How dangerous are asteroid impacts to Earth?

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1. 1

   The Impact Hazard Assessment for Near-Earth Asteroid 2024 YR4.

   The journal of the astronautical sciences (Farnocchia et al.)Published Mar 5, 2026Checked Oct 4, 2026

   “Discovered by the ATLAS survey on December 27, 2024, asteroid 2024 YR4 represented one of the most significant impact risks ever detected. Roughly 60 m in size, this asteroid reached a 3% probability of impacting the Earth on December 22, 2032. We discuss the orbit and impact analyses carried by the three impact monitoring systems Sentry, Aegis, and NEODyS. The orbit solution proved to be remarkably stable and the impact probability behaved according to expectations as the uncertainty decreased thanks to additional observations, i.e., the impact probability initially increased as the Earth remained within the core of the uncertainty region and then dropped as the Earth moved towards the tail and eventually outside of the uncertainty region. Although the risk of an Earth impact has been ruled out, there remains a 4% probability of a lunar impact on December 22, 2032. To confirm or more likely rule out that possibility, we need to wait until new astrometric data become available, e.g., during the 2028 apparition.Supplementary informationThe online version contains supplementary material available at 10.1007/s40295-026-00576-0.”

2. 2

   The Hazardous NEOs of the Future: Long-term Predictions under Uncertainty.

   The journal of the astronautical sciences (Fuentes-Muñoz et al.)Published Jul 7, 2026Checked Oct 4, 2026

   “As the orbit is propagated into the future, the uncertainty in position grows faster than the uncertainty in the MOID. If the MOID is low but the position along the orbit is unknown, we compute an analytical approximation of the frequency of close encounters for a given distance. The NEO population spreads widely in orbital uncertainty, which we consider by propagating multiple samples from the initial orbital uncertainty distribution. We demonstrate and validate the methodology for 99942 Apophis, whose MOID is secularly increasing at a slow rate that still allows for future deep encounters. We apply this methodology to the NEO population, and for a large fraction we rule out the crossing of Earth's orbit in the next 1000 years. Otherwise, we rank NEOs in terms of how long their MOID will be low, long-term frequency of close encounters, and frequency relative to the background close encounter frequency for objects of similar size. These rankings identify NEOs that should be prioritized for future tracking and orbit refinement.”

3. 3

   Climatic and ecological responses to Bennu-type asteroid collisions.

   Science advances (Dai & Timmermann)Published Feb 5, 2025Checked Oct 4, 2026

   “There is an estimated chance of 0.037% that asteroid Bennu will collide with Earth in 2182 CE. The potential collision of such medium-sized asteroids can inject massive amounts of dust into the atmosphere, with unknown consequences for terrestrial and marine ecosystems. Here, we use the coupled high-top Community Earth System Model Version 2 with interactive chemistry to investigate how medium-sized asteroid strikes would affect climate, vegetation, and marine productivity. Our simulations, which inject up to 400 million tons of dust into the stratosphere, show marked disruptions in climate, atmospheric chemistry, and global photosynthesis. Global mean temperatures are projected to drop by 4°C, and global precipitation decreases by 15% in our simulations. The largest relative reductions in global terrestrial and marine net primary productivity reach 36 and 25%, respectively. Depending on the iron amount of the asteroid and the subsequent marine dust deposition, large diatom blooms occur in iron-limited regions such as the Southern Ocean and the eastern equatorial Pacific.”

4. 4

   No Place to Hide? Regional Resilience and Vulnerability to Global Catastrophic Risk.

   Global challenges (Hoboken, NJ) (Jehn et al.)Published Aug 23, 2026Checked Oct 4, 2026

   “This shows there is no place on Earth which is resilient against all kinds of GCR. Australia shows resilience across the widest range of GCR scenarios in the literature we reviewed, but even for it, continued international cooperation and trade are essential. Across the different risks, common resilience factors that show up most are geographic isolation (e.g. islands), self-sufficiency (especially in food production), high governance quality (more democratic and lower inequality) and decentralization to mitigate single point catastrophic failures (e.g. impacting trade or food supply). Many of these factors stand in tension with each other and trade-offs are required to balance between different GCR scenarios and between a higher resilience against the immediate impacts or against the longer-term consequences. The literature suggests that increased GCR resilience requires more investment in preparation (e.g., food security), planning (e.g., national risk assessments), and international agreements that facilitate cooperation on preparation and GCR response.”