Wikipedia:Reference desk/Archives/Science/2022 October 9

= October 9 =

Recent hunter's moon
Today Polish media announced a reddish hunter's moon with peak visibility across Poland on 9 October at 22:54 local time and other sources confirm the date. The visibility was clear, without clouds, and when I looked out at that time the full moon appeared ordinary with its pale yellow color and size. What went wrong? Brandmeistertalk  22:50, 9 October 2022 (UTC)


 * 22.54 would be far too late see an orange hunter's moon. You would need to observe it shortly after sunset. Shantavira|feed me 08:32, 10 October 2022 (UTC)


 * A red moon can appear during a lunar eclipse, which can only happen at full moon, but didn't happen at this full moon, or when the moon is very low in the sky. 22:54 local time was the exact moment of full moon, but that's not so important. It takes about 12 hours to clearly see the difference between a full moon and an almost full moon. To see a red moon, you'd have to look right after moonrise, the exact moment of which depends on your location. At full moon, moonrise is at about the same time as sunset.
 * There was nothing really special about this full moon. All full moons (except those with an eclipse) look about the same, the only difference being the position in the sky. The place in the sky where you can see the full moon is about the same as where you can see the sun half a year later. The variation in size is too small to notice with the unaided eye.
 * It happens quite often that the media tell about some special full moon that is in fact not really special. PiusImpavidus (talk) 08:56, 10 October 2022 (UTC)
 * It's been happening a lot more recently, dunno why. Farmers' Almanac and other such things have always listed the various names for the various moons, but for whatever reason they've become more popular to talk about in "gosh wow" media. Likewise "supermoons". --jpgordon&#x1d122;&#x1d106;&#x1D110;&#x1d107; 20:52, 10 October 2022 (UTC)
 * I agree, this modern fad for calling all full moons by some bizarre name which purports to come from some ancient tribal origins is absurd and misleading. I suggest the September full moon should be called the "Strictly Come Dancing Moon" because it occurs when that programme commences its season on the television. Yes, absurd isn't it, but no more absurd the the "Strawberry Moon" Richard Avery (talk) 14:24, 11 October 2022 (UTC)
 * I have noticed the same tendency on social media posts by people with a superficial interest in astronomy. They will trumpet very minor and repetitive fluctuations in moon phases or planetary alignments as a very big deal without any genuine evidence, and without presenting proper context, and applying dramatic names derived from folklore or pop culture to utterly routine astronomical events. Cullen328 (talk) 05:43, 11 October 2022 (UTC)
 * Our article supermoon introduces the word "micromoon."  That's a new one on me, and there's no indication of what the name means.   As to publicising the names of the lunar months, this may be related to some of them having been named ahead of the introduction of a common Easter date.   The month in which Orthodox Easter falls (which currently begins at earliest on 17 March and at latest on 14 April) is Miri, while the third month before that (the twelfth and last of the year) is Paul.   As the tropical year contains more than twelve lunar months, every second or third year Paul is followed by Paul II. -  2A00:23D0:511:4601:5CDB:1C06:42BD:A049 11:01, 11 October 2022 (UTC)
 * In general I agree with the foregoing, the press love a "gee whiz" story. However in the case of the harvest moon there appears to be a bit more to it than that.  The OED has the earliest recorded use of harvest moon in 1709 "Seventy Harvest-Moons Fill'd his wide Granaries with Autumnal Joy", so hardly a "modern fad".  The connection between the harvest moon and granaries is not co-incidental, when trying to get in the last of the corn an early, bright moon allowed a pre-industrial agrarian world to continue working.  You can't easily harvest by candles or torches and flames are a seriously bad idea in a field full of flamable grain. Martin of Sheffield (talk) 14:46, 11 October 2022 (UTC)
 * Of course the names aren't a "modern fad" -- making a fuss about them every month is the modern fad. --jpgordon&#x1d122;&#x1d106;&#x1D110;&#x1d107; 14:55, 11 October 2022 (UTC)
 * There was a trend in social media a few years ago when people would post something like "This year, October 13 falls on a Friday, making it the most evil day of the most evil month, an occurrence that only happens once every 856 years" or some bullshit like that. Even 5 seconds of thinking reveals that there's a Friday October 13th on average about every 7ish years or so, so most people will experience several in their lifetime, not once every millenium.  But people post things on Facebook because they think they might be interesting, not because they might be true.  It's the same with these moons.  Even the most unusual "moons" like blood moons or blue moons or "supermoons" happen every few years at the outside.  Even lunar eclipses happen about twice per year, so even accounting for the fact that they are only visible on part of the earth each time, most people will see one every few years or so.  -- Jayron 32 18:14, 11 October 2022 (UTC)
 * The version I've seen is "This year there are 5 Thursdays in October, something that only occurs once every 856 years". That such rank stupidity will be instantly believed and breathlessly re-shared is a terribly sad indictment on everyone involved. --  Jack of Oz   [pleasantries]  21:25, 11 October 2022 (UTC)
 * Discussed at Reference desk/Archives/Mathematics/2015 February 17. 88.111.188.163 (talk) 17:08, 12 October 2022 (UTC)
 * 800 years (ones the oldest millennial could remember if they die at 85 in bold):


