Proc Natl Acad Sci U S A October 2007 PMID 17901202

Evidence for an extraterrestrial impact 12,900 years ago that contributed to the megafaunal extinctions and the Younger Dryas cooling.

R B Firestone, A West, J P Kennett, L Becker, T E Bunch, Z S Revay, P H Schultz, T Belgya, D J Kennett, J M Erlandson, O J Dickenson, A C Goodyear, R S Harris, G A Howard, J B Kloosterman

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Mentions

193
Peak: 5 in Jul 2022
across 6 sources since Dec 2019

Extended reach

2,137,322
potential audience

Total likes

34,313

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Mentions per month

Dec 2019 – Nov 2025

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AI synopsis

What people are saying

The overall tone reflects strong support for the impact hypothesis, as seen in comments like 'mountain of evidence' and 'cataclysmic events', with some participants referencing scientific studies and geological evidence. The language varies from cautious scientific support to more speculative and dramatic descriptions, demonstrating both interest and engagement with the topic's significance.

AgreementModerate agreement

Most discussions support the idea that the impact hypothesis explains environmental changes and megafauna extinctions, with some urging verification and others reaffirming its significance.

InterestHigh interest

Posts show high curiosity about the subject, with references to scientific evidence, reactions to the paper, and discussions about its implications for Earth's history.

EngagementModerate engagement

Many users cite specific studies, mention related findings, and debate their credibility, indicating a moderate level of deep engagement.

ImpactModerate impact

The discourse suggests the hypothesis influences perspectives on Earth's history and extinction events, though the controversy indicates an ongoing debate rather than decisive impact.

Abstract in brief

  • The text discusses evidence of an extraterrestrial impact event around 12,900 years ago, linked to major environmental changes like the Younger Dryas cooling, megafaunal extinctions, and shifts in human behavior during the end of the Clovis culture.
  • Evidence supporting this impact includes a black carbon-rich layer containing magnetic grains, iridium, microspherules, charcoal, soot, nanodiamonds, fullerenes, and ET helium, which is found across North America and specific geological features called Carolina Bays.
  • The authors hypothesize that a large extraterrestrial object exploded over northern North America, causing environmental disruptions such as ice sheet destabilization, biomass burning, and food shortages, which contributed to the abrupt climatic cooling and mass extinctions.]

Top posts

Most liked on X and Bluesky
アシスタント垢&避難場所
@H860Lrc5aLfsY6B · X

https://t.co/6Y8O9VScVr

Sep 25, 2025 · 5 likes · 2 shares · 13,048 followers View post →
Cornczech-the-Throttled MAGA
@Cornczech · X

https://t.co/Vu2fJDSQS9 A fundie freak job said I was a Satan worshiper because I read research papers - Maybe more people should do their own research and discover the world! (God gave us a brain to USE, by the way)

Jul 19, 2022 · 3 likes · 3,551 followers View post →
Conspiracy, Conjecture and Critical Thinking
@ConspiracyCCT · X

Younger Dryas Impact Hypothesis (YDIH) Update https://t.co/9o57n7Sncg For: https://t.co/Jg2sNYkBVR Paper: https://t.co/Aik4QoTezr Against: https://t.co/f0HQcucsq5 Original paper ('07): https://t.co/uD7My9uWBi What say you?

Jun 23, 2024 · 3 likes · 1 share · 1,320 followers View post →
IO Aircraft Incorporated
@io_aircraft_inc · X

@EpistemiclyRich @jonatanpallesen https://t.co/thP0jRfN7C

Jul 8, 2024 · 3 likes · 1,116 followers View post →
David White
@TemplarScribe · X

@92michael @Third_Eye_Seeks @joerogan @randallwcarlson @JahannahJames @BrightInsight6 @AHC_Channel @ancient_view @HiddenKnowledg9 @hiddenincatours @TheResident @_kez26 @VioletNeill1 @AArchitectsYT @derek_olson_ @Megalith_Hunter @MEGALITHOMANIA @megportal @BeStillandKno12 @MC_Floh Or made them vanish completely, like the Clovis people, and the megafauna extinction that accompanied their disappearance. One of the earliest papers from 2007, now widely cited: https://t.co/x7RoeJx0MG

Jul 24, 2022 · 2 likes · 1 share · 966 followers View post →
Yukon
@whateveruthinck · X

@thesedgehog @boneyardak These bone piles are where the bodies all piled up. Impact event followed by catastrophic flooding. I have seen these type of places all over. See https://t.co/aOP97yIUPL

