explainer Earth
How heavy is the Earth? About 5.97 × 10²⁴ kg, and how we know
Earth's mass is about 5.972 × 10²⁴ kg (13.2 septillion lb). See how scientists calculate it from orbits and G, why G limits precision, and the maths.
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Category: Earth
explainer Earth
How deep is the Grand Canyon? Depth, width and age
The Grand Canyon is about 1,524 m (5,000 ft) deep at the South Rim village and up to 1,829 m (6,000 ft) at its deepest, per the National Park Service.
news Anthropology Evidence status: Peer reviewed · Single-site archaeological geochemistry
Neolithic farmers in Greece faced no clear winter cold snap, limpet shells suggest
Oxygen isotopes in 121 limpet shells from Franchthi, Greece, show no clear winter cold snap as farming spread. One site, so the wider question stays open.
news Earth Evidence status: Peer reviewed · Rock-record dating study
End-Permian extinction hit North China’s land and sea in step, study says
River rocks date North China's end-Permian carbon upheaval to 252.1–252.0 Ma, in step with the marine die-off, but each age has a 220,000-year uncertainty.
explainer Earth
How cold is Everest? Summit and Base Camp temperatures by season
How cold is Everest? The summit averages about −35 °C in winter and −18 °C in July, by our station-based estimate. Base Camp, wind chill and why it is so…
news Earth Evidence status: Peer reviewed · Hindcast evaluation plus one real-time competition year
Machine learning doubles ECMWF’s AI subseasonal forecast skill, from a low base
Nature study: probabilistic bias correction doubles ECMWF's AI model's week 3 to 4 forecast skill, from 0.03 to about 0.06. What that does and does not mean.
news Earth Evidence status: Official announcement
Leap seconds end in May 2027 after vote to let UTC drift up to an hour
Metrology delegates voted on 15 October 2026 to end leap seconds: from 20 May 2027 UTC runs continuously and may drift up to 3,600 s from Earth time.
news Earth Evidence status: Peer reviewed · Palaeoclimate proxy data
Arctic winter sea ice may shrink more than models project, ancient clues suggest
Weighting 27 climate models by 6,000-year-old seabed sea ice clues suggests March Arctic ice may be nearly 1 million km² below the plain model average.
news Earth Evidence status: Peer reviewed · Statistical model of radiocarbon dates
Japan’s 7,300-year-old Kikai-Akahoya eruption hit Jomon foragers unevenly, study finds
A Science Advances model of 540 radiocarbon dates finds the Kikai-Akahoya eruption cut southern Kyushu's Jomon population while the north kept growing.