新仙女木撞击假说账本

地层视图是年代学,也是这台台子上最公平的一项检验,因为它用的不是任何别人的规矩,正是支持方自己的。左边是你所选遗址的地层柱:有黑垫层的画出黑垫层,其下是被主张的界线层,以及它实测到的那些标志物。右边是全部遗址同时在场,每一个都按它已发表的年代区间,画在假说所主张的那个百年窗口上。然后是那个开关:建模年代,来自支持方的贝叶斯分析;或者直接测在层本身上的年代。角落里的计数每帧重算,而它变化很大。

撞击体视图是物理发生的地方。挑一个天体,或者用直径、速度、入射角与成分自己拼一个,然后看着它进入大气:它在哪个高度解体、是在空中炸开还是落到地面、以及如果落地,它会留下多大的坑。旁边立着五条这个天体必须同时满足的要求,每一条都是算出来的而不是断言的,每一条都写明它为什么过了或没过。它们互相拉扯,而没有任何一档能点亮超过两条。

账本视图是记录本身:十五条被主张的证据,每一条都标着它在独立检验之后的状态,并附一份按类别实时统计的计数。选中任意一行,一侧是当年的主张,另一侧是后来的检验;凡是有数字的,都画在对数图上,因为那些分歧跨着数量级。每千克八百颗对上零。克洛维斯地面上的铱,对上二十米外那条现代河床里更多的铱。

档案视图把 2007 到 2026 摆上一条断轴时间线:那条主张、两年后第一次失败的复现、再四年后的那首安魂曲、挺住了的那道铂峰、年代学审计、最后被证明属于古新世的那个坑、作者名单里有铂峰发现者本人的那份二百九十三页否定论文,以及 2026 年 2 月的两次撤稿。下方等大悬挂两张卡。其中一张很短,但它不是空的。

这座台站已经建过好几台「误认物理」的仪器:INST-42 火流星再入把一列火流星读成飞行器,INST-43 莫古尔计划把一列气球读成飞碟,INST-35 岁差与猎户座关联把三座金字塔读成一张星图。那几台的共同点是:被解释的对象是普通的,而解释是超常的。这一台不一样,而这正是它值得建的原因。

新仙女木撞击假说不是一个边缘主张。它 2007 年发表在 PNAS 上,有二十六位署名作者,提出的是一件具体、有年代、可被证伪的事,并附上一份任何人都能自己去找的物理标志物清单。它被认真对待,被认真检验,而检验的结果是一场极不寻常的公开解体:同一个测出最强证据的人,如今是那篇综合否定论文的合著者;两篇 2025 年的论文在 2026 年 2 月被撤稿;而唯一被提出过的候选陨石坑,比压在它上面的那片冰盖还老了五千八百万年。把这些做成仪器,不是为了嘲笑一个假说。这条档案里真正的主题不是彗星,是一条推理链在什么地方断掉,以及一个无法解释的测量与一个特定解释之间的区别:那道铂峰至今仍然真实、仍然没有公认的成因,而这两件事并不互相支持。

三台机器驱动这台仪器,而三台上的每一个数字,要么是已发表的,要么是已发表数字的算术推论。

E = (π/12)ρL³v² · z_b = z* − 2H·ln(1 + (l/2H)√(f²−1)) · D = 1.161(ρᵢ/ρₜ)⅓L^0.78 v^0.44 g^−0.22 sin(θ)⅓ · C_Pt = (M·f/A⊕)/(a·ρ_ice·N)

年代学那台机器最简单,也最能说明问题。它对每个遗址只问一个问题:它已发表的年代区间,与假说所主张的那个窗口有没有重叠?在支持方的贝叶斯年代下,十五个里有十五个有,那层界线看上去就是四大洲上的同一个瞬间。切到直接测在层上的年代,十个里有四个。洛默尔自己的炭屑老了五百年。奎察奥湖重算之后差了好几千年。而提供了有史以来最高微球粒计数的盖尼,它的碳质球粒被定年为距今 207 碳十四年。同时性是被那个模型造出来的,不是在地里找到的,而你可以用一个开关亲眼看着它发生。

然后是精度旋钮,这是这里最公平的一样东西。肯尼特等人发表过他们自己的定年标准:碳十四精度优于一百年。把它用上。随着不确定度超过阈值,遗址一个个从图上掉下去,那套语料就空了。这一点要紧,因为好几个建模区间大得惊人:梅尔罗斯那个跨 9,475 年。这么宽的区间,你把它指向哪个窗口它都能重叠上,所以把它算作一次命中,并不能证明任何事。

