Comets


Comet 2

Volcanic 'devil comet' racing toward Earth resprouts its horns after erupting again

Harry Baker
Live Science
Tue, 07 Nov 2023 17:16 UTC
The massive volcanic comet 12P/Pons-Brooks, which grows giant horns when it erupts, has exploded for a third time in five months as it continues to race toward the sun.
12P/Pons-Brooks
© Comet Chasers/Richard MilesThe "devil" comet's distinctive horns were first spotted after a major eruption on July 20.
A volcanic "devil comet" that is racing toward Earth erupted again on Halloween, causing it to regrow its distinctive "horns." The latest outburst, which was the second within a month and the third since July, is a reminder that the comet is becoming more volcanically active as it continues its journey toward the heart of the solar system.

The comet, named 12P/Pons-Brooks (12P), is a cryovolcanic, or cold volcano, comet. Like other comets, 12P has a solid nucleus — a hard, icy shell filled with ice, gas and dust — that is surrounded by a fuzzy cloud, or coma made of materials that leak out of the comet's insides.

But unlike non-volcanic comets, radiation from the sun can superheat 12P's interior, causing pressure to build up until it becomes so intense it cracks the nucleus' shell from the inside and sprays its icy guts into space. These eruptions cause the comet's coma to expand and brighten as it reflects more sunlight toward Earth.

When the comet erupts, its coma forms iconic devil "horns." These occur because 12P's large nucleus, which spans around 10.5 miles (17 kilometers) across, has an unusual "notch" on its surface, which blocks the outflow of cryomagma into space and causes its expanded coma to grow with an irregular shape.
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Crusader

SOTT Focus: Witches, Comets and Planetary Cataclysms

Laura Knight-Jadczyk
Sott.net
Sat, 30 Oct 2010 16:59 UTC
witch1
© Dot Connector Magazine
When you think of Halloween, what is the first image that comes to mind? I took a little informal poll among my friends, family and associates. Guess what image came in first? Jack-o-lanterns! Bet you thought I was going to say "witches". Well, I sure thought it would be witches, but they only came in a close second!..

When I think of Halloween, I think of grade-school art projects where we cut out silhouettes of witches to paste onto large yellow moons made of construction paper. The witch was always on a broom with her black dress flying in the wind, accompanied by a black cat sitting on the back of the broom. I wondered even then how the cat managed to stay on and why anybody would think that straddling a broomstick as a seat would be even remotely comfortable.
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Info

Shock fractures in quartz and the Younger Dryas impact at Abu Hureyra (near Gobekli Tepe)

Dr.Martin Sweatman
PreHistory Decoded
Tue, 03 Oct 2023 16:51 UTC
Impact Event
© Prehistory Decoded
Researchers associated with the comet research group have just published four new papers on micro-fractures in quartz, and how they can be used to diagnose cosmic impacts. The first paper is a detailed study linking shocked quartz to airbursts. The next three below apply this new understanding to the Younger Dryas impact specifically at Abu Hureyra, which is about 100 miles south of Gobekli Tepe.

The journal is also new - "Airbursts and cratering impacts". It was set up so that papers rejected by the "impact mafia" can still be fairly reviewed and published. The impact mafia is a determined group of researchers who are expert in the more well-established science of large ground impacts where the existence of a large crater makes the diagnosis of an impact obvious. By requiring the same kind of evidence for the diagnosis of all cosmic impacts, they are effectively preventing the diagnosis of lower-energy impact events, for example small ground impacts or large airbursts that significantly affect the ground, i.e. precisely the kind of impacts central to the Younger Dryas impact hypothesis. Inevitably, this leads to under-reporting of these smaller impact events. Parallels with the "Clovis first mafia" are apt.
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Arrow Up

NASA predicts large asteroid impact could be in Earth's future

Bill Shannon
KTLA
Wed, 20 Sep 2023 07:13 UTC
Asteroid Bennu
© NASA/Goddard/University of Arizona/CSA/York/MDA via APThis undated image made available by NASA shows the asteroid Bennu from the OSIRIS-REx spacecraft. On Wednesday, Aug. 11, 2021, scientists said they have a better handle on asteroid Bennu’s whereabouts for the next 200 years. The bad news is that the space rock has a slightly greater chance of clobbering Earth than previously thought. But don’t be alarmed: Scientists reported that the odds are still quite low that Bennu will hit us in the next century.
NASA scientists are predicting a chance that asteroid Bennu will strike Earth in the future, potentially affecting an area the size of Texas.

