--- title: Olympiad: stars, light and space history ★★★ — a lesson of Mova's school · trees and pragmatics description: «Olympiad: stars, light and space history ★★★», a lesson of the space course of Mova's primary school, sentence by sentence with dependency trees and pragmatics. It begins: The second olympiad lesson leaves the planets for the stars, starlight and the people who explored space: each puzzle joins a d --- [Mova](https://md.mova.elamur.ai/free/en/) · [this page in HTML](https://mova.elamur.ai/free/en/corpora/school/space/32-olympiad-stars-light-and-space-history/) [home](https://md.mova.elamur.ai/free/en/) / [corpora](https://md.mova.elamur.ai/free/en/corpora/) / [school](https://md.mova.elamur.ai/free/en/corpora/school/) / [Space](https://md.mova.elamur.ai/free/en/corpora/school/space/) / Olympiad: stars, light and space histo… # Olympiad: stars, light and space history ★★★ Lesson 32 of the space course of Mova's primary school: 17 sentences, each with its syntax tree and pragmatics. The lessons are written for Mova, and their agreed trees are part of Mova corpus 0.4 (CC BY-SA 4.0). How Mova does on its tests: [the lesson at school](https://md.mova.elamur.ai/free/en/school-run/space/32-olympiad-stars-light-and-space-history/). - [0](https://md.mova.elamur.ai/free/en/corpora/school/space/32-olympiad-stars-light-and-space-history/0/) — The second olympiad lesson leaves the planets for the stars, starlight and the people who explored space: each puzzle joins a distance, a colour, a star's life or a date to another fact. - [1](https://md.mova.elamur.ai/free/en/corpora/school/space/32-olympiad-stars-light-and-space-history/1/) — The biggest trap is the light year: it is a distance, how far light goes in a year, so light from a star 4 light years away left it 4 years ago, and you see the star as it was then, not as it is now. - [2](https://md.mova.elamur.ai/free/en/corpora/school/space/32-olympiad-stars-light-and-space-history/2/) — A star's colour is a thermometer: red stars are the coolest, yellow ones like the Sun sit in the middle and blue-white ones are the hottest - the opposite of the red and blue taps on a sink. - [3](https://md.mova.elamur.ai/free/en/corpora/school/space/32-olympiad-stars-light-and-space-history/3/) — Picture Finn from Glasgow on a dreich night (dull and drizzly, in Scots), saying "That wee star's been up there a million years, ken" ("ken" means you know) - the million is hyperbole, but the real puzzle is how long its light has been travelling. - [4](https://md.mova.elamur.ai/free/en/corpora/school/space/32-olympiad-stars-light-and-space-history/4/) — Dates can be put in order like a story: the first rocket to reach space, the first satellite, the first animal in orbit, the first person, the first Moon landing and the space station that has never been empty since 2000. - [5](https://md.mova.elamur.ai/free/en/corpora/school/space/32-olympiad-stars-light-and-space-history/5/) — A light year is a distance, not a time: it is how far light travels in one year, about 9.5 trillion kilometres. - [6](https://md.mova.elamur.ai/free/en/corpora/school/space/32-olympiad-stars-light-and-space-history/6/) — Proxima Centauri is about 4.2 light years away, Sirius about 8.6, Vega about 25 and Polaris about 430, so their light left them that many years ago. - [7](https://md.mova.elamur.ai/free/en/corpora/school/space/32-olympiad-stars-light-and-space-history/7/) — Sunlight takes about 8 minutes 20 seconds to reach the Earth and moonlight about 1.3 seconds. - [8](https://md.mova.elamur.ai/free/en/corpora/school/space/32-olympiad-stars-light-and-space-history/8/) — Red stars are the coolest, about 3,000 degrees Celsius, the yellow-white Sun is about 5,500 degrees, and blue-white stars can be over 20,000 degrees. - [9](https://md.mova.elamur.ai/free/en/corpora/school/space/32-olympiad-stars-light-and-space-history/9/) — In Orion, Betelgeuse is a red star and Rigel is a blue-white star, so Rigel's surface is much hotter. - [10](https://md.mova.elamur.ai/free/en/corpora/school/space/32-olympiad-stars-light-and-space-history/10/) — A Sun-like star swells into a red giant, puffs off a planetary nebula and ends as a white dwarf about the size of the Earth. - [11](https://md.mova.elamur.ai/free/en/corpora/school/space/32-olympiad-stars-light-and-space-history/11/) — Stars more than about 8 times as heavy as the Sun end in a supernova and leave a neutron star, about 20 kilometres across, or a black hole. - [12](https://md.mova.elamur.ai/free/en/corpora/school/space/32-olympiad-stars-light-and-space-history/12/) — Stars twinkle because moving air bends their light; above the air, as on the International Space Station, they shine steadily. - [14](https://md.mova.elamur.ai/free/en/corpora/school/space/32-olympiad-stars-light-and-space-history/14/) — The Moon is moving away from the Earth by about 3.8 centimetres a year. - [16](https://md.mova.elamur.ai/free/en/corpora/school/space/32-olympiad-stars-light-and-space-history/16/) — Helium was found in the Sun's light in 1868, more than 25 years before it was found on the Earth, and its name comes from the Greek word for Sun. - [17](https://md.mova.elamur.ai/free/en/corpora/school/space/32-olympiad-stars-light-and-space-history/17/) — Around 240 BC Eratosthenes estimated the size of the Earth by comparing the Sun's shadows at two cities in Egypt. - [18](https://md.mova.elamur.ai/free/en/corpora/school/space/32-olympiad-stars-light-and-space-history/18/) — Even at Voyager's speed, a trip to Proxima Centauri would take about 75,000 years. - ← previous: [Olympiad: planet puzzles ★★★](https://md.mova.elamur.ai/free/en/corpora/school/space/31-olympiad-planet-puzzles/) - ↑ back to [Space](https://md.mova.elamur.ai/free/en/corpora/school/space/)