Fireballs
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Fireball 5

Bright meteor fireball blazes over central Spain

Central Spain meteor
© YouTube/Meteors (screen capture)
This fireball was almost as bright as the Full Moon and overflew Spain on 2020 September 30 at about 1:23 local time (equivalent to 23:23 universal time on September 29). It was generated by a rock (a meteoroid) from an asteroid that hit the atmosphere at around 95,000 km/h. It began at an altitude of about 95 km over the province of Ciudad Real, and ended at a height of around 40 km.

The event was recorded in the framework of the SMART project, which is being conducted by the Southwestern Europe Meteor Network (SWEMN). The event was spotted from the meteor-observing stations located at Sevilla, La Sagra (Granada), La Hita (Toledo), and Sierra Nevada (Granada).


Fireball 3

Hundreds report meteor fireball blazing over Eastern US - UPDATE

AMS event 5441-2020 - Observers map
© AMS (screen capture)AMS event 5441-2020 - Observers map
A streak of bright light, described as a meteor, was sighted in parts of the United States Wednesday morning, according to Twitter users.

The astronomical event was sighted in Cincinnati and in Kentucky. Twitter users reported the sighting before 6:30 a.m.

Many users said it appeared blue or green, then turned orange before it burned out.

"Just happened to look southeast this morning before 6:30 and caught a meteor in the sky. Lit up all red, looked like a contrail fizzling out. Can't remember ever seeing one before - very cool," twitter user Ryan Wichman said.

According to NASA, meteoroids are objects in space that range in size from dust grains to small asteroids. When they enter Earth's atmosphere at high speed and burn up they become meteors. They can become visible fireballs or "shooting stars."


Comment: The American Meteor Society (AMS) has received 264 reports about a meteor fireball seen over DC, IL, IN, KY, MD, MI, NC, NJ, NY, OH, Ohio, Ontario, PA, SC, TN, VA, WI and WV on Wednesday, September 30th 2020 around 10:24 UT.

Update: 1st Oct. 2020

This meteor fireball event has now had 567 reports posted to the AMS website, making it the most widely reported meteor fireball in the US since July 2019.

More videos have been uploaded to the AMS website:






Info

The Younger Dryas impact research debate update

Ice Age Skeletons
© Jonathan Chen / CC BY-SA 4.0Ice Age Diorama. From left to right: Equus hemionus, Mammuthus primigenius, Coelodonta antiquitatis, Bison exiguous skeletal mounts at the Tianjin Natural History Museum.
The Younger Dryas impact hypothesis has received considerable attention since its publication in 2007 in the prestigious peer-reviewed journal PNAS (Proceedings of the National Academy of Sciences). It suggests the Younger Dryas geological period and mini Ice-Age, from around 10,850 to 9600 BC, along with associated megafaunal extinctions and human societal changes, was triggered by a catastrophic cosmic impact, probably with a fragmented comet from the Taurid meteor stream.

As of now, this paper by Richard Firestone, Allen West and Simon Warwick-Smith and colleagues has amassed over 550 citations in Google Scholar - which is a lot! It is on its way to becoming a classic. But it has also received more than its fair share of criticism, mostly sustained from just a handful of vehement opponents. But has any of their criticism stuck? And what is the status of Firestone et al.'s paper today? Has the dust settled on an outcome? Are we there yet?
Evolution of Temperatures
© Evolution of temperature in the Post-Glacial period according to Greenland ice cores/CC BY-SA 4.0Evolution of temperatures in the post glacial period, after the Last Glacial Maximum (LGM), showing very low temperatures for the most part of the Younger Dryas, rapidly rising afterwards to reach the level of the warm Holocene, based on Greenland ice cores.

Fireball 2

Meteor fireball over Spain on Sep. 25

FIREBALL
This bright meteor overflew the south of Spain on 2020 September 25 at about 23:52 local time (equivalent to 21:52 universal time). It was generated by a rock (a meteoroid) from an asteroid that hit the atmosphere at around 39,000 km/h. It began at an altitude of about 80 km over Seville, and ended at a height of around 26 km over Córdoba.

The event was recorded in the framework of the SMART project, which is being conducted by the Southwestern Europe Meteor Network (SWEMN). The event was spotted from the meteor-observing stations located at Sevilla, La Sagra (Granada), La Hita (Toledo), Sierra Nevada (Granada), and Calar Alto.


Info

100 million-year-old meteorite crater discovered Down Under

Ora Banda Impact Crater
© Resource PotentialsA color-coded gravity image of the Ora Banda Impact Crater site. The crater (deep blue) is in the middle of the image.
Gold miners in the Australian Outback recently discovered a gigantic meteorite crater dating to about 100 million years ago, back when dinosaurs roamed the Earth.

Found near the Western Australian town of Ora Banda, the newly dubbed Ora Banda Impact Crater is about 3 miles (5 kilometers) across. This huge hole was likely created by a meteorite up to 660 feet (200 meters) wide, or longer than the length of two American football fields, according to Resourc.ly, a Western Australia news outlet.

When geologists at Evolution Mining, an Australian gold mining company, came across some unusual rock cores at Ora Banda, they called Jayson Meyers, the principal geophysicist, director and founder of Resource Potentials, a geophysics consulting and contracting company in Perth. Meyers examined the geologists' drill core samples, as well as rock samples from the site, and he immediately noticed the shatter cones — telltale signs of a meteorite crash.