Mar 8, 2025 · 2 likes · 531 followers View post →

All mentions

マルコ
@G6K5p8 · X

RT @H860Lrc5aLfsY6B: https://t.co/6Y8O9VScVr

Sep 25, 2025 · 2 shares · 891 followers View post →
cocoa10
@coco101010go · X

RT @H860Lrc5aLfsY6B: https://t.co/6Y8O9VScVr

Sep 25, 2025 · 2 shares · 230 followers View post →
アシスタント垢&避難場所
@H860Lrc5aLfsY6B · X

https://t.co/6Y8O9VScVr

Sep 25, 2025 · 5 likes · 2 shares · 13,048 followers View post →
JamesTheNew
@JamesTheNew123 · X

@CQRadio14 @Aesiric_Media @more_amalek Here's a paper on the subject. https://t.co/a3Rmufe8Vz

Aug 27, 2025 · 157 followers View post →
Melián
@juancruzmelian1 · X

Como dije al principio, no estoy suponiendo nada sin respaldo. Teorizando? Puede ser. Dejo fuentes: https://t.co/XWCkqyGFQF https://t.co/u8mjFXNQu4 https://t.co/B9Ufwzh8ZO https://t.co/FbLcUfMKq2

Jun 21, 2025 · 532 followers View post →
Yukon
@whateveruthinck · X

@controscience @boneyardak https://t.co/aOP97yIUPL

Mar 9, 2025 · 1 like · 531 followers View post →
Yukon
@whateveruthinck · X

@thesedgehog @boneyardak These bone piles are where the bodies all piled up. Impact event followed by catastrophic flooding. I have seen these type of places all over. See https://t.co/aOP97yIUPL

Mar 8, 2025 · 2 likes · 531 followers View post →
Damien Bates
@Damo__73_ · X

@JLopean @GrogsGamut The evidence shows the regions that saw rapid climate change during the Younger Dryas also suffered mass extinctions of megafauna. Why you seem to think you know better that the planet's best researchers in this area is beyond me https://t.co/IJeKAXekfi https://t.co/borMTbqgiH

Mar 3, 2025 · 1,515 followers View post →
Yukon
@whateveruthinck · X

@BunnyandThorton 2007 https://t.co/aOP97yIUPL

Feb 19, 2025 · 531 followers View post →
Yukon
@whateveruthinck · X

@infinity888sol @boneyardak Probably charcoal see Firestone's research https://t.co/aOP97yIUPL

Feb 18, 2025 · 1 like · 531 followers View post →
The Big D
@gunclubprez · X

This is the story of the worst day on Earth, and it blows my mind that barely 100,000 people have read it. This paper has been backed up by a mountain of evidence that would put Everest to shame. https://t.co/ZU96DuFj3T https://t.co/IycTO8Jf3b

Jan 25, 2025 · 1 like · 3,149 followers View post →
The Big D
@gunclubprez · X

This is the story of the worst day on Earth, and it blows my mind that barely 100,000 people have read it. This paper has now been backed up by a mountain of evidence that would put Everest to shame. https://t.co/ZU96DuFj3T https://t.co/7Ircu5YgY9

Jan 25, 2025 · 3,149 followers View post →
Figgy Biscuits
@FiggyBiscuits · X

@Pooyamax @MomAngtrades @elonmusk Because civilization could be wiped out on the planet because of an impact or solar flare that triggers earthquakes and volcanoes. https://t.co/GmuQ5KczWG

Nov 23, 2024 · 1,906 followers View post →
Glenn Sandström
@eldmeister · X

https://t.co/ocWof1yelF

Aug 20, 2024 · 2,248 followers View post →
IO Aircraft Incorporated
@io_aircraft_inc · X

@EpistemiclyRich @jonatanpallesen https://t.co/thP0jRfN7C

Jul 8, 2024 · 3 likes · 1,116 followers View post →
thealbedojourney
@albedojourney · X

RT @ConspiracyCCT: Younger Dryas Impact Hypothesis (YDIH) Update https://t.co/9o57n7Sncg For: https://t.co/Jg2sNYkBVR Paper: https://t.co…

Jun 23, 2024 · 1 share · 2,097 followers View post →
Conspiracy, Conjecture and Critical Thinking
@ConspiracyCCT · X

Younger Dryas Impact Hypothesis (YDIH) Update https://t.co/9o57n7Sncg For: https://t.co/Jg2sNYkBVR Paper: https://t.co/Aik4QoTezr Against: https://t.co/f0HQcucsq5 Original paper ('07): https://t.co/uD7My9uWBi What say you?

