Meteory, meteoryty, bolidy

[Orionid]

Happy Asteroid Day 2019 with asteroids Brianmay and Grigorijrichters, co-founders of the event
BY GIANLUCA MASI · 06/29/2019

We want to wish “Happy Asteroid Day 2019” to everyone on Earth and have thought that the best way to do this is sharing images we did of asteroids (52665) Brianmay and  (8664) Grigorijrichters, named after two of the co-founder of this global celebration! (...)

https://www.virtualtelescope.eu/2019/06/29/happy-asteroid-day-2019-with-asteroids-brianmay-and-grigorijrichters-co-founder-of-the-event/

[Adam.Przybyla]

Cos bylo widac w Sevilli, predkosc 54k km/godz:
https://www.publico.es/ciencias/meteoro-detectan-bola-fuego-sobrevolando-huelva-sevilla-badajoz-54000-km-hora.html
(chrome)
Z powazaniem
                        Adam Przybyla

[Orionid]

Analiza żelaznych mikrometeorytów  wskazuje, że CO2 przed 2,7 mld lat w ziemskiej atmosferze mógł występować na poziomie  25-50 %.

Meteorites reveal high carbon dioxide levels on early Earth
Matthew Carroll January 29, 2020


Iron micrometeorites, like seen here under a microscope, can provide new clues about the composition of the Earth's upper atmosphere 2.7 billion years ago.  IMAGE: PROVIDED BY ANDREW TOMKINS

UNIVERSITY PARK, Pa. — Tiny meteorites no larger than grains of sand hold new clues about the atmosphere on ancient Earth, according to scientists.

Iron micrometeorites found in ancient soils suggest carbon dioxide made up 25 to 50 percent of Earth’s atmosphere 2.7 billion years ago, and that pressure at sea level may have been lower than today, Penn State researchers said.

The meteorites melted as they streaked through the atmosphere and oxidized as they encountered atmospheric gases. Evidence of the oxidation remains on the tiny fragments that landed on Earth. The samples serve as a unique proxy for conditions in the upper atmosphere, the scientists said.

“This is a promising new tool for figuring out the composition of the upper atmosphere billions of years in the past,” said Rebecca Payne, a doctoral candidate in geosciences and astrobiology at Penn State. Payne is lead author of the study, published recently in the journal Proceedings of the National Academy of Sciences.

The work builds on previous studies of the micrometeorites that suggested free oxygen molecules in the upper atmosphere oxidized the meteorites. Those findings would require oxygen levels on ancient Earth to be near modern day levels, a surprising conclusion that contradicts conditions expected on the young planet, Payne said.

The researchers conducted a new analysis using photochemical and climate models and determined carbon dioxide, not oxygen, likely served as the main oxidant. For this to be possible, they found carbon dioxide had to comprise at least 25 percent of the atmosphere.

Those levels of carbon dioxide would suggest a warm planet, but other climate evidence finds Earth was cool at the time and partly covered by glaciers. Lower nitrogen levels resulting in lower pressure would allow for both high carbon dioxide levels and cool conditions.

“There are data, referenced in our paper, that support lower nitrogen concentrations during this time,” said Jim Kasting, Evan Pugh University Professor in the Department of Geosciences at Penn State and Payne’s adviser. “Our study of micrometeorite oxidation falls in line with that interpretation. The possibility that our major atmospheric gas, nitrogen, was less abundant in the distant past is really intriguing.”

The findings may help reconcile disagreements in previous studies on carbon dioxide in the deep past and climate model estimates, according to the researchers.

Previous estimates of carbon dioxide levels from billions of years ago rely on paleosols, or ancient soils, which may better reflect conditions in the lower atmosphere. Regional differences like weather or ground cover also can impact paleosols samples, and the findings from these studies often contradict each other and climate models, the scientists said.

“It was getting difficult to figure out where the agreement should have been between different paleosol studies and climate models,” Payne said. “This is interesting, because it’s a new point of comparison. It may help us find the right answer about atmospheric carbon dioxide in the deep past.”

