Bateubet

A stargazer's notebook of ink and watercolour. On every page a grid is split into tinted regions; each row, column and region needs the same number of stars, and no two stars may touch, even diagonally. Every page has one solution, and mistakes are circled in red like a teacher's mark. c. 150 The journey opens in Alexandria, where Ptolemy gathers older catalogues into the Almagest. Its four pages are small 5×5 and 6×6 grids, ideal for learning the inked star, the pencil dot and the eraser. 1420s Samarkand and Ulugh Beg's great meridian arc. Tools sit in round ink buttons below the grid: undo, dots, hint and erase. 1576 Uraniborg on the island of Hven, home of Tycho Brahe. Grids grow towards 8×8, and each finished chapter pastes a perforated stamp into your album. 1667 Paris and Cassini under the observatory dome. Each page can collect up to three marks, and every solved page closes with a wax seal pressed onto the sheet. 1675 Greenwich and the first Astronomer Royal. Away from the story, the five-minute night asks you to solve as many 6×6 skies as you can before dawn; a hint costs twenty seconds, and past nights are logged. 1839 Pulkovo and Struve's great refractor. The reading room holds a quiz on astronomers and observatories, ten questions a round from 24 real facts. 1917 Mount Wilson and the 100-inch Hooker telescope. Its 9×9 and 10×10 pages, like every grid of that size, ask for two stars in each line. 1970s Mauna Kea, above the clouds of Hawaii, closes the book with 10×10 pages: eight chapters, 32 puzzles, twelve stamps to collect. A brass astrolabe turns slowly behind the paper; switch Background animation off in Settings for a still page. Haptics and automatic dots can also be set there. Plays offline, with no account needed.