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Comets


Fireball 5

Newly discovered asteroid has a 1-in-600 chance of colliding with Earth, NASA says

The newly discovered asteroid 2023 DW could collide with Earth in February 2046, although the odds of an impact are low.
Asteroid 2023 DW
© Science Photo Library - ANDRZEJ WOJCICKI via Getty Images
An Olympic pool-sized asteroid could collide with Earth in 2046, though the odds are very low.
A newly discovered asteroid may make a perilously close approach to Earth about 20 years from now, with a roughly 1-in-600 chance that the space rock will collide directly with our planet, officials with NASA's Planetary Defense Coordination Office tweeted.

While that's a higher-than-average risk level for near-Earth asteroids, it's still a "very small chance" of impact, NASA wrote — and that risk level is expected to decline as clearer observations of the asteroid become available.

First detected on Feb. 27, the asteroid dubbed 2023 DW is estimated to measure about 165 feet (50 meters) in diameter, or roughly the length of an Olympic-size swimming pool. The asteroid is expected to make a very close approach to Earth on Feb. 14, 2046; as of March 8, the European Space Agency's Near-Earth Object Coordination Centre predicts a 1-in-625 chance of a direct impact, although those odds are being recalculated daily.

Comet 2

Main comet of 2024 named C/2023 A3 Tsuchinshan-ATLAS, could be 6 times brighter than 2020's NEOWISE

C/2023 A3

Trajectory of comet C/2023 A3
The Minor Planet Center (MPC) has given an official name to the comet, which is already being called the main comet of 2024. It received the designation C/2023 A3 ().

C/2023 A3 was first discovered in images taken on January 9 by the Chinese observatory Tsuchinshan (translated as Purple Mountain). On February 22, the ATLAS automated telescope located in South Africa took independent images of the object. The analysis carried out by astronomers showed that it was a comet. C/2023 A3 has a small tail and a very compact coma.

At the moment, C/2023 A3 is located at a distance of 7.3 AU (1090 million km) from the Sun, which exceeds the distance to Jupiter. But it is rapidly approaching the perihelion of its orbit, which will be passed on September 28, 2024. On this day, the comet will fly at a distance of 0.39 AU (58 million km) from the Sun.

Comment: It seems that comets 'exceed expectations' because science's explanation for the behaviour of comets is wrong: For more, check SOTT radio's:


Info

Asteroid impact in slow motion

Researchers at the University of Jena and the German Electron Synchrotron DESY solve a 60-year-old mystery with a high-pressure study.
Barringer crater in Arizona
© US Geological Survey
Barringer crater in Arizona was formed about 50 000 years ago by an approximately 50-meter iron meteorite.
For the first time, researchers have recorded live and in atomic detail what happens to the material in an asteroid impact. The team of Falko Langenhorst from the University of Jena and Hanns-Peter Liermann from DESY simulated an asteroid impact with the mineral quartz in the lab and pursued it in slow motion in a diamond anvil cell, while monitoring it with DESY's X-ray source PETRA III. The observation reveals an intermediate state in quartz that solves a decades-old mystery about the formation of characteristic lamellae in material hit by an asteroid. Quartz is ubiquitous on the Earth's surface, and is, for example, the major constituent of sand. The analysis helps to better understand traces of past impacts, and may also have significance for entirely different materials. The researchers present their findings in the journal Nature Communications.

Asteroid impacts are catastrophic events that create huge craters and sometimes melt parts of Earth's berock. "Nevertheless, craters are often difficult to detect on Earth, because erosion, weathering and plate tectonics cause them to disappear over millions of years," Langenhorst explains. Therefore, minerals that undergo characteristic changes due to the force of the impact often serve as evidence of an impact. For example, quartz sand (which chemically is silicon dioxide, SiO2) is gradually transformed into glass by such an impact, with the quartz grains then being crisscrossed by microscopic lamellae. This structure can only be explored in detail under an electron microscope. It can be seen in material from the relatively recent and prominent Barringer crater in Arizona, USA, for example.
"For more than 60 years, these lamellar structures have served as an indicator of an asteroid impact, but no one knew until now how this structure was formed in the first place," Liermann says. "We have now solved this decades-old mystery."
To do so, the researchers had spent years modifying and advancing techniques that allow materials to be studied under high pressure in the lab. In these experiments, samples are usually compressed between two small diamond anvils in a so-called diamond anvil cell (DAC). It allows extreme pressures - as prevalent in Earth's interior or in an asteroid impact - to be generated in a controlled manner.

