EAGER: A Test for the Younger Dryas Impact Hypothesis

该奖项在EARLY概念探索研究赠款（EAGER）计划的主持下提供资金，以调查在新仙女木（约12，900 - 11，500年前）开始时是否发生了火流星撞击，从而带来了巨大的气候变化。 研究小组计划通过测量Allerød-Younger Dryas边界上格陵兰冰盖项目2（GISP 2）冰芯中的铱浓度来实现这一科学目标。研究人员认为，与其他撞击研究一样，异常高的铱浓度是一个重大火流星撞击的指标，冰芯分析应该提供一个连续的，记录良好的，保存完好的地层序列，以寻找异常。 他们估计，由于陆地和宇宙尘埃的持续积累，目前假设强度的撞击将产生背景铱水平200至130，000倍的铱信号。因此，研究人员假设他们的分析将是对影响的决定性测试。这项研究可能会对更广泛的科学界产生广泛的影响，通过催化对现有科学理论的新的科学思考，即火流星撞击是新仙女木边界气候突变的一个原因。计划的活动非常适合EAGER计划的潜在变革，高风险和探索性质。

This award provides funds, under the auspices of the EArly-concept Grants for Exploratory Research (EAGER) program, to investigate whether a bolide impact occurred at the beginning of the Younger Dryas (approximately 12,900-11,500 years ago) thereby bringing about dramatic climatic change. The research team plans to accomplish this science goal by measuring iridium concentrations in the Greenland Ice Sheet Project Two (GISP2) ice core across the Allerød-Younger Dryas boundary. The researchers argue that, as with other impact studies, anomalously high iridium concentrations are an indicator of a major bolide impact and that the ice core analyses should provides a continuous, well-documented, and well-preserved stratigraphic sequence in which to search for an anomaly. They estimate that an impact of the currently hypothesized magnitude would have produced an iridium signal between 200 and 130,000 times the background iridium level due to the continuous accumulation of terrestrial and cosmic dust. As such, the researchers postulate that their analyses will be a definitive test of the impact. The research could have broad impact on the wider science community by catalyzing new scientific thinking about the existing scientific theory that a bolide impact was a contributory cause of abrupt climatic change at the Younger Dryas boundary.The planned activities fit well into the potentially transformative, high risk, and exploratory nature of the EAGER programs.