撞击台子用的是 Collins、Melosh 与 Marcus 2005,按原样使用。动压对上材料强度给出解体高度;煎饼模型把碎块摊开,并决定这个天体是炸开还是落地;π 群标度给出陨石坑。只需要一处更正:他们的式 20 在排版中丢了一个括号,而只有更正后的形式能复现他们自己的表 6,并且复现得精确。这台台子同样把车里雅宾斯克算成 0.52 兆吨、在 31 公里处炸开,对上已发表的 500 ± 100 千吨与约 29.7 公里。

铂那条链只有四行算术,而它合到了它自己的源头上。拿撞击体的质量,乘以其成分对应的铂含量,摊到整个地球,再除以尖峰持续那二十一年里在冰盖顶上积起来的冰。从实测的 82.2 万亿分率反着算回去,它给出一个约 830 米的铁质天体,对上佩塔耶夫等人在报告这次测量的那同一篇论文里写的约 0.8 公里。没有任何一项为了让它们对上而被拟合过。这就是他们自己做过的那套计算,也正是他们自己那篇论文断定「应该存在一个几公里的坑」、并指出「并未找到」的原因。

而那五条要求才是重点。送出那道铂:需要一公里的铁。不留下坑:需要小它一百倍的东西。烧掉一片大陆:需要比前者还大得多的东西,而博斯洛的反驳更狠:要把冲击波铺那么远,得在约五百公里高处引爆,而那里什么都炸不起来。在两万年里出现得过来:给尺寸封了顶。以及让地球冷上 1,193 年,这一条在任何尺寸下都买不到,因为所有已发表的平流层滞留时间都以年计。把直径旋钮扫一遍,没有任何取值能同时满足头两条,而它们相差四个数量级。

已发表的遗址年代、那次铂测量、冰芯年代学、海华沙的定年,以及双方各自的复现计数,都完全按记录给出的样子使用。那些主张与那些检验,包括 2026 年的两次撤稿与对撤稿表示不同意的作者,只引用,不解读。撞击体台子算出的一切,都由仪器上署名的方程与常数建模而来,而你可以去动其中任何一项,看着答案跟着动。台子拒绝做的事,是把一个无法解释的测量换算成对某个特定解释的支持。那道铂峰是真的,而它的成因确实不明。这是两件分开的事实,而把它们分开,正是这整套练习的意义。

其中两个改变遗址的定年方式,四个改变那个天体。还有一个什么都改变不了,而那正是发现本身。

• 建模年代 对 直测年代。这台仪器上后果最重的一个开关。建模那一栏是支持方自己的贝叶斯输出:12 个国家、23 个剖面的 354 个年代,被收进一个百年宽的窗口。直测那一栏是直接测在层本身上的东西。两者都已发表,两者都随台发布,而仪器把它们并排画出来,不替你选。
• 要求的精度,从 ±2,500 年收到 ±30 年。把年代精度不如阈值的遗址全部滤掉。支持方自己发表的标准是优于 100 年。把它用上并不是不友好;这只是照他们自己的话办事,也正是梅尔罗斯那个 9,475 年宽的区间不该算作一个百年窗口上的命中的理由。
• 八个真实天体,从车里雅宾斯克到希克苏鲁伯。四公里以上的费尔斯通彗星、佩塔耶夫的 0.8 公里铁陨星、供碎片群方案用的单块金牛座碎片、海华沙撞击体,以及四个后果确实已知的天体,好让你拿这台台子去对现实。八个里没有一个能满足超过两条要求。
• 直径,从十米到二十公里。要紧的那一个,也是最清楚地展示那把老虎钳的那一个。能量与送出的铂都按它的立方走;你欠下的坑按它的 0.78 次方走;而复现间隔陡峭上升。在 100 米到 2 公里之间慢慢拖,看头两条要求怎样交替,却始终没有同时被满足过。
• 速度与入射角。速度从 11 km/s 这个逃逸速度下限,到 72 km/s 的迎头长周期彗星。能量按平方走,但铂的投送并不在乎这些质量来得多快。入射角自水平面量起;低角度入射穿过更多空气、解体得更高,而 45° 是随机撞击最可能的角度。
• 成分,它同时决定密度与铂含量。彗星约含 0.47 ppm 铂,球粒陨石 0.93,而像西霍特-阿林那样的岩浆型铁陨星约 30。最后这个数字,正是冰芯测量把这个假说往铁质天体上推的原因,也正是「铁质天体恰恰是那个不可能空爆的天体」的原因。

