Strange Skies
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Discovery of massive early galaxies defies prior understanding of the universe

Adrienne Berard
The Pennsylvania State University
Wed, 22 Feb 2023 17:58 UTC
6 massive galaxies,
© NASA, ESA, CSA, I. Labbe (Swinburne University of Technology). Image processing: G. Brammer (Niels Bohr Institute’s Cosmic Dawn Center at the University of Copenhagen). All Rights Reserved.Images of six candidate massive galaxies, seen 500-700 million years after the Big Bang. One of the sources (bottom left) could contain as many stars as our present-day Milky Way, according to researchers, but it is 30 times more compact.
UNIVERSITY PARK, Pa. — Six massive galaxies discovered in the early universe are upending what scientists previously understood about the origins of galaxies in the universe.

"These objects are way more massive​ than anyone expected," said Joel Leja, assistant professor of astronomy and astrophysics at Penn State, who modeled light from these galaxies. "We expected only to find tiny, young, baby galaxies at this point in time, but we've discovered galaxies as mature as our own in what was previously understood to be the dawn of the universe."

Using the first dataset released from NASA's James Webb Space Telescope, the international team of scientists discovered objects as mature as the Milky Way when the universe was only 3% of its current age, about 500-700 million years after the Big Bang. The telescope is equipped with infrared-sensing instruments capable of detecting light that was emitted by the most ancient stars and galaxies. Essentially, the telescope allows scientists to see back in time roughly 13.5 billion years, near the beginning of the universe as we know it, Leja explained.

"This is our first glimpse back this far, so it's important that we keep an open mind about what we are seeing," Leja said. "While the data indicates they are likely galaxies, I think there is a real possibility that a few of these objects turn out to be obscured supermassive black holes. Regardless, the amount of mass we discovered means that the known mass in stars at this period of our universe is up to 100 times greater than we had previously thought. Even if we cut the sample in half, this is still an astounding change."
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Astronomers 'discover' a dozen more new moons around Jupiter

Jeff Hecht
Sky & Telescope
Tue, 31 Jan 2023 18:45 UTC
The discovery of a dozen new moons for Jupiter makes the king of planets the king of moons, too — at least for now.

The biggest planet in the solar system now has the largest family of moons. Since December 20th, the Minor Planet Center (MPC) has published orbits for 12 previously unreported moons of Jupiter. More publications are expected, says Scott Sheppard (Carnegie Institute for Science), who recently submitted observations of the Jovian system taken between 2021 and 2022. The discoveries bring the list of Jovian moons to 92, a hefty 15% increase from the previous tally of 80.

The MPC's orbital calculations confirm the new objects are in orbit around Jupiter. Other data from Sheppard's observations even enabled recovery of the last "missing" Jovian moon, S/2003 J 10; the newest observations extended the track of its orbit to 18 years.
Jupiters New Moons
© Scott SheppardThis top-down diagram shows the orbits of moons around Jupiter: Purple denotes the Galilean moons, yellow for Themisto, blue for the Himalia group, cyan and green for Carpo and Valetudo, respectively, and red for far-out retrograde moons. (Note: The number of moons in this diagram is not up to date.)

Comment: 'Discovered' as in 'somehow we missed them before', or 'discovered' as in they are newly acquired by Jupiter from a comet swarm coming into the solar system?

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Ultra-rare 'rainbow clouds' light up the Arctic Circle like auroras in stunning new photos

Harry Baker
Live Science
Tue, 31 Jan 2023 16:38 UTC
Rare clouds that give off bright, multi-colored light like an aurora were recently spotted at multiple locations in the Arctic. But what causes them?
Rare Clouds
© Jónína Guðrún ÓskarsdóttirBright multi-colored clouds shining in the night sky above Mount Jökultindur in Iceland on Jan. 25.
The dark skies in the Arctic Circle recently shone with ethereal multi-colored light. But this jaw-dropping spectacle was not caused by auroras. Instead, the iridescent rainbows were caused by clouds of tiny ice crystals floating higher in the atmosphere than is normally possible.

The clouds, known as polar stratospheric clouds (PSC), only form when the lower stratosphere reaches temperatures below minus 114 degrees Fahrenheit (minus 81 degrees Celsius). Normally, clouds do not form in the stratosphere because it is too dry, but at these extremely low temperatures "widely-spaced water molecules begin to coalesce into tiny ice crystals" that form into clouds, Spaceweather.com reported. This means PSCs can form much higher up than normal clouds, between 9.3 and 15.5 miles (15 to 25 kilometers) above the ground.