Bennu is a Near-Earth Object (NEO) that passes by the planet roughly every six years, and experts have been watching it since it was discovered in September 1999.

According to scientists, Bennu has a chance to pass through what they call a "gravity keyhole," which would send it on a collision course with Earth in the year 2182.

A new paper from the OSIRIS-REx science team predicts Bennu has a 0.037% chance (1 in 2,700) of hitting Earth; this will largely depend on another flyby. In 2135, Bennu will zoom past Earth just close enough that our planet's gravitational pull could affect it in just the right way to put it on a path to hit us on Sept. 24, 2182 — almost 159 years to the day from this writing.
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Fireball 5

'Lightning' on Venus is actually meteors burning up in planet's atmosphere, study says

Sharmila Kuthunur
Space.com
Thu, 14 Sep 2023 19:01 UTC
But future missions, scientists say, are safe from both rare lightning strikes and meteors known to burn up high above the planet's clouds.
Venus
© FutureVenus as clicked by the Akatsuki orbiter in March 2018.
The thick, acid-rich clouds of Venus continue to shroud the planet next door in mystery.

Scientists have long-debated whether intriguing light flashes recorded by previous Venus missions are evidence of lightning strikes on the planet. If those flashes really represent lightning, future missions to the windy planet need to be designed such that they are strong enough to survive the bolts, which are known to damage electronics here on Earth.

Moreover, lightning on Venus means Earth's cosmic neighbor would join the rare planetary club whose current members — Earth, Jupiter and Saturn — host lightning bolts in their clouds. Such flickers of light would also be unique on the world in that they'd exist despite Venus' clouds lacking water, a substance considered key in creating electrical charges.

So, scientists are excited by the possibility of lightning on Venus — but the evidence so far has been circumstantial at best.

And now, a new study suggests lightning might be extremely rare on the planet. Instead, it offers the possibility that meteors burning up high in Venus' atmosphere are very likely responsible for the detected light flashes.
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Fireball

Astronomer captures bright flash in Jupiter's atmosphere

Anjali Thakur
NDTV
Sun, 17 Sep 2023 18:08 UTC
This flash one of the brightest ever recorded on the giant gas planet, was observed last month.
Fireball on Jupiter
© Tweeted by @theshantanumumFlashes like these are caused by asteroids or comets.
An amateur Japanese astronomer Tadao Ohsugi spotted a bright flash in Jupiter's atmosphere. This flash one of the brightest ever recorded on the giant gas planet, was observed last month.

According to a New York Times report, the astronomer sent an email to Dr. Ko Arimatsu, an astronomer at Kyoto University. Upon receiving the email, Dr. Arimatsu put a call out for more information. The media report said that flashes like these are caused by asteroids or comets from the edges of our solar system that impact Jupiter's atmosphere.

Dr. Arimatsu received six more reports of the August 28 flash. Dr. Arimatsu told NYT, "Direct observation of these bodies is virtually impossible, even with advanced telescopes," Dr. Arimatsu wrote in an email. But Jupiter's gravity lures in these objects, which eventually slam into the planet, "making it a unique and invaluable tool for studying them directly."
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Jupiter

Amateur astronomers spot new impact on Jupiter

Andrew Jones
Space.com
Thu, 31 Aug 2023 16:09 UTC
This gas giant regularly absorbs hits from comets and asteroids, protecting inner solar system worlds.
Jupiter
© NASA
Jupiter just got smacked by a small celestial body, according to amateur astronomers.

The impact occurred at 1:45 a.m. Japan Standard Time on Aug. 29 (1645 GMT on Aug. 28). An account affiliated with the Organized Autotelescopes for Serendipitous Event Survey (OASES) project and Planetary Observation Camera for Optical Transient Surveys (PONCOTS) system posted about the event on X, formerly known as Twitter, alerting of a flash observed in Jupiter's atmosphere. The post also called on observers to check their own footage.

