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Fri, 05 Mar 2021
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Comets


Comet 2

New Comet C/2021 C4 (ATLAS)

CBET 4937 & MPEC 2021-D113, issued on 2021, February 26, announce the discovery of an apparently asteroidal object (magnitude ~19) on CCD images taken on Feb. 12.6 UT with a 0.5-m f/2 Schmidt reflector at Haleakala, Hawaii, in the course of the "Asteroid Terrestrial-Impact Last Alert System" (ATLAS) search program. This object has been found to show cometary appearance by CCD astrometrists elsewhere after the object was posted on the Minor Planet Center's PCCP webpage due to its orbit. The new comet has been designated C/2021 C4 (ATLAS).

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

Stacking of 5 unfiltered exposures, 90 seconds each, obtained remotely on 2021, February 22.2 from X02 (Telescope Live, Chile) through a 0.6-m f/6.5 astrograph + CCD, shows that this object is a comet with a compact coma about 8" arcsecond in diameter. (Observers E. Guido, M. Rocchetto, E. Bryssinck, M. Fulle, G. Milani, C. Nassef, G. Savini, A. Valvasori).

Our confirmation image (click on it for a bigger version; made with TYCHO software by D. Parrott):
C/2021 C4 Atlas
© Remanzacco Blgospot

Comet 2

Long-period comet breakup is the origin of the dinosaur extinction says study

A new study blames a comet fragment for the death of the dinosaurs 66 million years ago. But most experts maintain that an asteroid caused this cataclysmic event.
Impact Event
© Roger Harris/Science Source
An artist’s rendering of the impact event 66 million years ago that ended the reign of dinosaurs.
In one searing apocalyptic moment 66 million years ago, Earth was transformed from a lush haven into a nightmare world with a fiery wound that bled soot into the skies. The extraterrestrial object that slammed into our planet spelled doom for dinosaurs and countless other species, even as its fallout opened new niches to our mammal ancestors.

For decades, scientists have debated the identity of the impactor that struck our planet that fateful day, leaving a 90-mile scar called the Chicxulub crater under what is now the Yucatán Peninsula in Mexico.

Although an asteroid remains the leading candidate, a team based at the Center for Astrophysics, in Cambridge, Mass., has proposed that the culprit may have been an icy comet that flew too close to the sun.

When long-period comets from the outer reaches of the solar system approach the sun, they can be torn asunder by the star's immense tidal forces. The resulting shards may have been catapulted across Earth's orbit, providing "a satisfactory explanation for the origin of the impactor" that killed the dinosaurs, according to a study published on Monday in Scientific Reports.

"To this day, the origin of the Chicxulub impactor remains an open question," said Amir Siraj, an undergraduate studying astrophysics at Harvard who led the research. His model, he said, examines "this special population of comets" that could have produced enough shards — of the right size, at the right rate and on the right trajectories — to threaten Earth "in a way that's consistent with current observational constraints."

Comet 2

New Comet C/2021 B3 (NEOWISE)

CBET 4929 & MPEC 2021-C16, issued on 2021, February 04, announce the discovery of a comet (magnitude ~19) in infrared images obtained during Jan. 22 UT with the Near-Earth Object Wide-field Infrared Survey Explorer (or NEOWISE; formerly the WISE earth-orbiting satellite). The new comet has been designated C/2021 B3 (NEOWISE).

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

Stacking of 50 unfiltered exposures, 30 seconds each, obtained remotely on 2021, January 27.1 from X02 (Telescope Live, Chile) through a 0.6-m f/6.5 astrograph + CCD, shows that this object is a comet with a compact coma about 10" arcsecond in diameter. (Observers E. Guido, M. Rocchetto, E. Bryssinck, M. Fulle, G. Milani, C. Nassef, G. Savini, A. Valvasori).

Our confirmation image (click on it for a bigger version; made with TYCHO software by D. Parrott):
Comet C/2021 B3 NEOWISE
© Remanzacco Blogspot

Fireball 5

Loud blast recorded on dashcam as meteorite explodes over Sarawak, Indonesia - Locals felt earth shake

Fireball sonic Boom
© The Star
Kota Kinabalu: The mysterious explosion heard by many in Sipitang, Labuan, Lawas (Sarawak), and parts close to these areas on Sunday (Jan 31) could have been a sonic boom or a meteorite which exploded in mid-air.

The Astronomical Society of Brunei Darussalam (PABD) said it received numerous reports from Bruneians who also heard the mysterious loud noise.

The PABD then issued a notice seeking eyewitness accounts of the phenomenon, which is believed to have occurred at about 11am.

Some Bruneians later shared their experiences and uploaded blurry pictures of what appears to be a fireball trailing smoke to PABD's Facebook page.

Comment: Dashcam footage of the event has just emerged on Twitter:




Fireball 5

Meteor fireball lights up Northern Hungarian skies

Meteor over Hungary
© Daily News Hungray
Thanks to a lucky camera position, the following video captures a fireball flashing over Sokorópátka. According to HVG, an unexpected meteor crossed the sky in Sokorópátka, Győr-Moson-Sopron County this week. One of the users of Időkép, Károly Boráros, sent a video to the portal, as his camera was looking right in the direction of the fireball.