Fireball

Meteorite crater discovered in French winery

With the aim of creating an appealing brand, the name of the " Domaine du Météore " winery near the town of Béziers in Southern France points to a local peculiar: one of its vineyards lies in a round, 200-metre-wide depression that resembles an impact crater. By means of rock and soil analyzes, scientists led by cosmochemist Professor Frank Brenker from Goethe University Frankfurt have now established that the crater was indeed once formed by the impact of an iron-nickel meteorite. In doing so, they have disproved a scientific opinion almost 60 years old, because of which the crater was never examined more closely from a geological perspective.

Impact Crater
© Frank Brenker, Goethe University Frankfurt
The “ Trou du Météore ”: The crater at the “ Domaine du Météore ” winery really was caused by a meteorite impact.
Countless meteorites have struck Earth in the past and shaped the history of our planet. It is assumed, for example, that meteorites brought with them a large part of its water. The extinction of the dinosaurs might also have been triggered by the impact of a very large meteorite.

Meteorite craters which are still visible today are rare because most traces of the celestial bodies have long since disappeared again. This is due to erosion and shifting processes in Earth's crust, known as plate tectonics. The "Earth Impact Database" lists just 190 such craters worldwide. In the whole of Western Europe, only three were previously known: Rochechouart in Aquitaine, France, the Nördlinger Ries between the Swabian Alb and the Franconian Jura, and the Steinheim Basin near Heidenheim in Baden-Württemberg (both in Germany ). Thanks to millions of years of erosion, however, for laypersons the three impact craters are hardly recognizable as such.

Fireball

Small Asteroid 2023 CX1 (NEOCP Sar2667) impacted Earth on February 13

On 2023 February 12.8 (20:18:07 UTC), K. Sarneczky found a small asteroid with the 0.60-m Schmidt + CCD of the Piszkéstető Observatory in Hungary (K88 MPC code) that was soon after put on the NEOCP list with the provisional designation Sar2667 for the follow-up by other observers. The object was subsequently imaged by many observers around the world and various impact assessment systems found a 100% impact probability in the area of the English Channel on Feb. 13 between 02 and 04 UTC. This is the second discovery by Sarneczky of an impactor, following the 2022 EB5 event in March 2022.

M.P.E.C. 2023-C103 issued subsequently on 2023 February 13 at 04:13 UT assigned the official designation 2023 CX1 to Sar2667 with the following comment:
K. Sarneczky reported a new NEOCP candidate observed at GINOP-KHK (K88). Rapid follow-up from multiple sites indicated an impact with the Earth's atmosphere on February 13 03:00 UTC near the coast of Normandy, France, as determined by imminent impact monitoring services such as JPL's Scout, ESA's Meerkat and MPC's internal warning system.
Map of the impact zone predicted to occur a few kilometers from French coast, North-East of Le Havre. Click on it for a bigger version.

Asteroid Impact Site
© International Meteor Organization
2023 CX1 was a small Aten asteroid with an estimated size of ~1.0 m (based on the object's absolute magnitude H=32.6).

Attention

Humpback whale washes up dead on New York beach, 10th in 2 months

male humpback whale has washed ashore Lido Beach

Male humpback whale has washed ashore Lido Beach
NOAA reports 178 humpback whale strandings across 13 Atlantic states since 2016

Another whale has washed up dead overnight, making Monday's tragic discovery the 10th loss of the large water mammals in the past two months.

Officials were out on Long Island after a male humpback whale was spotted on Lido Beach before 7 a.m. He was dead by the time he was found.

Crowds gathering to catch the whale throughout the day prompted Hempstead Town crews to erect temporary fencing around the whale. He was so large, a backhoe was needed to move it away from the shore.


Comet

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

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!