Jun 23, 2024 · 3 likes · 1 share · 1,320 followers View post →
FrankDoyle
@_frankdoyle · X

@AJA_Cortes Humans did not wipe out all of the megafauna with sticks. There were major cataclysmic events that coincided with the extinction of the megafauna. https://t.co/0kiQ4LcZ82

Jun 6, 2024 · 212 followers View post →
DollyFloss
@wendyro82960600 · X

@Phi61861 @Graham__Hancock Well read this, or if this isn't up to standard try youre own search theres 100s by academics. https://t.co/QpcvRpQZZQ

May 3, 2024 · 2 likes · 149 followers View post →
Citizen of EU
@wavetossed · X

RT @wavetossed: @SunWeatherMan It would be interesting for you to do an AMA specifically on the Creative Society .@CreativeScty, and their…

Apr 27, 2024 · 1 share · 9,495 followers View post →
Citizen of EU
@wavetossed · X

@SunWeatherMan It would be interesting for you to do an AMA specifically on the Creative Society .@CreativeScty, and their so-called CLIMATE MODEL which includes Solar Forcing and evidence of cyclic catastrophe such as this paper: https://t.co/lEwOzf57V3

Apr 27, 2024 · 1 like · 1 share · 9,495 followers View post →
BasedBoyScout
@basedboyscout · X

@creepydotorg 10835 BP - keep in mind people are still arguing about this and have since about 2007 now. https://t.co/Xz0mKr5zIY

Apr 1, 2024 · 1,059 followers View post →
AI APOCALYPSE
@wwbarrett64 · X

https://t.co/vFU0FZCwgd

Mar 23, 2024 · 3 followers View post →
Nicholas
@NicholasGroyper · X

@AdubColtsfan @robbswallace @JenResistedAGN Evidence for an extraterrestrial impact 12,900 years ago that contributed to the megafaunal extinctions and the Younger Dryas cooling https://t.co/k5WVofOrvT

Mar 3, 2024 · 1,502 followers View post →
Ancient Puzzles
@AncientPuzzles · X

@DeDunkingPast @BadScienceNews @DrDavidMiano @MTB_Archaeology @GeorgiaCraters I would check the different papers they have published and look for this: This paper that has nothing to do with the YDIH has this section: https://t.co/8oWZhtFkEM And the original YDIH paper published in the same journal, lacks data availability: https://t.co/gG8FYsat5y https://t.co/w8mnOPKI9Y

Sep 19, 2023 · 1 like · 1,029 followers View post →
KarlB
@KARLBERG_H · X

@BrightInsight6 Obviosly they were superior to us in shaping and transporting ridiculously heavy stones. They wouldn´t do it if it had been too difficult, as it would be with tools they used 3-4000 years ago. The yonger dryas impact ended this Civilization. https://t.co/sOJb357lcS

Aug 28, 2023 · 1 like · 1,867 followers View post →
Movimento EcoSocialista ☮️
@MEcosocialista · X

@Eposmail @Leonardobecchet Ed eccoti i dati (magnetici, polveri, analisi chimiche) che condermano che il Dryas fu causato da un grande meteorite... https://t.co/ORIgiaB2no

Jul 19, 2023 · 6,871 followers View post →
DGonzalez
@MGAERagnarok · X

Muchos, tanto las antiguas tradiciones egipcias, sumerias, vehdicas, etc, hablan de un cataclismo que se dió hace unos 11500 años y fue responsable de la extinción de casi toda la megafauna . https://t.co/ARDAbcjXDP Parece que causado por impacto de un cometa-meteorito. https://t.co/nGu0VFzQjI

Jul 18, 2023 · 239 followers View post →
Dr. Elden Wayne Whalen III, ShD
@wayne_effect · X

https://t.co/GGv0JYKMd3 "Brakenridge (10) postulated that a supernova killed the megafauna and caused the worldwide deposition of the black layer. Clube and Napier (11) proposed ..."