Don Brownlee, professor at the University of Washington, also contributed to this research.

https://news.psu.edu/story/605775/2020/01/29/research/meteorites-reveal-high-carbon-dioxide-levels-early-earth

[Orionid]

Hmm, nie znalalem dobrego watku, wiec sprawa laduje tutaj. natknale sie na zdjecia pewnego japonczyka,
jak rozumiem, pan Susumu Okada fotografuje mikrometeoryty, jakie znalazl na Ziemi
Na jego stronie jest wiecej zdjec: https://twitter.com/susumuokada/status/1243830739789066244/photo/2
Z powazaniem
                          Adam Przybyla
Zrodla:
https://www.susumuokada.com/
https://twitter.com/susumuokada

susumu_okada@susumuokada27 marca
Nie poświęcam dużo pracy SNS, ale wychodzę, więc postanowiłem tweetować moją pracę nieregularnie, myśląc, że mogę się trochę pomylić. Z serii <Valueless>. Ta praca to drobny strzał ziaren piasku o grubości 1-2 mm spadających na ziemię. To dzieło, które zdobyło nagrodę Excellence Award w konkursie sponsorowanym przez Canon, New Cosmos of Photography 2018.

https://twitter.com/i/events/1243820880045592576

[Orionid]

W Australii w przeciągu 2 tygodni odnaleziono 2 meteoryty z niedawnych spadków. Jeden z nich jest nietypowy pod względem magnetycznym.

Rock stars – Curtin scientists find two meteorites in two weeks
MEDIA RELEASE Thursday 30 July 2020


Curtin's Dr Hadrien Devillepoix pointing to the meteorite found near Madura

Curtin University researchers have discovered two meteorites in a two week period on the Nullarbor Plain – one freshly fallen and the other from November 2019.

(...) But after a closer inspection, it was evident that the fist-sized, 1.1 kilogram rock we just found was indeed the meteorite we were after,” Dr Devillepoix said.

Dr Devillepoix explained that although the rock was very close to the predicted fall position, the team was not expecting to find it that quickly in this bushy terrain.

“Most meteorites contain a lot of metallic iron, a lot more than normal Earth rocks. This is why meteorites typically attract a magnet, or make a nearby compass ‘go crazy’,” Dr Devillepoix said.

“However the meteorite that we found almost entirely fails the compass test – the compass needle barely gets disturbed, which is really intriguing. The next step for us is to now figure out why this is happening and what is making this meteorite so different to the others we know about.” (...)

“We were able to determine that this meteorite was on an Aten orbit, which means that before it fell to Earth, the meteorite spent most of its time in the innermost Solar System, between Venus and Earth,” Dr Devillepoix said. (...)

Two weeks later, Dr Martin Towner, operations chief of the team, led the six people team to search the site of the November 2019 fall. This fall was North-West of Forrest airport in the middle of the Nullarbor.

After just four hours of searching, they found the 300 gram meteorite that the DFN had seen come in on the night of November 18th, 2019.

This one came from a radically different orbit, pointing to the middle part of the main asteroid belt. The team is now working to uncover what secrets the two rocks hold. (...)
https://news.curtin.edu.au/media-releases/rock-stars-curtin-scientists-find-two-meteorites-in-two-weeks/

[Adam.Przybyla]

2 lipca na japonia widac bylo duza kule ognia, wydaje, se ze udalo sie znalec odlamki meteorytu.




Na szczescie najwiekszy krater, jaki udalo sie znalec japonczykow powstal dawno i nie na Ziemi,
ziemskie meteoryty to jednak w porownaniu do tego mikrusy;-)
A inny ibiekt wykryty na niebie okazal sie balonem od google do lacznosci;-)
Z powazaniem
                         Adam Przybyla
Zrodla:
https://twitter.com/AvellSky/status/1273240969467400193
https://twitter.com/KAGAYA_11949/status/1278391023329140736
https://twitter.com/AvellSky/status/1278990564751376385
https://twitter.com/AvellSky/status/1278893627503022080
https://twitter.com/CfCA_NAOJ/status/1287647326870241280

[Orionid]

Deszcz Perseidów – kiedy obserwować niebo?
BY REDAKCJA ON 11 SIERPNIA 2020

(...)  najwięcej możemy spodziewać się tuż przed świtem 12 sierpnia.

Tegoroczny deszcz Perseidów niefortunnie wypada w ostatniej kwadrze fazy księżyca (47% tarczy Księżyca), co utrudni widok, zmniejszając realną widoczność Perseidów z niemal 100 do około 20 obiektów na godzinę (ZHR). Na szczęście Perseidy są bogate w jasne meteory i bolidy, więc mimo to warto zaobserwować zjawisko. (...)
https://kosmonauta.net/2020/08/deszcz-perseidow-kiedy-obserwowac-niebo/

[Orionid]

Niezabrudzony meteoryt Asuka 12236 jest bardzo niezwykły w swojej klasie.
Został znaleziony w 2012 na Antarktydzie.
Zawiera dwukrotnie więcej aminokwasów od dotychczasowego rekordzisty - meteorytu o nazwie Paris.
Asuka 12236 zawiera też więcej lewoskrętnych wersji niektórych aminokwasów (do budowania białek wykorzystywane są tylko lewoskrętne).