七条主张,连同是谁提出的、今天落在哪里。一条是实测且无人质疑的。两条有争议,而其中只有一条与彗星有关。四条已被否定,其中两条的决定性结果来自假说自己的支持者。

1. 先从这条主张最强的版本开始。地层视图,建模年代,精度全开。十五个遗址里,十五个碰到那个窗口。这确实是一个惊人的结果,而它值得在被动任何手脚之前,先以全强度被看见一次。
2. 现在切到直测年代。一次点击。看着洛默尔、奥门与奎察奥湖跳出窗口,而盖尼干脆飞出坐标轴。没有任何东西被重新诠释;这些只不过是测在层上、而不是围绕层建模出来的年代。
3. 把精度旋钮放到 ±100 年,也就是支持方自己的标准。图空了。然后问自己:一个宽 9,475 年的区间与一个百年窗口重叠,这算一个数据点,还是一件人造物?
4. 载入佩塔耶夫的铁陨星,把五条要求都读一遍。它几乎就送得出那道铂,而这正是它当初被提出来的原因。然后读第二条:一个十七公里的坑,而那个年代上任何地方都不存在这样的坑。
5. 现在把直径往下拖,直到那个坑有可能藏得住。一边拖一边看铂的读数崩掉。不存在任何一个直径能让两条同时变绿。这件事请自己做一遍,别听我说;它大约花五秒,而它就是全部的论证。
6. 把费尔斯通的彗星按原尺寸载入,读一读复现间隔。每一千三百万年一次,也就是过去两万年里百分之零点几的机会。而它还是点不着一片大陆。
7. 打开第五条要求,并注意没有任何旋钮能影响它。十五年的气溶胶,对上 1,193 年的冷期。任何撞击式解释都必须绕道海洋,而一旦你承认了这一点,融水不用撞击也能干同样的活。
8. 去账本里选中微球粒。同一批沉积物,两个实验室,每千克八百颗对上零。然后选中铱,并注意遗址旁边那条现代河床里的铱,比克洛维斯地面上的还多。
9. 选中那道铂峰,读一读检验那一栏。这是唯一挺住的一行,而那段文字取自报告它的那篇论文。去读它自己的作者关于陨石坑与野火所下的结论。
10. 在档案处收尾,把那两张卡并排读。如果你带着「这整件事都是胡说」的印象离开这台台子,那你冲过头了。冰里确实有东西,而没有人知道是什么把它放进去的。

在实测、档案所记、这里所建模、以及读法之间的诚实界线:

一句话: 每一个遗址年代、82.2 ppt 的铂峰、由冰芯数层得到的 1,193 年时长、海华沙的 5,799 万 ± 54 万年,以及双方各自的复现计数,是记录加简单算术,你可以在台子上核对;那些主张、那些检验、2026 年的两次撤稿与表示不同意的作者,按记录引用并标注「记录」;进入、空爆、陨石坑、热辐射、通量与铂的全部计算,由 Collins/Melosh/Marcus 2005 与已发表的撞击通量「建模」而来,其中一处排版更正已在仪器上标明,而铂那条链未经任何拟合就合到了它自己源论文的推断上;至于究竟是什么造成了那道铂峰,那是一种读法,台子为它等大悬挂两张卡,不添第三张。把钟跑一遍,把撞击体造出来,然后找到断掉的那一条要求。

