The largest young impact crater on Earth has been discovered. Located in South Korea, it measures 7 kilometers or 4 miles wide, and is carved deep into a highly mountainous area. Known as Hapcheon Crater, it formed a mere 42,300 years ago, and recent findings within its sediments revealed an interesting discovery. Specifically, involving stromatolites and early aerobic life forms. Thumbnail Photo Credit: Google Earth, Image © 2026 Airbus, Image © 2026 Maxar Technologies. This image was overlaid with text, and then overlaid with GeologyHub made graphics (the image border & the GeologyHub logo). Estimates on asteroid diameter, velocity, initial crater depth, tnt energy equivalent, and effects from the impact in this video were sourced using the calculator at https://impact.ese.ic.ac.uk/ImpactEarth/ImpactEffects/, which was used with permission. If you would like to support this channel, consider using one of the following links: (Patreon: http://patreon.com/geologyhub) (YouTube membership: https://www.youtube.com/channel/UCYeGh5VML5XPr5jYnzh3J6g/join) (Gemstone & Mineral Etsy store: http://prospectingarizona.etsy.com) (GeologyHub Merch Etsy store: http://geologyhub.etsy.com) Google Earth imagery used in this video: ©Google & Data Providers This video is protected under "fair use". If you see an image and/or video which is your own in this video, and/or think my discussion of a scientific paper (and/or discussion/mentioning of the data/information within a scientific paper) does not fall under the fair use doctrine, and wish for it to be censored or removed, contact me by email at [email protected] and I will make the necessary changes. Various licenses used in sections of this video (not the entire video, this video as a whole does not completely fall under one of these licenses) and/or in this video's thumbnail image (and this list does not include every license used in this video and/or thumbnail image): CC BY 2.0: https://creativecommons.org/licenses/by/2.0/legalcode CC BY 4.0: https://creativecommons.org/licenses/by/4.0/legalcode Sources/Citations: [1] Lim, J., Kim, Y., Park, S. et al. Discovery of stromatolite formation in post-impact hydrothermal lacustrine environments and its implications for early Earth. Commun Earth Environ 7, 334 (2026). https://doi.org/10.1038/s43247-026-03206-7, CC BY 4.0. This scientific paper was used as the source of information for the vast majority of this video. Including the impact crater age, stromatolite information, the hydrothermal lake age, duration, and presence of it and its hydrothermal system, and potential similarities to Archean oxygen production. [2] David C. Catling, Kevin J. Zahnle, The Archean atmosphere.Sci. Adv.6,eaax1420(2020).DOI:10.1126/sciadv.aax1420, CC BY 4.0. [3] Collins, Gareth & Lynch, Elliot & McAdam, Ronan & Davison, Thomas. (2017). A numerical assessment of simple airblast models of impact airbursts. Meteoritics & Planetary Science. 52. 10.1111/maps.12873., CC BY 4.0. 0:00 Hapcheon Crater 0:40 Impact Crater Comparison 2:09 Archean Earth 3:20 Aerobic Life 4:08 Impactor Details