Pristine Space Rock Offers NASA Scientists Peek at Evolution of Life’s Building Blocks
Aug. 20, 2020

(...) On the timeline of the solar system, Asuka 12236 fits in toward the very beginning – in fact, some scientists think that tiny pieces of the meteorite predate the solar system. Several lines of evidence suggest that Asuka 12236’s original chemical makeup is the best preserved in a category of carbon-rich meteorites known as CM chondrites. These are among the most interesting rocks to study for scientists who focus on the origin of life since many contain a highly complex mixture of organic compounds associated with living things.

Scientists have determined the interior of Asuka 12236 is so well-preserved because the rock was exposed to very little liquid water or heat, both when it was still a part of an asteroid and later, when it sat in Antarctica waiting to be discovered. They can tell based on the types of minerals found inside. A dearth of clay minerals is one clue, given that these types of minerals are formed by water. Another clue is that Asuka 12236 has lots of iron metal in it that hasn’t rusted, an indication that the meteorite hasn’t been exposed to the oxygen in water. The rock also contains an abundance of silicate grains with unusual chemical compositions that indicate they formed in ancient stars that died before the Sun began to form. Since these silicate minerals are typically easily destroyed by water, scientists don’t find them in meteorites less pristine than Asuka 12236. (...)

Meteorites like Asuka 12236 are pieces of much larger asteroids. These fragments were flung into the solar system during asteroid collisions more than 4.5 billion years ago and ultimately made their way to Earth’s surface after surviving a fiery descent through our atmosphere. For Alexander and Glavin, these rocks are like history books that fall from the sky and deliver chemical information about the early solar system. Space rocks are the only source of this information, because erosion and plate tectonics on Earth have wiped away the chemical history of our planet. (...)
https://www.nasa.gov/feature/goddard/2020/pristine-space-rock-offers-nasa-scientists-peek-at-evolution-of-life-s-building-blocks

Researchers Find Extraterrestrial Amino Acids in Antarctic Meteorite
Aug 31, 2020 by News Staff / Source

A team of astrobiologists from NASA’s Goddard Space Flight Center and the Carnegie Institution for Science has found a wide diversity of amino acids in Asuka 12236, a carbonaceous chondrite meteorite recovered from the Nansen Ice Field in Antarctica by Belgium and Japan researchers in 2012. (...)
http://www.sci-news.com/space/extraterrestrial-amino-acids-antarctic-meteorite-08796.html

https://www.geekweek.pl/news/2020-08-26/ten-maly-kosmiczny-kamien-odpowie-na-pytania-o-ewolucje-zycia-we-wszechswiecie/

[Orionid]

Interesujące odkrycia m.in. w Australii

Meteorite crater discovered while drilling for gold in outback WA estimated to be 100 million years old
ABC Goldfields / By Jarrod Lucas Posted 1day ago, updated Yesterday at 7:35am

(...)
It is not visible from the surface but electromagnetic surveys, which map the rocks below, suggest the crater has a diameter of around 5 kilometres.

Perth-based geologist and geophysicist, Jayson Meyers, said the asteroid that made the crater would have been at least 100 metres wide.

"Based on its position and levels of erosion and some of the soil that is filling the sides, we estimate it could be around 100 million years old," Dr Meyers told the ABC. (...)
https://www.abc.net.au/news/2020-09-02/new-meteor-crater-discovered-in-wa-100-million-years-old/12620970

https://www.theguardian.com/science/2020/sep/03/massive-meteorite-crater-found-in-western-australia-thought-to-be-100-million-years-old

https://www.msn.com/en-gb/news/world/massive-meteorite-crater-found-in-western-australia-thought-to-be-100-million-years-old/ar-BB18FrsZ

https://www.abc.net.au/news/2020-09-02/new-meteor-crater-discovered-in-wa-100-million-years-old/12620970

Massive meteorite craters found in Western Australia and Central America
Last updated May 20, 2019 at 11:12 am Andrew Masterson

Two studies have identified massive meteorite craters near Perth, and in Central America.

Researchers have discovered two previously unknown massive meteorite craters on Earth, the most recent estimated to have been produced by an impact only 800,000 years ago.

The craters – one in Western Australia and the other in Nicaragua – are revealed in a pair of papers published in the journal Meteoritics and Planetary Science. (...)
https://australiascience.tv/massive-meteorite-craters-found-in-western-australia-and-central-america/

[Orionid]

Meteorites show transport of material in early solar system
NEWS RELEASE 8-SEP-2020 UNIVERSITY OF CALIFORNIA - DAVIS

(...) Yin, UC Davis research scientist Curtis Williams, and their collaborators carried out a detailed study of isotopes from 30 meteorites. They confirmed that they fell into two distinct groups: the non-carbonaceous chondrites as well as other, more common types of meteorite; and the carbonaceous meteorites.

