I]t is very difficult for existing models to replicate the slow evolution of the energy peaks that we observed," James Leung, a doctoral student at the University of Sydney who co-authored the Nature Astronomy paper, said in a statement. "This means we have to refine and develop new theoretical models to understand these most extreme explosions in the Universe."

Gamma-ray bursts (GRBs) are brief, bright flashes of gamma-ray light that are thought to be the most powerful explosions in our universe since the Big Bang. GRBs are released during extreme stellar explosions or supernovas, when a dying star runs out of fuel and collapses into a neutron star or even a black hole. The brightest burst ever seen, known as GRB 221009A, was first detected on Oct. 9, 2022 by gamma-ray and X-ray telescopes. The likely supernova that caused the burst was 2.4 billion light-years away from Earth.

Massive Aurora Australis solar storm seen over Tasmania, Australia and New Zealand

CLEARSKIESTV
YouTube
Sat, 25 Mar 2023 14:03 UTC

Naked eye aurora australis visible from Franklin, Tasmania on the night of 23/3/2023. All the colours visible in this footage were visible to the naked eye, which is extremely rare for Aurora.

This is easily the biggest and brightest aurora display I've seen in the 23 years I have been chasing aurora. It doesn't get much better than this from Australia.

Aurora gets such a bad wrap for being colourless, but once it got bright enough the colour receptors in my eyes suddenly switched on.

It was like upgrading from a B&W TV to full HD.