Jun 9, 2023 · 1,267 followers View post →
Patrick Bogaart
@pwbogaart · X

@DanielTuijnman Het originele artikel wel: "an extraterrestrial (ET) impact event at ~12.9 ka, which we hypothesize caused abrupt environmental changes that contributed to YD cooling, ... and rapid human behavioral shifts at the end of the Clovis Period." https://t.co/38ydFxdeCy

May 3, 2023 · 1,279 followers View post →
Skip Intro
@HdZephyr · X

@jordanbpeterson Without the Earth as our mother, there would be no such thing as motherhood at all. But you're probably right about the indigenous and the NA Pleistocene megafauna. possibly a cosmic event might account for some of these extinctions. https://t.co/mmAApVDt5Z

Apr 23, 2023 · 108 followers View post →
Dante Molingner
@Dante_Molingner · X

@_ClimateCraze https://t.co/kYRzZtGetW https://t.co/zkWy0YzwsZ

Apr 19, 2023 · 1,806 followers View post →
J Harlow.⚛️
@jaim_harlow · X

@BrockRiddickIFB @My18019926 all mammals larger than 400 pounds (elephants, sloths, Pleistocene armadillos, and camels all disappeared from North America at that time, along with ALL ‘Clovis culture’ camps. https://t.co/q6CnXNRHKU

Apr 11, 2023 · 6,094 followers View post →
Griff
@GriffsGrotto · X

Article can be read in full here: https://t.co/oZTPzyuNQn Much has been written on the topic since then.

Apr 4, 2023 · 5 followers View post →
David Stig Hansen
@stigemup · X

@sitbedu https://t.co/fGEhVWac5V

Mar 24, 2023 · 3,397 followers View post →
Rod Van Mechelen (maga/backlash)
@rodvanmechelen · X

@clif_high Could the taurid impact that caused the Younger Dryas have been an attack? https://t.co/bDAcC5uts5

Feb 28, 2023 · 1 like · 1,830 followers View post →
原発はいますぐ廃止せよ
@kokikokiya · X

12,900 年前に地球外からの衝突があり、巨大動物の絶滅とヤンガードリアスの冷却に貢献した証拠 https://t.co/37DL6h17iN

Feb 23, 2023 · 2,443 followers View post →
Dr.
@arcanebear · X

@SoilManDan @AncientPuzzles @KUHoopes @joerogan @Graham__Hancock @FlintDibble Awesome, that was easy, these guys will make much better guests on Joe's show. https://t.co/TK8tYQVT5y

Jan 18, 2023 · 17,722 followers View post →
Craig Fontaine
@wovokanarchy1 · X

@pondera_fm @jonkay https://t.co/S8EPxYbb8c

Dec 22, 2022 · 305 followers View post →
Glenn battles anti scientific spanners.
@GlennCarr6 · X

@richardwakelin3 @ChrisBBacon3 @JustinGrant923 @JohnMcGoo5 @Kenneth72712993 @jimdtweet @shicks_sam @BubbasRanch @MikeDel21893959 @NewNormality20 @Moderna5G_666 @aSinister @pauladamsalber1 @dan613 @CrispyCX @mugger124 @MartinJBern @CDMarshall7 @NoelTurner194 @Jeffrey75327765 @WayneAllanH @rln_nelson @wlbeeton @starkicus @variegated2 @Michael_D_Crow @la6uoa @freddie07068768 @MedBennett @automatrix66_KC @Veritatem2021 @0Sundance @Narvuntien @Matt_Clough @Jagster20548365 @robhon_ @Grimasaur @CarrudoDon @ponycar06 @njbtweet @priscian @aaa21usa @RandolphDoGood1 @josephenicholas @RealMikeDelta1 @SumErgoMonstro @BradSchrag @SZOMB @keithamccluskey @Skrued1 Can you concentrate long enough for a science paper? This one also proposes a mechanism for the rapid change. Do you think it was good for life on the planet then? https://t.co/5YUJa2YtFe

Dec 12, 2022 · 734 followers View post →
Tim Heaton
@Heaton_T_J · X

@ismjism @JacquelynGill Jusmusm - If you're taking specifically about the YD impact hypothesis, the original paper was by Firestone et al (PNAS, 2007 https://t.co/2u0yFGIyuP). It was pretty immediately controversial and still is (e.g., Pinter et al., 2011 https://t.co/rr34jofZVg)

Nov 20, 2022 · 208 followers View post →
Cornczech-the-Throttled MAGA
@Cornczech · X

https://t.co/Vu2fJDSQS9 and a paper mentioning the rejection of this work https://t.co/jYJ9sy51kg I saw it MANY times when reading research papers about this certain virus we locked down the world for - https://t.co/7qbHhKjxhO

Oct 21, 2022 · 3,551 followers View post →
Cornczech-the-Throttled MAGA
@Cornczech · X

@chkwingslutz @JesseMock42 I noticed that when I started to read argument papers like these: https://t.co/Vu2fJDSQS9 and https://t.co/jYJ9sy51kg