Then they studied individual chondrules from two chondritic meteorites, the Allende meteorite that fell in Mexico in 1969 and the Karoonda meteorite, which fell in Australia in 1930.

These meteorites turned out to contain chondrules from both the inner and outer solar system. Some material from the inner solar system must have managed to cross the Jupiter barrier to accrete with outer solar system chondrules into a meteorite that billions of years later would fall to Earth.

How? There are a couple of possible mechanisms, Williams said.

"One is that there was still movement along the disk midplane, although it should have been stopped by Jupiter," he said. "The other is that winds in the inner solar system could have lofted particles over the Jupiter gap." (...)
https://www.eurekalert.org/pub_releases/2020-09/uoc--mst090820.php

[Orionid]

Nietypowy bolid nad Europą (22.09.2020)
BY KRZYSZTOF KANAWKA ON 27 WRZEŚNIA 2020

(...) Dwudziestego drugiego września o 05:53 CEST nad niebem północno-zachodnich Niemiec, Holandii oraz południowej Wlk. Brytanii zaobserwowano jasny bolid. Smuga świetlna powstała podczas przelotu tego bolidu rozjaśniła dużą część nieba. Po analizie dostępnego materiału z sieci Global Meteor Network, udało się ustalić, że bolid “zanurzył się” w atmosferę prawdopodobnie do wysokości około 91 km. Następnie bolid “uciekł” w przestrzeń kosmiczną. Wyliczona prędkość wejścia obiektu w atmosferę Ziemi to 34,1 km/s. (...)
https://kosmonauta.net/2020/09/nietypowy-bolid-nad-europa-22-09-2020/

 

[Orionid]

Chyba za mało parametrów zostało rozpoznanych, żeby zaliczyć ten przypadek do bliskich przelotów ?
Można powiedzieć: niewykryty, ale zauważony 

[Adam.Przybyla]

Coz takie czasy, gdzies zawsze cos kosmicznego nam upadnie. Japonia zorganizowala wystawe na temat
upadku meteorytu w prefekturze Chiba 2 lipca 2020.
Choc ja mam coraz wieksze watpliwosci, co do naturalnych przyczyn tych upadkow i na
ile te wszystkie upadki to nie przez przypadek jakis kawalek naszej
ludzkiej historii (kawalek burana czy v-2 czy falkona-9;-)), ktory w koncu wrocil  na Ziemie;-)

W kazdym razie japonczycy jakos zawsze potrafili sobie z tym poradzic,
od wiekow wytwarzali np z takich meteorytow miecze;-)
Z powazaniem
                        Adam Przybyla

Zrodla:
https://twitter.com/museum_kahaku/status/1322101064267517954
https://twitter.com/ClosertoSpace/status/1318275370316124166
https://this.kiji.is/665381828416291937
https://twitter.com/RestitutorOrien/status/1322630793982840836
https://twitter.com/Astro_Naoko/status/1310379573213757445
https://www.nippon.com/en/news/yjj2020082600195/
https://twitter.com/NASAWatch/status/1303786123966251015/photo/1
https://twitter.com/PicturesUssr/status/1319305008769163264/photo/1

[Orionid]

Prawdopodobny spadek meteorytu w Szwecji
BY KRZYSZTOF KANAWKA ON 13 LISTOPADA 2020

(...) Siódmego listopada 2020, około 22:30 CET, nad środkową Szwecją zaobserwowano jasny bolid. Obiekt wtargnął pod dużym kątem w atmosferę Ziemi w prędkością około 17 km/s.



Obserwacja bolidu z 7 listopada 2020 – obserwacja z Norwegii / Credits – Steinar Midtskogen

Wyliczenia sugerują, że obiekt miał masę początkową około 3300 kg. (...)
https://kosmonauta.net/2020/11/prawdopodobny-spadek-meteorytu-w-szwecji/

[Orionid]

Bolid nad Czechami
BY KRZYSZTOF KANAWKA ON 15 LISTOPADA 2020

(...) Bolid wtargnął pod dużym kątem w atmosferę Ziemi (ok. 77 stopni) z prędkością 66 km/s. Maksymalna jasność była porównywalna z jasnością Księżyca w pełni. Z wyliczeń wynika, że ślad po bolidzie zniknął na wysokości około 20 km. Masa początkowa bolidu mogła wynieść ponad 20 kg.

Jest możliwe, że niewielkie fragmenty tego bolidu dotarły do powierzchni Ziemi. (...)
(AICR)
https://kosmonauta.net/2020/11/bolid-nad-czechami/