 * 5 Thursdays in October: 1585, 1586, 1587, 1591, 1592, 1596, 1597, 1598, 1602, 1603, 1608, 1609, 1613, 1614, 1615, 1619, 1620, 1624, 1625, 1626, 1630, 1631, 1636, 1637, 1641, 1642, 1643, 1647, 1648, 1652, 1653, 1654, 1658, 1659, 1664, 1665, 1669, 1670, 1671, 1675, 1676, 1680, 1681, 1682, 1686, 1687, 1692, 1693, 1697, 1698, 1699, 1704, 1705, 1709, 1710, 1711, 1715, 1716, 1720, 1721, 1722, 1726, 1727, 1732, 1733, 1737, 1738, 1739, 1743, 1744, 1748, 1749, 1750, 1754, 1755, 1760, 1761, 1765, 1766, 1767, 1771, 1772, 1776, 1777, 1778, 1782, 1783, 1788, 1789, 1793, 1794, 1795, 1799, 1800, 1801, 1805, 1806, 1807, 1811, 1812, 1816, 1817, 1818, 1822, 1823, 1828, 1829, 1833, 1834, 1835, 1839, 1840, 1844, 1845, 1846, 1850, 1851, 1856, 1857, 1861, 1862, 1863, 1867, 1868, 1872, 1873, 1874, 1878, 1879, 1884, 1885, 1889, 1890, 1891, 1895, 1896, 1901, 1902, 1903, 1907, 1908, 1912, 1913, 1914, 1918, 1919, 1924, 1925, 1929, 1930, 1931, 1935, 1936, 1940, 1941, 1942, 1946, 1947, 1952, 1953, 1957, 1958, 1959, 1963, 1964, 1968, 1969, 1970, 1974, 1975, 1980, 1981, 1985, 1986, 1987, 1991, 1992, 1996, 1997, 1998, 2002, 2003, 2008, 2009, 2013, 2014, 2015, 2019, 2020, 2024, 2025, 2026, 2030, 2031, 2036, 2037, 2041, 2042, 2043, 2047, 2048, 2052, 2053, 2054, 2058, 2059, 2064, 2065, 2069, 2070, 2071, 2075, 2076, 2080, 2081, 2082, 2086, 2087, 2092, 2093, 2097, 2098, 2099, 2104, 2105, 2109, 2110, 2111, 2115, 2116, 2120, 2121, 2122, 2126, 2127, 2132, 2133, 2137, 2138, 2139, 2143, 2144, 2148, 2149, 2150, 2154, 2155, 2160, 2161, 2165, 2166, 2167, 2171, 2172, 2176, 2177, 2178, 2182, 2183, 2188, 2189, 2193, 2194, 2195, 2199, 2200, 2201, 2205, 2206, 2207, 2211, 2212, 2216, 2217, 2218, 2222, 2223, 2228, 2229, 2233, 2234, 2235, 2239, 2240, 2244, 2245, 2246, 2250, 2251, 2256, 2257, 2261, 2262, 2263, 2267, 2268, 2272, 2273, 2274, 2278, 2279, 2284, 2285, 2289, 2290, 2291, 2295, 2296, 2301, 2302, 2303, 2307, 2308, 2312, 2313, 2314, 2318, 2319, 2324, 2325, 2329, 2330, 2331, 2335, 2336, 2340, 2341, 2342, 2346, 2347, 2352, 2353, 2357, 2358, 2359, 2363, 2364, 2368, 2369, 2370, 2374, 2375, 2380, 2381


 * 5 Thursdays in February: 1596, 1624, 1652, 1680, 1720, 1748, 1776, 1816, 1844, 1872, 1912, 1940, 1968, 1996, 2024, 2052, 2080, 2120, 2148, 2176, 2216, 2244, 2272, 2312, 2340, 2368


 * Decade starting on Sunday: 1640, 1690, 1730, 1860, 1950, 2040, 2090, 2130, 2260, 2350


 * Latest possible Easter: 1666, 1734, 1886, 1943, 2038, 2190, 2258, 2326


 * Non-leap Olympic years: 1700, 1800, 1900, 2100, 2200, 2300


 * Earliest possible Easter: 1598, 1693, 1761, 1818, 2285, 2353


 * Leap centuries: 1600, 2000


 * Millenniums on Friday night or Saturday night: 2000. Once per 2,000 years.