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Comet 2

Possible naked-eye comet will visit Earth for first time in 50,000-years

The comet C/2022 E3 (ZTF) could be bright enough to be spotted with the naked eye as it passes the sun and Earth at the end of the first month of 2023.
Comet C/2022 E3 (ZTF)
© Hisayoshi Sato via NASA/JPL-Caltech
An image of the Comet C/2022 E3 (ZTF) taken by astrophotographer Hisayoshi Sato as seen in a still image from a NASA video.
At the start of 2023 Earth will be visited by a newly discovered comet that may just be bright enough to be spotted with the naked eye.

The comet, named C/2022 E3 (ZTF), is currently passing through the inner solar system. It will make its closest approach to the sun, or perihelion, on Jan. 12, and will then whip past Earth making its closest passage of our planet, its perigee, between Feb. 1 and Feb. 2.

If the comet continues to brighten as it currently is, it could be visible in dark skies with the naked eye. This is difficult to predict for comets, but even if C/2022 E3 (ZTF) does fade it should still be visible with binoculars or a telescope for a number of days around its close approach.

According to NASA, observers in the Northern Hemisphere will be able to find the comet in the morning sky, as it moves in the direction of the northwest during January. C/2022 E3 (ZTF) will become visible for observers in the Southern Hemisphere in early February 2023.

Arrow Down

This asteroid impact simulator lets you destroy the world

A web app from Neal.Fun is a choose-your-own-adventure for planetary annihilation.
Impact Site
© Screenshot: Gizmodo/Neal.Fun
I aimed a 1,500-foot iron asteroid traveling at 38,000 miles per hour with a 45-degree impact angle at Gizmodo’s office in Midtown, Manhattan.
Hundreds of thousands of asteroids lurk in our solar system, and while space agencies track many of them, there's always the chance that one will suddenly appear on a collision course with Earth. A new app on the website Neal.fun demonstrates what could happen if one smacked into any part of the planet.

Neal Agarwal developed Asteroid Simulator to show the potentially extreme local effects of different kinds of asteroids. The first step is to pick your asteroid, with choices of iron, stone, carbon, and gold, or even an icy comet. The asteroid's diameter can be set up to 1 mile (1.6 kilometers); its speed can be anywhere from 1,000 to 250,000 miles per hour; and the impact angle can be set up to 90 degrees. Once you select a strike location on a global map, prepare for chaos.

Info

HAARP to bounce signal off asteroid in NASA experiment

HAARP in Alaska
© UAF/GI photo by JR Ancheta
With temperatures falling to 40 degrees below zero, a frosty landscape surrounds antennas at the High-frequency Active Auroral Research Program site in Gakona, Alaska, on Dec. 20, 2022. HAARP conducted a run-through on that date to prepare for the Dec. 27 asteroid bounce experiment.
An experiment to bounce a radio signal off an asteroid on Dec. 27 will serve as a test for probing a larger asteroid that in 2029 will pass closer to Earth than the many geostationary satellites that orbit our planet.

The High-frequency Active Auroral Research Program research site in Gakona will transmit radio signals to asteroid 2010 XC15, which could be about 500 feet across. The University of New Mexico Long Wavelength Array near Socorro, New Mexico, and the Owens Valley Radio Observatory Long Wavelength Array near Bishop, California, will receive the signal.

This will be the first use of HAARP to probe an asteroid.

"What's new and what we are trying to do is probe asteroid interiors with long wavelength radars and radio telescopes from the ground," said Mark Haynes, lead investigator on the project and a radar systems engineer at NASA's Jet Propulsion Laboratory in Southern California. "Longer wavelengths can penetrate the interior of an object much better than the radio wavelengths used for communication."

Knowing more about an asteroid's interior, especially of an asteroid large enough to cause major damage on Earth, is important for determining how to defend against it.

"If you know the distribution of mass, you can make an impactor more effective, because you'll know where to hit the asteroid a little better," Haynes said.

Many programs exist to quickly detect asteroids, determine their orbit and shape and image their surface, either with optical telescopes or the planetary radar of the Deep Space Network, NASA's network of large and highly sensitive radio antennas in California, Spain and Australia.