Posting will likely be rather quiet for the next few weeks, as I’m taking another shot at National Novel Writing Month, aka NaNoWriMo! In the meantime, I’ll be keeping up my usual features, such as my editor’s selections and my twitter #weirdscifacts! The facts for the week are below the fold…
197. Sep 26: One of the first pioneers of the study of cryptanalysis (math of code-breaking) was Arab mathematician al-Kindi (807-873).
198. Sep 27: Lightning bolts have temperatures of 50,000 F, some 5 times hotter than the Sun’s surface.
199. Sep 28: c. 1926, Chadwick and Rutherford employed 3 young women as “scintillation counters”. To quote a bio of Chadwick, “it was thought that… they were less likely to be distracted by thinking while counting!” (The experiment ended up being biased because the women were always told the hoped-for results in advance.)
200. Sep 29: Archaea, the “forgotten” third domain of living things.
201. Sep 30: Physicist Struve worked as a lumberjack while a refugee from the Bolshevik revolution, and was almost struck by lightning. (The lightning bolt hit an adjacent tent, killing 6 people.)
202. Oct 01: Emperor Hirohito of Japan (1901-1989) was a biologist and a Fellow of the Royal Society.
203. Oct 02: The 1945 Trinity nuclear test got its name from Oppenheimer, who was inspired by the poetry of John Donne (1572-1631).
204. Oct 03: The wholphin, a cross-breed between a dolphin and a false killer whale. (FKW also a dolphin species, tho.)
204a. (via @nialldeacon) Pioneering geologist James Hutton had a doctorate of medicine from Leiden with a thesis on blood circulation. There are lots of early scientists whose formal training was in a completely different field than their major achievements!
205. Oct 04: The brother of crystallographer Kathleen Lonsdale was a wireless operator who received the last signals from Titanic in 1912. Another example of how connected many scientists were to the history of their time.
206. Oct 05: In 1975, J.H. Hetherington co-authored a physics paper with his cat, F.D.C. Willard! (h/t @tttabata via @sc_k!) (Read the cat story here; scroll down to “Cats and Publishing Physics Research”.)
207. Oct 06: Dating back to the 1600’s, thermometers were filled with Brandy instead of mercury. (h/t @anthinpractice) @ericmjohnson wryly noted: “But for some reason the levels kept going down, even when it wasn’t getting colder. ”
208. Oct 07: In 1990, father/son physicists R.S. Knox and W.H.Knox published an April 1 article with fictional authors Hoose and Zare.
208a. Follow-up to the previous fact, via @allinthegutter: “Physics can also boast Drs Lewney, Boffin & Nutter who were once in same dept, but sadly never published together.”
209. Oct 08: Bacteria can stand-up and walk! (h/t @davidmanly and @TanyaCNoel)
210. Oct 09: The gallium disappearing spoon trick; see the video here! Gallium melts at 85 degrees, and will vanish in a cup of tea — apparently this has been a long-standing practical joke amongst chemists at tea-time. h/t Sam Kean’s The Disappearing Spoon
hows the temperature of the sun measured? how is dat of a lightning bolt measured? hows it possibly 5 times of the sun for a lightning bolt?
hows the temperature of the sun measured?
With a very long ladder and a thermometer.
Good questions! The temperature of the Sun is measured, I believe, from its blackbody spectrum. An object that radiates light primarily through thermal radiation (like a very hot stove glows red) radiates over a well-defined range of colors that depends on its temperature. The Sun does not match this theoretical ideal, but is close enough to it to estimate its surface temperature based on the colors it radiates.
It’s a little less clear to me, doing a quick search, how the temperature of lightning is measured. One rough estimate comes from the observation that lightning can fuse silica into glass, which requires temperatures of some 30k degrees Celsius. When lightning hits sand, it can fuse the sand into a “petrified lightning bolt” known as a fulgurite (I have a piece of fulgurite in my office).
How is the temperature of lightning 5 times that of the Sun? Implicit in your question is the idea that the Sun represents the absolute highest temperature that an object can achieve, but the Sun’s temperature is based on its mass; other stars, for instance, are much hotter. To get something really hot, we just have to be able to pump a lot of thermal energy into it, and there’s not any in principle limit on how hot something can get!
how is the Sun’s temperature based on its mass? i thought the source of energy and heat in the sun was only the fusion process.
and, just wondering, what is the state of a lightning bolt?
“how is the Sun’s temperature based on its mass?”
Sorry about the delay in replying — crazy week! You are correct that the source of energy and heat in the sun is the fusion process. This fusion process, however, is driven by gravity crushing atoms together, and (roughly speaking) the more mass the star has, the higher the rate of fusion. More fusion = more temperature.