explainer Chemistry
How cold is dry ice? −78.5 °C, why it skips liquid, and safe handling
Dry ice is −78.5 °C (−109.3 °F, 194.7 K) at sea-level pressure. Why it sublimates, how it compares with liquid nitrogen, how long it lasts and safe handling.
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Category: Physics
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 Physics Evidence status: Peer reviewed · Lab demonstration
Google’s quantum chip cuts magic-state errors 40-fold, Science paper reports, but most attempts are discarded
Google's Willow chip cut magic-state errors about 40-fold in a Science paper, keeping only 8% of attempts. What cultivation is and what is still unproven.
news Physics Evidence status: Peer reviewed · Collider measurement
Jet quenching seen in RHIC oxygen collisions, a sign of quark–gluon plasma
STAR at Brookhaven's RHIC finds jets lose energy in oxygen–oxygen collisions, a sign of quark–gluon plasma at low energy. What was measured and its limits.
news Earth Evidence status: Peer reviewed · Laboratory shock experiments
Shocked magnesium oxide melts at 13,200 K, but its route depends on direction
Laser shocks put magnesium oxide's complete melting at 572 GPa and 13,200 K, and crystal direction changed when it transformed. What it means for planets.
explainer Astronomy
Why is the Moon orange tonight? Low Moons, smoke and eclipses explained
Why is the Moon orange tonight? Near the horizon its light crosses about 38 times more air, stripping out blue. See the maths, smoke's role and eclipse signs.
news Physics Evidence status: Peer reviewed · Accepted manuscript
Single-atom NMR: an STM tip drives one titanium nucleus, but how is unclear
Delft physicists ran NMR on one titanium-47 atom with an STM tip, resolving nuclear spin lines near 50 and 85 MHz. What they measured, and what is unknown.
explainer Astronomy
How hot is the Sun? Surface, core and corona temperatures
How hot is the Sun? The surface is 5,772 K (5,499 °C, 9,930 °F), the core about 15.7 million K and the corona 1 to 2 million K. See how…
explainer Physics
How far away is lightning? The flash-to-bang rule explained
Count seconds from flash to thunder and divide by 3 for km (5 for miles). Why it works, a worked example, and why any thunder means go indoors.