Were there more than one recorder of astronomy; and how did the original?

Question

recorders know they were accurate so many years ago?

Answer 1

You mean recorders like Hipparchus, Tycho Brahe, Galileo, E.E. Barnard, and suitti?  No.  As an immortal, i'm all the same person.

Yeah, well before the invention of the telescope, i was limited to about 1 arc minute of accuracy.  That was determined by testing my eyesight with targets of known size at a known distance.  A little math gave the amount of error to expect.

Once the telescope was invented by my good friend Hans (i always called him Hans, or "Mr. L"), then there were constant issues with complicated things like focal lengths, apparent magnifications, imperfections in the lenses, and i just got tired of it and measured the error with targets of known size at a known distance.

But i didn't do the Hubble constant project.  Those bozos kept getting wildly wrong answers and reported error bars that were way too small - so they didn't even get results that matched within error bars.  Geez.  They could have just used targets of known sizes at known distances.

What was the question, again?  Speak up.  If you were my age, you'd be a little hard of hearing too!

Answer 2

Yes, many people made star maps of the sky.  How did they know they were accurate?  They were very careful, and other people checked their drawings.

The oldest star map we have is 32,500 years old.

Answer 3

I'm not familiar with that term.  Ephemerises were ancient lists of star locations.  People could check observations against the listed locations.