https://haccha-meccha.com/en/Data, math and science, checked with videos and hands-on experimentsenhttps://haccha-meccha.com/en/toukei/05/https://haccha-meccha.com/en/toukei/05/Wed, 28 Oct 2026 06:00:00 +0900The order keeps changing: we follow 8 countries from 1961 to 2025 and the top ten maker groups from 1999 as bars overtake each other. Country bars share one fi…https://haccha-meccha.com/en/scale/04/https://haccha-meccha.com/en/scale/04/Wed, 28 Oct 2026 05:00:00 +0900Fold a giant 0.1 mm sheet 42 times in a computer and compare its doubling thickness with a ruler, Earth and the Moon.https://haccha-meccha.com/en/meisaku/08/https://haccha-meccha.com/en/meisaku/08/Tue, 27 Oct 2026 06:00:00 +0900Natsume Sōseki's Kokoro in pictures: the young man, Sensei, his friend K, his wife Shizu, and the secret in Sensei's long letter.https://haccha-meccha.com/en/illusion/05/https://haccha-meccha.com/en/illusion/05/Tue, 27 Oct 2026 05:00:00 +0900The rings look as if they slide or rotate, but they are still images whose coordinates never change. It is apparent motion: the peripheral drift, Ouchi, and Pi…https://haccha-meccha.com/en/ricoflux/02/https://haccha-meccha.com/en/ricoflux/02/Mon, 26 Oct 2026 12:34:39 +0900RICOFLUX: a block breaker where you smash frozen glass with balls struck by your paddle, multiply them until they overflow, and break everything at once. Skies…https://haccha-meccha.com/en/ricoflux/01/https://haccha-meccha.com/en/ricoflux/01/Mon, 26 Oct 2026 12:34:39 +0900RICOFLUX: a block breaker where you smash cut glass with balls struck by your paddle, multiply them until they overflow, and break everything at once. Play on…https://haccha-meccha.com/en/moshimo/04/https://haccha-meccha.com/en/moshimo/04/Mon, 26 Oct 2026 09:00:00 +0900Yes — 10 of 10,000 dice-only test-takers passed the 20-question test (median of 3 simulation runs). By the binomial formula, about 1 in 1,100 people pass — 9.4…https://haccha-meccha.com/en/meisaku/06/https://haccha-meccha.com/en/meisaku/06/Mon, 26 Oct 2026 07:00:00 +0900Li Zheng, who has become a tiger, meets his old friend Yuan Can. He first asks Yuan Can to keep his poems, and only later asks him to care for his wife and chi…https://haccha-meccha.com/en/meisaku/07/https://haccha-meccha.com/en/meisaku/07/Mon, 26 Oct 2026 06:00:00 +0900On the night of the star festival, a boy named Giovanni rides a train across the Milky Way with his friend Campanella. The journey ends by a river, where Giova…https://haccha-meccha.com/en/oto/03/https://haccha-meccha.com/en/oto/03/Mon, 26 Oct 2026 05:00:00 +0900An empty forest window, where the light grows from blue pre-dawn into morning — an hour of birdsong and rustling leaves. The window brightens within ten minute…https://haccha-meccha.com/en/meisaku/05/https://haccha-meccha.com/en/meisaku/05/Sun, 25 Oct 2026 09:00:00 +0900From Paradise, the Buddha looks down on Kandata in Hell and lowers a spider’s thread. Kandata climbs up the thread toward Paradise, but the thread snaps and he…https://haccha-meccha.com/en/reverse/03/https://haccha-meccha.com/en/reverse/03/Sun, 25 Oct 2026 06:00:00 +0900The clear backing, cellophane, is made from the cellulose in wood pulp. Cellulose is dissolved into a solution, formed into film through a narrow slot in an ac…https://haccha-meccha.com/en/toukei/04/https://haccha-meccha.com/en/toukei/04/Sun, 25 Oct 2026 05:00:00 +0900In 1900, 17-year-olds averaged 157.9 cm (boys) and 147.0 cm (girls) — boys match today's 7th–8th graders, girls today's 6th graders. Height at 17 first peaked…https://haccha-meccha.com/en/meisaku/04/https://haccha-meccha.com/en/meisaku/04/Sat, 24 Oct 2026 09:00:00 +0900On his first day at a middle school in Shikoku, the hero of Natsume Soseki's Botchan hands out nicknames: Tanuki, Red Shirt, Porcupine. The story turns on what…https://haccha-meccha.com/en/chizu/03/https://haccha-meccha.com/en/chizu/03/Sat, 24 Oct 2026 06:00:00 +0900From the 1950s, water from the two rivers was diverted to irrigation; with no outlet to the ocean, evaporation kept pulling the level down. The former