3 ms·
Read every word. i liked this detail in the footnotes: > The Astro Compass needed to know approximately where in the sky to find the star, in order to point it
by pests 6mo ago
Read every word. i liked this detail in the footnotes:
> The Astro Compass needed to know approximately where in the sky to find the star, in order to point its sensor in the right direction. The direction didn't need to be exact because the Astro Compass performed a spiral search pattern to find the star. This search pattern covered ±4° in bearing and ±2.5° in altitude. In comparison, the Moon is 0.5° wide, so it's a fairly large target area. ↩
- DarenWatson 6mo agoHonestly that footnote really stood out to me too! the spiral search detail makes the whole system feel a lot more alive than I expected like it’s actively hunting for the star rather than just pointing and hoping.
- roeles 6mo agoThis is also used in laser communication systems to find your peer.
- nathanmcrae 6mo agoLaser trackers (used for metrology) can also use spiral search to find retroreflectors. Although I believe newer models generate a flash of infrared and find them via bright spots in the resulting image from a camera. I imagine modern celestial navigation systems evolved similarly (minus the infrared flash, not very useful for stars).