 * Halloween blood moons (50 hours of Halloween worldwide): None. Next 2441 AD only time zones UTC+12 to 14.


 * That are also blue and hunters: All of them, it's guaranteed.


 * That your hometown can see on its actual Halloween night (dusk to midnight): About once per 4,000 years if clouds block half of these, a bit commoner where it's fall instead of spring.


 * That are also supermoons: >10 millenniums.


 * A total solar eclipse at the roof of your birthplace on your birthday: 260,000 years if clouds block half the events.


 * The chance of being born during a total solar eclipse: 2 minutes per 360 years. After accounting for clouds and non-emergency C-sections being delayed to see could be 1 per 200,000,000 births.


 * Century starting on Sunday: NEVER!!!!!!!


 * Even with 8 chances per cycle (1600, 1601, 1700, 1701, 1800, 1801, 1900 and 1901) Sunday is never used. No other weekday misses all 8 (Julian centuries starting Sunday: 400, 601, 1100, 1301, 1800) Sagittarian Milky Way (talk) 00:10, 13 October 2022 (UTC)


 * Point made, but with a couple of errors. Decades start on 1641 ... 2351; centuries start on 1601 ... 2001 and millennia on 2001 etc. Martin of Sheffield (talk) 08:09, 13 October 2022 (UTC)
 * The 165th decade starts 1641 but everyone uses 1640s instead. The 21st century and 3rd millennium are not the 2000s yet 2000 was a bigger party. Thanks a lot backwards Romans. India was probably already using the modern number system (didn't reach modern shape yet) by the Roman heyday which determined which backwards numerals the inventor of AD would use in 525 AD. There was one last chance to make at least the Anglosphere's millennium 2000 in the 74th decade as Bede popularized AD, he can fix it but alas Europe would continue using Roman numerals for general purposes for centuries more. Tacking on a year 0 to AD (but not BC as BC is a much newer invention) would also have the added benefits of being able to add 32.0 to 2022.0 if wondering how many years ago October 13th, 32 BC was, and bringing the birth of Jesus a little closer to December 25, 1 BC. As Jesus was born about 4-8 BC and in the summer. Sagittarian Milky Way (talk) 20:32, 13 October 2022 (UTC)
 * Why should every other decade suffer because decade 0 was defective, missing a year zero? Oh wait, we argued this to the ground around Y2K (or Y2K+1). --jpgordon&#x1d122;&#x1d106;&#x1D110;&#x1d107; 21:22, 13 October 2022 (UTC)

An odd couple of posts IMHO. Year numbers are not completed years like ages (but then again, consider that a 40 year old man in in his 41st year), but the year in which the event occurs. Something that occurred 6 months after the arbitrary start of AD was in the first year of AD, so June 1 AD. Something that happened 12 months previously was in the first year BC, so June 1 BC. Year 0 is a mathematician's erroneous dream, it is not a number line nor yet a missing year or a "defective decade". It simply cannot logically ever have existed, just as both Dionysius Exiguus and Bede wrote. Martin of Sheffield (talk) 21:45, 13 October 2022 (UTC)
 * B1950.0, J2000.0, 1900.0 1875.0, December 31.5 GMT, 2011.5 (on some star and "planet path this year" maps in paper books, the meridians move less than 0.014 degrees per year yet they still change the half year every year). Damn straight it should be extendable to a number line. If their numbers were like 3888.9 instead of MMMDCCCLXXXVIIIS····· (and 11/12ths) then year zero would probably exist. And maybe Jesus would rise Monday morning? (Saturday, Sunday, Monday — 3 days). In some American cities I think the addresses are the exact number of feet of latitude or longitude from something yet the streets can still have traditional names like 10th or Oak. So North 1st Street might be 1,000 feet north of Main and 1001W East 1st Avenue can't exist cause the center of the property would have to be 1 foot north of the center of 1st Street but a cop could write the body was at about N1001 E940. Or something like that. Two intersecting number lines far more precise than 1 block from just a street grid, now that's advanced! Sagittarian Milky Way (talk) 01:12, 14 October 2022 (UTC)