Aral Sea…https://haccha-meccha.com/en/illusion/04/https://haccha-meccha.com/en/illusion/04/Sat, 24 Oct 2026 05:00:00 +0900In the café wall, Zöllner, and Hering illusions, straight or parallel lines look tilted or bent. Sliding only the tiles, whitening the lines, or rotating the f…https://haccha-meccha.com/en/shikumi/03/https://haccha-meccha.com/en/shikumi/03/Fri, 23 Oct 2026 06:00:00 +0900The refrigerant carries heat out of the fridge interior and releases it into the room — that is why the back feels warm. It loops through the compressor, conde…https://haccha-meccha.com/en/meisaku/03/https://haccha-meccha.com/en/meisaku/03/Fri, 23 Oct 2026 05:00:00 +0900In a restaurant deep in the mountains, two gentlemen pass through seven doors of written orders in Kenji Miyazawa's tale. The turn comes when they finally catc…https://haccha-meccha.com/en/toukei/03/https://haccha-meccha.com/en/toukei/03/Thu, 22 Oct 2026 06:00:00 +0900No — in the opening comparison the 3DS ranks higher in Japan while the Wii ranks higher worldwide (manufacturer totals as of March 2016). This is not one conti…https://haccha-meccha.com/en/illusion/03/https://haccha-meccha.com/en/illusion/03/Thu, 22 Oct 2026 05:00:00 +0900Simultaneous contrast, the checker-shadow, and the Munker illusions make patches of one value look different. Covering the context or removing the stripes chan…https://haccha-meccha.com/en/scale/03/https://haccha-meccha.com/en/scale/03/Wed, 21 Oct 2026 06:00:00 +0900From a one-liter bottle to a pool, Lake Biwa, Lake Baikal, and all the water on Earth — everything becomes a ball at the same scale. "All Earth's water" follow…https://haccha-meccha.com/en/moshimo/03/https://haccha-meccha.com/en/moshimo/03/Wed, 21 Oct 2026 05:00:00 +0900Earth does move — but even with everyone gathered in one place, its center of mass shifts only about 2.6×10⁻¹⁴ m at the jump's peak. That is about one four-tho…https://haccha-meccha.com/en/shikumi/02/https://haccha-meccha.com/en/shikumi/02/Tue, 20 Oct 2026 06:00:00 +0900The step that vanishes at the top flips upside down, travels back beneath the floor, and comes out again at the bottom. A rail keeps each step level, so the st…https://haccha-meccha.com/en/illusion/02/https://haccha-meccha.com/en/illusion/02/Tue, 20 Oct 2026 05:00:00 +0900In the Ebbinghaus, Delboeuf, and Jastrow illusions, equal circles and strips look different in size. Removing the surrounds or overlaying copies changes the lo…https://haccha-meccha.com/en/meisaku/02/https://haccha-meccha.com/en/meisaku/02/Mon, 19 Oct 2026 09:00:00 +0900A servant with nowhere to go sits under a ruined gate in the rain, torn between starving and stealing. His heart turns at the moment he hears the old woman's l…https://haccha-meccha.com/en/toukei/02/https://haccha-meccha.com/en/toukei/02/Mon, 19 Oct 2026 08:00:00 +0900About 150 years ago Japan's population table listed 77 divisions; mergers and splits turned them into today's 47. Some prefectures that disappeared in the merg…https://haccha-meccha.com/en/oto/02/https://haccha-meccha.com/en/oto/02/Mon, 19 Oct 2026 07:00:00 +0900An open-air mountain room under the stars: one hour of campfire and night sounds, with no ceiling. A fire is struck, owls call twice, night wind returns, meteo…https://haccha-meccha.com/en/moshimo/02/https://haccha-meccha.com/en/moshimo/02/Mon, 19 Oct 2026 06:00:00 +0900The earlier you push, the smaller the speed needed to make the asteroid miss — though it depends on where it sits on its path. "Number of DARTs" assumes impact…https://haccha-meccha.com/en/hirameki/02/https://haccha-meccha.com/en/hirameki/02/Mon, 19 Oct 2026 05:00:00 +0900With 35 heads and 94 legs in the cage, there are 12 rabbits. This heads-and-legs puzzle comes from the Sunzi Suanjing, a Chinese math book written more than 1…https://haccha-meccha.com/en/scale/02/https://haccha-meccha.com/en/scale/02/Sun, 18 Oct 2026 07:00:00 +0900The Sun is far larger than any planet — yet some stars spread out beyond Jupiter's orbit. Of the 372 stars within about 32.6 light-years of the Sun, about 75%…