• Firestone, R. B. et al. (26 authors), "Evidence for an extraterrestrial impact 12,900 years ago that contributed to the megafaunal extinctions and the Younger Dryas cooling," PNAS 104(41):16016-16021 (2007). Seven markers in a layer averaging 3 cm thick; ten Clovis-age sites plus fifteen Carolina Bays; microspherules averaging 390/kg and reaching 2,144/kg at Gainey; iridium in magnetic grains at 7 of 12 sites from 2 to 117 ppb, and in bulk sediment at 5 of 12 from 0.5 to 3.75 ppb, with the paper's own stated uncertainties of ±50-90%.
• Surovell, T. A., Holliday, V. T., Gingerich, J. A. M., Ketron, C., Haynes, C. V. Jr., Hilman, I., Wagner, D. P., Johnson, E. & Claeys, P., "An independent evaluation of the Younger Dryas extraterrestrial impact hypothesis," PNAS 106(43):18155-18158 (2009). Seven sites resampled by the same protocol, two of them Firestone's own: zero microspherules at Blackwater Draw where about 800/kg were reported, and none at all at Topper. "We were unable to reproduce any results of the Firestone et al. study and find no support for Younger Dryas extraterrestrial impact." The counter-replication is LeCompte, M. A. et al., PNAS 109:E2960 (2012), which recovered spherules at 624 and 260 per kg while conceding the peaks "are not reliably correlated with... the onset of the Younger Dryas" and that the spherules "are not cosmic".
• Haynes, C. V. Jr. et al., PNAS 107:4010 (2010): iridium at Murray Springs measured at 64 ± 22 ppb on the Clovis surface against 72 ± 30 ppb in the modern Curry Draw streambed. "We do not observe a LYDB Ir anomaly relative to the local geological background."
• Kennett, D. J. et al., "Nanodiamonds in the Younger Dryas boundary sediment layer," Science 323:94 (2009): cubic nanodiamonds and n-diamonds at 10 to 3,700 ppb by weight, present "in this boundary layer but not above or below". Daulton, T. L., Pinter, N. & Scott, A. C., PNAS 107:16043 (2010) found none, only graphene and graphene/graphane-oxide aggregates. Daulton, T. L. et al., Journal of Quaternary Science 32:7-34 (2017): "We find no evidence for lonsdaleite in YDB sediments and find no evidence of a spike in nanodiamond concentration at the YDB layer."
• Bement, L. C. et al., PNAS 111:1726 (2014), the proponent-led Bull Creek study that confirmed a boundary nanodiamond spike and then found an equal spike in late-Holocene-to-modern deposits: "The second spike of n-diamonds indicates that high levels of nds are not unique to the YDB." Thirty-one of forty-nine samples contained none at all, so no background level exists to compare against.
• Kennett, J. P. et al., "Shock-synthesized hexagonal diamonds in Younger Dryas boundary sediments," PNAS 106:12623 (2009), the lonsdaleite claim at Arlington Canyon. Refuted crystallographically by Daulton et al. 2017: the published lattice image shows two differently oriented sets of 2.06 Å {002} planes, and "no crystallographic zone axis of lonsdaleite exists that can display two differently oriented sets of 2.06 Å {002} planes because there is only one such set of planes in the structure." van Hoesel, A. et al., PNAS 109:7483 (2012) found cubic nanodiamond at Aalsterhut and no lonsdaleite.
• Petaev, M. I., Huang, S., Jacobsen, S. B. & Zindler, A., "Large Pt anomaly in the Greenland ice core points to a cataclysm at the onset of Younger Dryas," PNAS 110(32):12917-12920 (2013). GISP2 ice from 1,719.875 to 1,709.000 m at 2.5-4.6 years per sample; platinum rising "by at least 100-fold over ~14 y" and falling back over ~7 y; peak 82.2 ppt against an interval mean near 3.6; Pt/Ir at the peak of 1265. The paper's own arithmetic and conclusions: the platinum budget "would require an iron meteorite like Sikhote-Alin of ~0.8 km in diameter"; "the event is expected to form a crater of a few kilometers in diameter. No such crater at YDB has been found so far"; and such a body "is unlikely to result in an airburst or trigger wide wildfires proposed by the YDB impact hypothesis". The platinum precedes the ammonium/nitrate burning spike by about 30 years.
• Moore, C. R. et al., "Widespread platinum anomaly documented at the Younger Dryas onset in North American sedimentary sequences," Scientific Reports 7:44031 (2017): 11 sites, 199 samples, YDB mean 6.0 ppb against a 0.3 ppb background, range 0.3 to 65.6 ppb. Two replicates of the same Flamingo Bay sample returned 6.4 and 65.6 ppb. Sun, N. et al., Science Advances 6:eaax8587 (2020) at Hall's Cave found five osmium enrichments spanning about 4,000 years with a volcanic rather than meteoritic isotopic signature.
