Serejka & Rurik
Rurik
I was digging through some old cartographer notes and found a sketch of a star chart that claims to guide a fleet straight to a lost island—no modern compasses, just celestial cues. Sounds like a neat puzzle for us; you’ll want the exact method, and I’ll hunt the story behind it. What do you think?
Serejka
Sure, I can look at the chart and see if the star positions line up. But without a reliable time source or a way to measure magnetic deviation, I’ll need you to give me the exact dates, the observer’s latitude, and any known errors in the sketch. Otherwise it’s just a guessing game. If you can pull that out of the notes, I’ll see what the puzzle really wants us to do.
Rurik
Alright, the map’s margin says it was drawn by a monk named Brother Alaric on March 12, 1472, when he was standing at 51°02′N, 0°03′E on the cliffs of Whitby. He noted the stars’ positions at local noon, so we need a sun‑position table for that date and location. The sketch itself is off by about 3.5° to the west for the star pair that marks the island’s compass. He also scribbled a margin: “Do not trust the north star’s spin, the iron in our era still twists.” That’s the magnetic error—roughly 5° westward bias for the compass we’d use today. Those should let us cross‑check the angles and pin the island’s spot. Let's get the tables and see if the stars line up.
Serejka
Sounds like we’re dealing with a couple of fixed offsets. First, grab the solar declination for March 12 – it’s about +7.5° N, so at 51° N the Sun’s altitude at noon would be roughly 90° – (51–7.5)=36.5°. That gives us a baseline for the “local noon” reference in the chart. Second, the star pair is 3.5° west of where it should be, so subtract that from whatever angular separation the monk recorded. Finally, the 5° magnetic west bias means we need to rotate the compass direction 5° east to compensate. Plug those numbers into the diagram, and you’ll get the corrected bearing to the island. If you run the numbers and it still doesn’t line up, we’ll know we’re missing something else.
Rurik
Great, got the numbers. Let’s pull the chart, apply the 3.5° west correction, then rotate the compass 5° east and see where the line lands. If it still misses, we’ll dig deeper—maybe a hidden error in the monk’s own measurements. Ready when you are.
Serejka
Alright, pull the chart, adjust the 3.5° west shift, then rotate the compass 5° east, and we’ll see the bearing. If it still misses, we’ll hunt the monk’s measurements for a hidden slip. Ready when you are.
Rurik
Got the chart. I’m shifting that star pair 3.5° to the west, then turning the compass reading 5° to the east. Hold tight – the bearing should line up now. If it still skews, we’ll double‑check Alaric’s notes for a hidden slip. Let's see where it points.