MASA Planetary Log later shared footage showing a brief burst of light coming from Jupiter that was associated with an apparent comet or asteroid impact. Another independent observation was made by a Chinese amateur astronomer in the city of Zhengzhou, Henan province, showing a flash in the same spot on Jupiter's dense, turbulent atmosphere.

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Comet 2

New Comet C/2023 P1


Spaceweather.com
Thu, 17 Aug 2023 19:11 UTC
A hyperbolic comet is falling into our solar system. Japanese amateur astronomer Hideo Nishimura discovered it just a few days ago in the constellation Gemini. Although it is relatively dim right now (magnitude +9), Comet Nishimura (C/2023 P1) could soon brighten more than 100-fold to become a naked-eye object in mid-September.
Comet C/2023 P1
© Dan BartlettA sky map with an inset photo of the comet from Dan Bartlett of June Lake, CA
A "hyperbolic comet" is a comet with too much energy to remain trapped inside the solar system. It will visit us only once, with the sun acting as a gravitational slingshot, sending the comet hurtling back into deep space after its flyby. Does that mean Comet Nishimura is an interstellar comet? Not necessarily. It might have come from the Oort Cloud. Indeed, that is more likely.
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Info

Earth's most ancient impact craters are disappearing


American Geophysical Union
Tue, 01 Aug 2023 18:40 UTC
Impact Craters
© Huber et al. (2023), JGR PlanetsImpact craters and their broader structures can be visible in a geologic map, like a bullseye. But what geophysical traces remain at the structure’s outermost edges?
WASHINGTON — Earth's oldest craters could give scientists critical information about the structure of the early Earth and the composition of bodies in the solar system as well as help to interpret crater records on other planets. But geologists can't find them, and they might never be able to, according to a new study. The study was published in the Journal of Geophysical Research Planets, AGU's journal for research on the formation and evolution of the planets, moons and objects of our Solar System and beyond.

Geologists have found evidence of impacts, such as ejecta (material flung far away from the impact), melted rocks, and high-pressure minerals from more than 3.5 billion years ago. But the actual craters from so long ago have remained elusive. The planet's oldest known impact structures, which is what scientists call these massive craters, are only about 2 billion years old. We're missing two and a half billion years of mega-craters.

The steady tick of time and the relentless process of erosion are responsible for the gap, according to Matthew S. Huber, a planetary scientist at the University of the Western Cape in South Africa who studies impact structures and led the new study.

"It's almost a fluke that the old structures we do have are preserved at all," Huber said. "There are a lot of questions we'd be able to answer if we had those older craters. But that's the normal story in geology. We have to make a story out of what's available."

Geologists can sometimes spot hidden, buried craters using geophysical tools, such as seismic imaging or gravity mapping. Once they've identified potential impact structures, they can search for physical remnants of the impact process to confirm its existence, such as ejecta and impact minerals.
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Comet

Best of the Web: Comet 12P/Pons-Brooks explodes and sprouts 'horns'


Space Weather
Tue, 25 Jul 2023 09:41 UTC
A comet with horns? Believe it. On July 20th, something on the surface of Comet 12P/Pons-Brooks exploded, increasing its brightness 100-fold. Debris from the outburst looks like this:
Comet 12P/Pons-Brooks
"Here is a quick view of Comet 12P/Pons-Brooks taken last night between some high clouds," reports Thomas Wildoner of Weatherly, PA. "Just in the last several days, this comet has gone from a star-like appearance to brightening by five magnitudes and now sporting a coma in the shape of two horns."

Comet 12P/Pons-Brooks is famous for exploding. Discovered in 1812 by Pons and discovered again in 1883 by Brooks, the bursty comet visits the inner solar system every 71 years. Since the 19th century at least 7 significant outbursts have been observed, suggesting that it might be a cryovolcanic comet like 29P/Schwassmann-Wachmann.