A commenter on YouTube wrote that the meteor could also be seen from eastern Poland. He noticed it at 2 AM as he looked out the window at the landscape, but because of the sudden brightness he didn't know how to identify the phenomenon.

Fireball 5

HUGE meteor fireball lights up southern China's dark morning skies

Fireball over Yushu City
© Weibo
This shot of the meteor was taken from a plane.
A suspected low-flying meteor has lit up the sky in northwestern China's Yushu City on December 23.

Video from the event in the city in China's Qinghai Province showed a bright fireball streaking across and lighting the dark sky.

According to reports, the fireball was probably a bolide and it might have dropped several meteorite fragments somewhere in the area.

A bolide is a very bright meteor.

Comment: The Daily Mail provides a few more details of the awesome event:
In another piece of footage, the burning object is seen descending quickly towards hills and fields.

In a third clip, the fireball becomes brighter and bigger as it approaches the ground.

Dan Ba, a local, said he witnessed the fireball while taking his child to school.

'It started very small, but three minutes later it became very big and bright,' the parent told Pear Video.
fireball china decemeber 2020
Yu Jun, chief writer of Chinese science website Guokr, told Beijing News that the fireball looked like a bolide, which is a very bright meteor.

The Nanxiang County Government told Red Star News that it had heard of the matter but was unclear of the details.
It brings to mind the spectacular fireball that roared through Russia's skies on February 15th, 2013, which SOTT reported on at the time: Fireball explodes over Russian city: Widespread panic and structural damage, Thousand people injured

Although there have been a great many smaller events since then, as recorded in our Fire In The Sky section.

See also: Something Wicked This Way Comes

And check out SOTT radio's: More footage and data is emerging on Twitter:






Christmas Lights

Stunning light pillars illuminate night sky in Chinese city

Light pillars in China
© Pear Video

Residents in a northern Chinese city have been stunned by a spectacular optical phenomenon illuminating in the night sky.

Incredible footage shows dozens of colourful light beams appearing on Saturday evening in Inner Mongolia region's Genhe, a city dubbed 'China's pole of cold'.

Millions of social media users were also left in awe at the extraordinary scene, known as light pillars or sun pillars, caused by a bright light source reflected off falling ice crystals in cold weather.


Info

Follow-up on recent NEO objects

Below you can find a selection of some objects for which we recently made follow-up observations at the "Osservatorio Salvatore di Giacomo, Agerola, ITALY" (MPC code L07; Observers E. Guido, A. Catapano, F. Coccia) while they still were on the NEOCP list. More details about the telescope, the magnitude, number of images & exposition, asteroid speed & PA etc. are on the images. Click on each image for a bigger version. All the processing has been made with TYCHO software by D. Parrott.

2020 VX5 (neocp designation C3WZUQ2) is an Apollo-type asteroid discovered by G96 Mt. Lemmon Survey on November 15, 2020. This asteroid has an estimated size of 55 m - 120 m (H=23.4) and it had a close approach with Earth at about 29 LD (Lunar Distances = ~384,000 kilometers) or 0.074 AU (1 AU = ~150 million kilometers) at 1950 UT on 11 Nov. 2020.
2020 VX5
© Remanzacco Blogspot

Fireball 5

Tunguska explosion in 1908 caused by asteroid grazing Earth says new theory

A new theory explains the mysterious explosion in Siberia, scientists say, suggesting Earth barely escaped a far greater catastrophe.
Asteroid
© Dotted Yeti/Shutterstock
In the early morning of June 30, 1908, a massive explosion flattened entire forests in a remote region of Eastern Siberia along the Tunguska River. Curiously, the explosion left no crater, creating a mystery that has puzzled scientists ever since — what could have caused such a huge blast without leaving any remnants of itself?

Now Daniil Khrennikov at the Siberian Federal University in Russia and colleagues have published a new model of the incident that may finally resolve the mystery. Khrennikov and co say the explosion was caused by an asteroid that grazed the Earth, entering the atmosphere at a shallow angle and then passing out again into space.

"We argue that the Tunguska event was caused by an iron asteroid body, which passed through the Earth's atmosphere and continued to the near-solar orbit," they say. If they are correct, the theory suggests Earth escaped an even larger disaster by a hair's breadth.

First some background. Scientists have long speculated on the cause of the Tunguska impact. Perhaps the most widely discussed idea is that the explosion was the result of an icy body, such as a comet, entering the atmosphere. The ice then rapidly heated up and evaporated explosively in mid-air but without ever hitting the ground.

Fireball 4

Meteor fireball lights up Mexican skies and rains fire on northern states

Meteor Fireball
© AMS Meteors Org
Residents across northeastern Mexico were stunned when a green-hued fireball lit up the night sky on Tuesday. Authorities reported that the fiery debris caused localised bushfires in the vicinity.

Reports came flooding in from across the northern state of Nuevo Leon after the suspected meteorite streaked across the sky at approximately 22:14 local time on Tuesday night.

Eyewitness and doorbell cam videos captured the intensity of the fiery phenomenon as it burned bright through the darkness.