Search found 2 matches

by ommatidia
Mon Jan 29, 2024 10:28 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: The Pleiades: Seven Dusty Sisters (2024 Jan 29)
Replies: 23
Views: 5353

Re: APOD: The Pleiades: Seven Dusty Sisters (2024 Jan 29)

Chris, I would differ a bit and it might be a good project for a student. Visual acuity testing in ancient times, was crude with few accurate instruments. In many cultures, the predominant testing method was the recognition and identification of the constellations and celestial bodies of the night s...
by ommatidia
Mon Jan 29, 2024 9:08 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: The Pleiades: Seven Dusty Sisters (2024 Jan 29)
Replies: 23
Views: 5353

Re: APOD: The Pleiades: Seven Dusty Sisters (2024 Jan 29)

The Pleiades: In ancient times when we didn't understand visual acuity well, the Seven Sisters were regarded as a test of visual acuity. On a crystal clear night without competition from moonlight, if you could see all seven "sisters" you were considered to have normal or 20/20 vision. It ...