Comment: For fascinating insight into this phenomena, and more, check out the following articles: Of note regarding the above, is the similarities between asteroids, comets, and even planets; as Pierre Lescaudron writes in Earth Changes and the Human-Cosmic Connection:
Traces of this movement can be found in the late 19th century,when Scientific American published an article stating that Professor Zollner of Leipzig ascribed the 'self-luminosity' of comets to 'electrical excitement.' Zollner proposed that:
...the nuclei of comets, as masses, are subject to gravitation, while the vapors developed from them, which consist of very small particles, yield to the action of the free electricity of the sun
Then, regarding comet tails, the August 11th 1882 issue of English Mechanic and World of Science included the following:
There seems to be a rapidly growing feeling amongst physicists that both the self-light of comets and the phenomena of their tails belong to the order of electrical phenomena.
In 1896, Nature published an article stating:
It has long been imagined that the phenomenon of comet's tails are in some way due to a solar electrical repulsion, and additional light is thrown on this subject by recent physical researches.
[...]

So, comets don't seem to be dirty snowballs after all. From the data presented above, they are glowing chunks of rock. On the other side, asteroids don't seem to be the non-glowing chunks of rocks posited by mainstream science. For example asteroids P/2013 P5 recently puzzled the whole scientific community when it started exhibiting a million miles long glowing tail. To rationalize this oddity official science claimed the asteroid was spinning so fast that it was ejecting tons of dust, while acknowledging that finally the difference between 'comets' and 'asteroids' might not be so clear-cut.1

The fundamental difference between asteroids and comets is not their chemical composition, i.e. dirty, fluffy icy comets vs. rocky asteroids. Rather, as has long been put forward by plasma theorists, what differentiates 'comets' from 'asteroids' is their electric activity.

When the electric potential difference between an asteroid and the surrounding plasma is not too high, the asteroid exhibits a dark discharge mode2 or no discharge at all. But when the potential difference is high enough, the asteroid switches to a glowing discharge mode.3 At this point the asteroid is a comet. From this perspective, a comet is simply a glowing asteroid and an asteroid is a non-glowing comet. Thus the very same body can, successively, be a comet, then an asteroid, then a comet, etc., depending on variation in the ambient electric field it is subjected to.4

Note that a comet can also exhibit the third plasma discharge mode, namely lightning or 'arc discharge mode', which is probably what happened when Comet Shoemaker-Levy entered the vicinity of Jupiter in July 1994:
Note that this comes on the heels of a discovery that Mercury was recently discovered to have a magnificent comet-like tail, and aurora.

The following article from Mr Lescaudron sheds more light on the topic: The Seven Destructive Earth Passes of Comet Venus

And check out SOTT radio's:
Live Science adds more information:
As of July 26, the comet's coma had grown to around 143,000 miles (230,000 kilometers) across, or more than 7,000 times wider than its nucleus, which has an estimated diameter of around 18.6 miles (30 km), Richard Miles, an astronomer with the British Astronomical Association who studies cryovolcanic comets, told Live Science in an email.

The unusual shape of the comet's coma is likely due to an irregularity in the shape of 12P's nucleus, Miles said. The outflowing gas was likely partially obstructed by an out-sticking lobe on the nucleus, which created a "notch" in the expanded coma. As the gas continued to move away from the comet and grow, the notch, or "shadow," became more noticeable, he added. But the expanded coma will eventually disappear as the gas and ice becomes too dispersed to reflect sunlight.

[...]

This is the first major eruption detected from 12P in 69 years, Miles said, mainly because its orbit takes it too far away from Earth for its outbursts to be noticed.
12P/Pons-Brooks comet orbit
© NASA/HorizonsOrbital path of comet 12P/Pons-Brooks
12P has one of the longest known orbital periods of any comet. It takes around 71 years for the floating volcano to fully orbit the sun, during which time it is catapulted out to the farthest reaches of the solar system. The comet is due to reach its closest point to the sun on April 21, 2024 and make its closest approach to Earth on June 2, 2024, at which point it will be visible in the night sky, Spaceweather.com reported. Earthlings could, therefore, get a front-row seat to more eruptions over the next few years.

In December 2022, astronomers witnessed the largest eruption from 29P 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 were able to accurately predict one of 29P's eruptions before it actually happened, thanks to a slight increase in brightness, which suggested more gas was leaking out of the comet's nucleus as it prepared to pop.


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