As sunlight shines through these crystal clouds, it gets scattered, creating multiple different wavelengths of light, which has inspired the PSCs nickname, "rainbow clouds." Due to the extreme altitude of the clouds sunlight can hit the crystals and scatter above an observer even if the sun is beyond the horizon, which is when these clouds appear brightest.
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Telescope

Rare outbreak of polar stratospheric clouds photographed in Iceland, NASA confirms sightings occurred alongside sudden temperature drop


Space Weather
Wed, 25 Jan 2023 21:45 UTC
polar stratospheric clouds
© Taken by Richard Jenkinson on January 24, 2023 @ Nellim North Finland.These were taken by a friend using an Iphone 12. His name is Francois Guilhaume-Bohl. He took these photos this morning in Nellim Finland whilst out walking. I have submitted these photos with his permission on his behalf. This show continued for a long time this morning. I said as it was such an outstanding show he should submit these to Spaceweather, and he asked me to so.
Arctic skies are filling with color today--but it's not the aurora borealis. A rare outbreak of polar stratospheric clouds (PSCs) is underway. Jónína Óskarsdóttir photographed the display from Fáskrúðsfjörður, Iceland:
polar stratospheric clouds
There have been beautiful nacreous clouds for couple of days. This photo was taken in Fáskrúðsfjörður, Iceland today. Mt. Jökultindur in front and the sky behind covered in colourful nacreous clouds.
"We have been seeing these clouds for a couple of days," reports Óskarsdóttir. "In this picture, Mt. Jökultindur is silhouetted by a sky-full of nacreous color."

Comment: See also:

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Comet

'Sun breaks tail of comet': Disconnection event observed on Comet ZTF


Space Weather
Wed, 18 Jan 2023 23:32 UTC
Something unusual is happening to the tail of Comet ZTF (C/2022 E3). It's being disconnected. The break is inset in this picture taken by Austrian astrophotographer Michael Jaeger on Jan. 17th:
comet ztf
This is a disconnection event: A piece of Comet ZTF's tail has been pinched off and is being carried away by the solar wind.

Blame space weather. CMEs hitting comets can cause magnetic reconnection in comet tails, sometimes ripping them off entirely. NASA's STEREO-A spacecraft watched this happen to Comet Encke in April 2007: movie.

This month, multiple CMEs have swept past Comet ZTF as a result of surging solar activity. One of them is responsible for the disconnection event.

Soon, we'll get a better look. Comet ZTF is approaching Earth for a close encounter (0.28 AU) on Feb. 1st. Between now and then, the comet's brightness will cross the threshold of naked-eye visibility, possibly peaking at magnitude +5. CME effects will be increasingly visible as the comet approaches. Stay tuned!

Comment: See also:

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Amateur astronomers find glowing gas arc near Andromeda

Govert Schilling
Sky & Telescope
Tue, 17 Jan 2023 17:48 UTC
Andromeda Galaxy
© Yann Sainty and Marcel DreschselA composite image including filters for hydrogen-alpha (red) and doubly ionized oxygen (green) reveals a large arc near Andromeda Galaxy on the sky.
French and German amateur astronomers have discovered a mysterious nebulous arc close to the Andromeda galaxy (M31), and no one has a clue about its true nature. The arc, detected in the light of doubly ionized oxygen, has never been seen before, and doesn't seem to radiate at any other wavelength. "The [Andromeda] galaxy has kept one secret for a very long time," the team comments in a YouTube video about the discovery.

Using sophisticated amateur equipment, Xavier Strottner and Marcel Drechsler have already found dozens of previously unknown planetary nebulae in our galaxy. Last fall, analyzing images obtained by Yann Sainty, they stumbled upon a much larger structure, just 1.2 degrees southeast of Andromeda's nucleus. The arc extends over 1.5 degrees and ends close to the naked-eye star Nu (ν) Andromedae (the blue star at the top of the photo).

Sainty used a 4.2-inch Takahashi refractor and a large-format ZWO CMOS camera outfitted with a narrow-band filter that only transmits the greenish, 500.7-nanometer light emitted by oxygen atoms that have lost their outermost two electrons (the [OIII] line). His wide-angle images added up to a total exposure time of more than 100 hours. Subsequent images, made with five different setups in France and the United States, have confirmed the existence of the [OIII] arc, which is now known as Strottner-Drechsler-Sainty Object 1 (SDSO-1).

Because of the arc's huge angular size and its extremely low surface brightness, professional surveys hadn't previously detected it. A brief paper describing the discovery, written by the three amateur astronomers together with professional researchers, has appeared in Research Notes of the AAS.
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850-year-old supernova left 'zombie star' behind

Govert Schilling
Sky & Telescope
Sat, 14 Jan 2023 04:12 UTC
Nebula PA 30
© Robert FesenThe unusual fireworks-like structure of nebula Pa 30 may result from the merger of two dying stars.
A supernova explosion that skywatchers in the Far East observed almost 850 years ago has produced the most unusual remnant astronomers have ever found. "I've worked on supernovae for [decades], and I've never seen anything like this," says Robert Fesen (Dartmouth College), who photographed the weird object in late October 2022 with the 2.4-meter Hiltner telescope at Kitt Peak.

Fesen presented his results at the 241st meeting of the American Astronomical Society (AAS) in Seattle; a paper has been submitted to Astrophysical Journal Letters (preprint available here). In other work presented at the AAS meeting and submitted to Monthly Notices of the Royal Astronomical Society (preprint here), his coauthor Bradley Schaefer (Louisiana State University) argues that the supernova resulted when two white dwarf stars collided, leaving an extremely energetic "zombie" star behind.