• Bunch, T. E. et al., PNAS 109:E1903 (2012) and Moore, A. M. T. et al., Scientific Reports 10:4185 (2020), the Abu Hureyra meltglass at 1.6 wt% of bulk sediment with mineral assemblages implying a minimum 1,720 °C ranging above 2,200 °C. Thy, P., Willcox, G., Barfod, G. H. & Fuller, D. Q., Journal of Archaeological Science 54:193-209 (2015) found the same 1-10 mm siliceous scoria droplets at four early Holocene sites in northern Syria, always associated with buildings destroyed by fire, with building earth melting partially well below 1,200 °C.
• van Hoesel, A. et al., "A search for shocked quartz grains in the Allerød-Younger Dryas boundary layer," Meteoritics & Planetary Science 50(3):483-498 (2015): eleven sites searched, exactly one grain with diagnostic planar deformation features, healed and rounded by transport, and therefore probably eroded from a much older structure.
• The 2026 retractions: Kennett, J. P. et al., "Shocked quartz at the Younger Dryas onset (12.8 ka)," PLOS ONE (2025), retracted 11 February 2026 (PLOS ONE 21(2):e0342620) over an age model whose dates "range from centuries before and after the Younger Dryas onset" and over sampling that left most of the core untested; and Moore, C. R. et al., the Baffin Bay paper, PLOS ONE 20(8):e0328347 (2025), retracted the same day (e0342613) over citations that did not support their statements and over chronology and calibration problems. Several authors did not agree with the retractions.
• Kjær, K. H. et al., "A large impact crater beneath Hiawatha Glacier in northwest Greenland," Science Advances 4:eaar8173 (2018): 31.1 ± 0.3 km in diameter beneath up to 930 m of ice. The paper states "The age of this impact crater is presently unknown" and makes no Younger Dryas claim. Kenny, G. G. et al., "A Late Paleocene age for Greenland's Hiawatha impact structure," Science Advances 8:eabm2434 (2022): shocked zircon U-Pb at 57.99 ± 0.54 Ma.
• Kennett, D. J. et al., "Bayesian chronological analyses consistent with synchronous age of 12,835-12,735 Cal B.P. for Younger Dryas boundary on four continents," PNAS 112:E4344 (2015): 354 dates from 23 stratigraphic sections in 12 countries. Meltzer, D. J., Holliday, V. T., Cannon, M. D. & Miller, D. S., "Chronological evidence fails to support claim of an isochronous widespread layer of cosmic impact indicators dated to 12,800 years ago," PNAS 111:E2162 (2014): "only three of those sites are dated to this window of time... Either there were many more impacts than supposed, including one as recently as 5 centuries ago, or, far more likely, these are not extraterrestrial impact markers." The Gainey carbon spherules date to -135 ± 15 and 207 ± 87 14C BP.
• Holliday, V. T., Daulton, T. L., Bartlein, P. J., Boslough, M. B., Breslawski, R. P., Fisher, A. E., Jorgeson, I. A., Scott, A. C., Koeberl, C., Marlon, J. R., Severinghaus, J., Petaev, M. I. & Claeys, P., "Comprehensive refutation of the Younger Dryas Impact Hypothesis (YDIH)," Earth-Science Reviews 247:104502 (2023). Thirteen authors, 293 pages in pre-proof, seventeen sections: "We demonstrate that research in numerous fields has shown the YDIH should be rejected," and, measured against the proponents' own published dating standards, "No sites used to support the YDIH meet these standards." Note that Michail Petaev, who measured the platinum spike, is among the authors. The exchange continues: Sweatman, M. B., Powell, J. & West, A., Earth-Science Reviews 258:104960 (2024); Holliday et al., Earth-Science Reviews 258:104961 (2024), "We stand by our original review." Most proponent replies now appear in Airbursts and Cratering Impacts, a journal launched by the Comet Research Group itself.
• Pinter, N., Scott, A. C., Daulton, T. L., Podoll, A., Koeberl, C., Anderson, R. S. & Ishman, S. E., "The Younger Dryas impact hypothesis: A requiem," Earth-Science Reviews 106(3-4):247-264 (2011). Pigati, J. S. et al., "Accumulation of impact markers in desert wetlands and implications for the Younger Dryas impact hypothesis," PNAS (2012): elevated iridium, magnetic spherules and titanomagnetite at 10 of 13 black-mat sites aged from about 6 ka to over 40 ka, in the American Southwest and the Atacama.
• Haynes, C. V. Jr., "Younger Dryas 'black mats' and the Rancholabrean termination in North America," PNAS 105:6520 (2008): 97 geoarchaeological sites examined, black mats at about two thirds of them, formed as wet-meadow soils, algal mats and pond sediments with 0.05 to 8% organic carbon by rising water tables. Haynes' own position: "I remain skeptical of the ET impact hypothesis."