Shatter cones form when high-pressure, high-velocity shock waves from a large impacting object — such as a meteorite or a gigantic explosion (such as would occur at a nuclear testing site) — rattle an area, according to the Planetary Science Institute (PSI), a nonprofit group based in Tucson, Arizona, which was not involved with the new find. These shock waves shatter rock into the unique shatter cone shape, just like a mark that a hard object can leave on a car's windshield.

Because "we know they didn't do any nuclear testing at Ora Banda," the evidence suggests that an ancient impact crater hit the site, Meyers told Resourc.ly.

Fireball 5

Meteor fireball streaks over Western Europe

Event 5282-2020 observers map
© YouTube/AMS (screen capture)AMS event 5282-2020 observers map
The American Meteor Society (AMS) have received 120 reports (5282-2020) about a meteor fireball seen over Western Europe (District de Luxembourg, Drenthe, England, Flevoland, Friesland, Gelderland, Groningen, Hessen, Limburg, Mecklenburg-Vorpommern, Niedersachsen, Noord-Brabant, Noord-Holland, Nordrhein-Westfalen, North Holland, Overijssel, Sachsen, Sachsen-Anhalt, Schleswig-Holstein and Vlaande) on Tuesday, September 22nd 2020 around 03:53 UT.


Question

Mystery after 'unbelievably loud bang' heard over Suffolk, England

Framlingham, UK
© Michele Doick/Getty Images
An "unbelievably loud bang" woke up residents across Suffolk this morning, prompting questions over its origin.

The noise was heard by a number of people in towns and villages across the east of the county shortly after 6.30am today.

Residents in Framlingham, Kettleburgh and Saxmundham have all reported hearing the mysterious bang, which sounded "like an explosion".

One dog walker said the noise scared her dog so much it was left shaking.

Another person described the noise as "unbelievably loud" and said it made his house shake.

Comet 2

Strange, glowing ultraviolet aurora detected around a comet

Comet 67P/Churyumov-Gerasimenko.
© ESA/Rosetta/NAVCAMComet 67P/Churyumov-Gerasimenko.
Aurora - the dancing glow of ionised particles in Earth's upper atmosphere - is not unique to our planet.

The phenomenon has been spotted shining in the atmospheres of every other planet except Mercury. Even Jupiter's moons Ganymede and Europa have auroras.

Never, until now, had an aurora been detected on a comet.

But, in a new analysis of data collected by the Rosetta spacecraft, the space around Comet 67P Churyumov-Gerasimenko (67P/C-G) has been observed glowing with far-ultraviolet auroral radiation.

"I've been studying the Earth's auroras for five decades," said physicist Jim Burch of the Southwest Research Institute.

"Finding auroras around 67P, which lacks a magnetic field, is surprising and fascinating."

Auroras are generated by the excitation of charged particles in an atmosphere.

Here on Earth, for instance, the solar wind blows into the magnetosphere and interacts with charged particles there.

These particles rain down into the upper atmosphere and are funneled up the magnetic field lines to the poles, where they manifest as rippling curtains of light.

It works differently on different bodies, though. The auroras of Ganymede and Europa are generated by interactions with Jupiter's magnetic field.

Venus doesn't have a magnetic field of its own that we know of, but interactions with the solar wind creates one strong enough to trigger auroras.

Mars' atmosphere is extremely thin, but its weak magnetic field can support auroras.

Comet 2

New Comet C/2020 S3 (Erasmus)

CBET 4885 & MPEC 2020-S119, issued on 2020, September 20, announce the discovery of a comet (magnitude ~18.5) by Nicolas Erasmus (South African Astronomical Observatory), in four 30-s CCD images taken in 5" seeing on Sept. 17.6 UT with a 0.5-m f/2 Schmidt reflector at Mauna Loa, Hawaii, in the course of the "Asteroid Terrestrial-Impact Last Alert System" (ATLAS) search program. The new comet has been designated C/2020 S3 (Erasmus).

We performed follow-up measurements of this object while it was still on the PCCP webpage.

Stacking of 151 unfiltered exposures, 30 seconds each, obtained remotely on 2020, September 19.1 from L07 (Osservatorio Salvatore di Giacomo, Agerola) through a 0.5 m f/8 Ritchey Chretien + CCD FLI PL4240, shows that this object is a comet with a diffuse coma about 20" in diameter.

Our confirmation image (click on it for a bigger version)

Comet C/2020 S3 Erasmus
© Remanzacco Blogspot

House

Mysterious tremor, deafening bang that 'shook homes' leaves Snowdonia, Wales residents baffled

Woman covering ears
© Ragip Candan
A mysterious tremor was felt by residents on the edges of Snowdonia today.

Debbie Green, who owns a farm near Cwm Silyn, described the noise as "deafening".

The farmer said that she began to feel a vibration in her feet when sat in her living room, but suddenly heard a "massive noise" before her entire house began to shake.

The incident caused her dogs to "kick off" and spooked the horses on the farm who had to be calmed down afterwards.

Other people in the area experienced something similar at 2.10pm today, including Ms Green's neighbour whose house also began to shake inexplicably at the same time.