Amateur astronomer (and Fesen's second coauthor) Dana Patchick discovered the nebula in August 2013 in archived images from NASA's Widefield Infrared Survey Explorer (WISE). The infrared images didn't show much detail, though. Originally, Patchick believed he had found a planetary nebula — his 30th find, hence the name Pa 30 — but later spectroscopic observations revealed that it's more likely to be a supernova remnant. However, the nebula doesn't produce many radio or X-ray waves, and there's no neutron star or black hole in its center. Instead, the central star (sometimes known as Parker's Star, after University of Hong Kong astronomer Quentin Parker who first studied its spectrum) turns out to be a peculiar white dwarf.

Still, astronomers are now confident about its relation with SN1181, a zero-magnitude supernova that appeared in northern Cassiopeia on August 6th of 1181 AD. Chinese and Japanese observers recorded this "guest star" slowly fading over a period of six months.
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Grey Alien

'We have nothing' showing UFOs are of alien origin, says US Defense official

Kirsten Errick
NextGov
Thu, 05 Jan 2023 19:17 UTC
So far, data has not shown unidentified anomalous phenomena to be from an alien source, according to defense officials.
UAPs / UFOs
© DAVID WALL/GETTY IMAGES
Unlike what is portrayed in television and movies, the government has not found evidence of UFOs — or unidentified flying objects — that are extraterrestrial in nature. However, the government is expanding efforts to collect data on objects it still can't explain.

According to a media roundtable held last month, the Defense Department's All-domain Anomaly Resolution Office is tracking and analyzing unidentified anomalous phenomena, or UAP — the term is an updated version of UFO and the previous version of UAP, or unidentified aerial phenomena, to reflect unidentified phenomena not just in the air, but also on the ground and in sea and space — that pose a threat.

"Unidentified objects in the skies, sea and space pose potential threats to safety and security, particularly for operational personnel," AARO Director Sean Kirkpatrick said. "AARO is leading a focused effort to better characterize, understand and attribute these objects and is employing the highest scientific and analytic standards."

As noted at the roundtable, AARO — which was provided for in the 2022 National Defense Authorization Act, established in July and replaced the former Navy-led Unidentified Aerial Phenomena Task Force — is working with other agencies to improve its data collection on UAPs. Agency partners include military services, the intelligence community, the Energy Department, NASA, the Federal Aviation Administration, the National Oceanic and Atmospheric Administration and others.
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Info

Ancient Chinese text reveals earliest-known record of a candidate aurora

Jennifer Ouellette
Ars Technica
Sun, 01 Jan 2023 13:09 UTC
Passage in Bamboo Annals describes a "five-colored light" in 10th century BCE.

Auroral display over snow-capped mountains in Hangzhou, China.
© Liu Míng Sun/EyeEm/Getty ImagesAuroral display over snow-capped mountains in Hangzhou, China.
There's rarely time to write about every cool science-y story that comes our way. So this year, we're once again running a special Twelve Days of Christmas series of posts, highlighting one science story that fell through the cracks in 2022, each day from December 25 through January 5. Today: New analysis of an ancient Chinese text revealed the earliest candidate aurora yet found, predating the next oldest by three centuries.
A pair of researchers has identified the earliest description, in an ancient Chinese text, of a candidate aurora yet found, according to an April paper published in the journal Advances in Space Research. The authors peg the likely date of the event to either 977 or 957 BCE. The next-earliest description of a candidate aurora is found on Assyrian cuneiform tablets dated between 679-655 BCE, three centuries later.

As we've reported previously, the spectacular kaleidoscopic effects of the so-called northern lights (or southern lights if they are in the Southern Hemisphere) are the result of charged particles from the Sun being dumped into the Earth's magnetosphere, where they collide with oxygen and nitrogen molecules — an interaction that excites those molecules and makes them glow. Auroras typically present as shimmering ribbons in the sky, with green, purple, blue, and yellow hues.

There are different kinds of auroral displays, such as "diffuse" auroras (a faint glow near the horizon), rarer "picket fence" and "dune" displays, and "discrete aurora arcs" — the most intense variety, which appear in the sky as shimmering, undulating curtains of light. Discrete aurora arcs can be so bright, it's possible to read a newspaper by their light. That was the case in August and September 1859, when there was a major geomagnetic storm — aka, the Carrington Event, the largest ever recorded — that produced dazzling auroras visible throughout the US, Europe, Japan, and Australia.
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Cloud Lightning

2022: Storms, Sheets of Rain and Tornadoes in the Netherlands

Amari Roos
Sott.net
Thu, 29 Dec 2022 20:23 UTC
storm corrie scheveningen
© indebuurtStorm Corrie touches down in Scheveningen, a district of The Hague, Netherlands, on January 31st, 2022.
There was a stormy start to 2022 as at least four storms battered the Netherlands throughout the end of January and February. During the year, the country also saw snowfall, floods, sinkholes, tornadoes and fireballs. Below are some highlights from extreme weather events in the Netherlands in 2022.

Comment: See also:

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