• Waters, M. R., Stafford, T. W. Jr. & Carlson, D. L., "The age of Clovis, 13,050 to 12,750 cal yr B.P.," Science Advances 6(43):eaaz0455 (2020), from 32 radiocarbon ages at 10 sites. Buchanan, B., Collard, M. & Edinborough, K., "Paleoindian demography and the extraterrestrial impact hypothesis," PNAS 105:11651-11654 (2008): a nearly featureless summed radiocarbon curve from about 15,000 to 9,000 cal BP with no bottleneck at 12.9 ka. Broughton, J. M. & Weitzel, E. M., Nature Communications 9 (2018) for the mixed and taxon-specific causes of the extinctions.
• Collins, G. S., Melosh, H. J. & Marcus, R. A., "Earth Impact Effects Program: A Web-based computer program for calculating the regional environmental consequences of a meteoroid impact on Earth," Meteoritics & Planetary Science 40:817-840 (2005), the entry, breakup, burst, crater, thermal and blast model used throughout the Impactor view. Note that equation 20 as typeset in the published PDF reads "34 + (l/H)²" where the derivation gives "3(4 + (l/H)²)"; with the corrected form this bench reproduces the paper's own Table 6 exactly. Collins, G. S. et al., MAPS 52:1542 (2017) for the airblast reassessment and the caution that the pancake model is calibrated by only two events.
• Boslough, M. (AMQUA 2010, Sandia SAND 2010-1280C) and Boslough, M. et al., "Arguments and Evidence Against a Younger Dryas Impact Event," AGU Geophysical Monograph 198:13-26 (2012): the largest impact expected in the past 20,000 years is about 250 m, and anything above 2 km carries a probability under 1%; a 4-km comet, even fragmenting on entry, "would generate a crater about 50 km in diameter"; fragments of a broken comet drift apart at tens of centimetres per second and so separate by much less than the object's own diameter before arrival; and a 10⁷-megaton explosion would have to detonate near 500 km to produce continental-scale blast, where the atmosphere is far too thin for anything to explode.
• Rasmussen, S. O. et al., JGR 111:D06102 (2006) and Quaternary Science Reviews 106:14 (2014) for the GICC05 chronology: GS-1 onset at 12,896 b2k (12,846 cal BP), ±4 yr relative and ±138 yr maximum counting error, termination at 11,703 b2k, duration 1,193 years. Steffensen, J. P. et al., Science 321:680 (2008): the deuterium-excess switch takes 1 to 3 years, the temperature response about 50. Cuffey, K. M. & Clow, G. D., JGR 102:26383 (1997), as smoothed in Alley, R. B., QSR 19:213 (2000), for the GISP2 accumulation rate of 0.086 m ice equivalent per year at 12.9 ka.
• Stratospheric residence times, the basis of the fifth requirement: Senel, C. B. et al., Nature Geoscience 16:1033 (2023) for fine silicate dust at one to two years with a tail to about fifteen; Bardeen, C. G. et al., PNAS 114:E7415 (2017) for soot at about six years under K-Pg loading; Robock, A., Reviews of Geophysics 38:191 (2000) and Toohey, M. et al., ACP 25:3821 (2025) for volcanic sulfate at roughly one to two years. Petaev et al. themselves noted their ~20-year platinum ingrowth "significantly exceeds the expected lifetime of about 5 years of fine dust".
• The non-impact alternatives: Condron, A. & Winsor, P., PNAS 109 (2012), Arctic meltwater routing weakening the Atlantic overturning circulation by more than 30% and being likelier than the St Lawrence route; Reinig, F. et al., "Precise date for the Laacher See eruption synchronizes the Younger Dryas," Nature 595:66-69 (2021), dating the eruption to 13,006 ± 9 cal BP and concluding the revised date precludes a direct link to Greenland Stadial-1 cooling; and Nana Yobo, L., Brandon, A. D., O'Brien, S., Halligan, J. J. & Waters, M. R., "Volcanic forcing of global climate cooling at the Younger Dryas onset preserved in North American sediments," Science Advances 12(18):eaec9030 (2026), reporting unradiogenic osmium with a volcanic-aerosol signature at Page-Ladson, Hall's Cave and Debra L. Friedkin, correlating with a cluster of bipolar eruptions at ~12.98 to 12.87 ka "whose cumulative radiative forcing exceeds the most volcanically active intervals of the Common Era".
• Impact flux: Brown, P. et al., Nature 420:294 (2002) and Brown, P. G. et al., Nature 503:238 (2013) for the bolide-derived rates at the small end; Harris, A. W. & Chodas, P. W., Icarus 365:114452 (2021) for the current survey-based recurrence estimates used by the bench. The unresolved factor-of-ten discrepancy between bolide counts and telescopic surveys in the 10 to 50 m range is disclosed on the instrument.