Oct 17, 2022 · 1 like · 3,551 followers View post →
KarlB
@KARLBERG_H · X

@ceciliawinter Människans intrång i känslig fauna är huvudorsaken. Den senaste massutrotningen inträffade så sent som för 13000 år sedan. Förmodligen därför Gobekli Tepe medvetet lades under jord... https://t.co/sOJb34PJOi

Oct 14, 2022 · 1,867 followers View post →
Cornczech-the-Throttled MAGA
@Cornczech · X

@LastChairbender @conspiracyb0t https://t.co/Vu2fJDSQS9 I have been a BIG believer of "alternate history" "scientists" are STILL fighting against this theory

Jul 25, 2022 · 1 like · 3,551 followers View post →
Violet Neill
@VioletNeill1 · X

RT @TemplarScribe: @92michael @Third_Eye_Seeks @joerogan @randallwcarlson @JahannahJames @BrightInsight6 @AHC_Channel @ancient_view @Hidden…

Jul 24, 2022 · 1 share · 4,830 followers View post →
David White
@TemplarScribe · X

@92michael @Third_Eye_Seeks @joerogan @randallwcarlson @JahannahJames @BrightInsight6 @AHC_Channel @ancient_view @HiddenKnowledg9 @hiddenincatours @TheResident @_kez26 @VioletNeill1 @AArchitectsYT @derek_olson_ @Megalith_Hunter @MEGALITHOMANIA @megportal @BeStillandKno12 @MC_Floh Or made them vanish completely, like the Clovis people, and the megafauna extinction that accompanied their disappearance. One of the earliest papers from 2007, now widely cited: https://t.co/x7RoeJx0MG

Jul 24, 2022 · 2 likes · 1 share · 966 followers View post →
Cornczech-the-Throttled MAGA
@Cornczech · X

https://t.co/Vu2fJDSQS9 A fundie freak job said I was a Satan worshiper because I read research papers - Maybe more people should do their own research and discover the world! (God gave us a brain to USE, by the way)

Jul 19, 2022 · 3 likes · 3,551 followers View post →
Cornczech-the-Throttled MAGA
@Cornczech · X

@IAmEzekiel336 The Sun The year 2030 has meaning to those who believe in cyclical Earth changes and cataclysms. Notice how that year, 2030, is used everywhere by the climate "alarmists" https://t.co/Vu2fJDSQS9 and https://t.co/Gd5fJH0LRA since when does porn found on a PC close a gov. office?

Jul 19, 2022 · 3,551 followers View post →
2 Cent Cup of Joe
@bigjoefisher · X

RT @Cornczech: https://t.co/Vu2fJDSQS9 or https://t.co/7CZaUwVWHA https://t.co/lzudMFJQPl

Jun 16, 2022 · 1 share · 785 followers View post →
Cornczech-the-Throttled MAGA
@Cornczech · X

https://t.co/Vu2fJDSQS9 or https://t.co/7CZaUwVWHA https://t.co/lzudMFJQPl

Jun 16, 2022 · 1 like · 1 share · 3,551 followers View post →
Cornczech-the-Throttled MAGA
@Cornczech · X

@AlexEpstein @BostonGlobe https://t.co/jYJ9sy51kg No, it's more like every 12,000 years or so, the Earth undergoes a major cataclysm - This paper addressed the beginning of the Younger Dryas. https://t.co/Vu2fJDSQS9

Mar 19, 2022 · 3,551 followers View post →
Cornczech-the-Throttled MAGA
@Cornczech · X

@ringinabell I just finished reading "Magicians of the Gods" last week - which prompted me to research the YD and I came across a paper that was submitted about it - https://t.co/jYJ9sy51kg and https://t.co/Vu2fJDSQS9

Mar 16, 2022 · 3,551 followers View post →
Sandbird
@Sandbird_ · X

@mpoumpivol2 Λογικά θα έχεις ακούσει για την περίοδο του Younger Dryas? https://t.co/U8XnKI7EFB https://t.co/b5vvpvod9U Επίσης Doggerland, Göbekli Tepe; Ποτέ δε ξες...That's all I am saying

Mar 8, 2022 · 1,757 followers View post →
Sam Gerrits
@samgerrits · X

@enithka .do doet het nog prima? alleen DOI van dat artikeltje doet het niet. Dit is Firestone et al. 2007. "Evidence for an extraterrestrial impact 12,900 years ago that contributed to the megafaunal extinctions and the Younger Dryas cooling." doi:10.1073/pnas.0706977104 https://t.co/IPR2S0kTRZ

Jun 26, 2021 · 1 like · 14,509 followers View post →