by johnnydeep » Thu Sep 21, 2023 3:31 pm
Chris Peterson wrote: ↑Thu Sep 21, 2023 3:00 pm
johnnydeep wrote: ↑Thu Sep 21, 2023 2:34 pm
alter-ego wrote: ↑Thu Sep 21, 2023 2:44 am
Ah, now I see what you were missing
![Idea :idea:](./images/smilies/icon_idea.gif)
. Yes, as the moon's limb progresses across the sun's limb, the mountain peaks pierce the sun's edge first forming the shadow peaks, and within seconds, as more of the mountains block light, less unblocked sunlight passes through the valleys and the shadows fatten until the all the lunar terrain blocks most, if not all of the light, and you then have the last ring in the sequences.
Edit: The chronology I described is for the exiting sequence (left side) - mountain peaks are first to form shadows. However, on the right side, valleys are the first to pass light, and the mountain peaks are last shadows. Obvious because the first ring on the right is mostly dark (little valley light), and the first ring on the left side (nearest maximum eclipse) are the point shadows (mountains).
Thanks. Still uncertain about something: per the text, the Moon moved in front of the Sun from left to right. That means the right limn Moon mountains started blocking the Sun first. Where is that first blockage - which would extend only a short way along the limn - shown in the APOD? Also, is the text implying that the shadows stretched out by the presentation of arcs here mimics the relative height of the Moon mountains?
Sorry, hate to be pedantic (okay, I don't hate it all that much). But it's "limb". Not "limn".
Pedantry is quite alright here, and you're right of course. I admit to being unsure about limn/limb when I wrote it (many times!), but failed to check. I'll use as my excuse the etymology of "limn", which has to do with light:
https://www.merriam-webster.com/dictionary/limn#did-you-know wrote:Allow us to shed some light on the history of limn, a word with lustrous origins. Limn traces to the Anglo-French verb aluminer and ultimately to the Latin illuminare, which means "to illuminate." Its use as an English verb dates from the days of Middle English; at first, limn referred to the action of illuminating (that is, decorating) medieval manuscripts with gold, silver, or brilliant colors. William Shakespeare extended the term to painting in his poem Venus and Adonis: "Look when a painter would surpass the life / In limning out a well-proportioned steed...."
So, you could say that during a lunar eclipse, the limb of the Moon is being limned - in shadow! - by the Sun, or that the limb of the Moon is delimning the Sun. Or something like that. Oh, and also, this APOD is limning the limb of the Moon! (Though is didn't do it brightly enough to limn my shadowed mind.) Ok, I'll stop now.
[quote="Chris Peterson" post_id=333932 time=1695308417 user_id=117706]
[quote=johnnydeep post_id=333930 time=1695306863 user_id=132061]
[quote=alter-ego post_id=333910 time=1695264254 user_id=125299]
Ah, now I see what you were missing :idea: . Yes, as the moon's limb progresses across the sun's limb, the mountain peaks pierce the sun's edge first forming the shadow peaks, and within seconds, as more of the mountains block light, less unblocked sunlight passes through the valleys and the shadows fatten until the all the lunar terrain blocks most, if not all of the light, and you then have the last ring in the sequences.
[i]Edit:[/i] The chronology I described is for the exiting sequence (left side) - mountain peaks are first to form shadows. However, on the right side, valleys are the first to pass light, and the mountain peaks are last shadows. Obvious because the first ring on the right is mostly dark (little valley light), and the first ring on the left side (nearest maximum eclipse) are the point shadows (mountains).
[/quote]
Thanks. Still uncertain about something: per the text, the Moon moved in front of the Sun from left to right. That means the right limn Moon mountains started blocking the Sun first. Where is that first blockage - which would extend only a short way along the limn - shown in the APOD? Also, is the text implying that the shadows stretched out by the presentation of arcs here mimics the relative height of the Moon mountains?
[/quote]
Sorry, hate to be pedantic (okay, I don't hate it all that much). But it's "limb". Not "limn".
[/quote]
Pedantry is quite alright here, and you're right of course. I admit to being unsure about limn/limb when I wrote it (many times!), but failed to check. I'll use as my excuse the etymology of "limn", which has to do with light:
[quote=https://www.merriam-webster.com/dictionary/limn#did-you-know]Allow us to shed some light on the history of limn, a word with lustrous origins. Limn traces to the Anglo-French verb aluminer and ultimately to the Latin illuminare, which means "to illuminate." Its use as an English verb dates from the days of Middle English; at first, limn referred to the action of illuminating (that is, decorating) medieval manuscripts with gold, silver, or brilliant colors. William Shakespeare extended the term to painting in his poem Venus and Adonis: "Look when a painter would surpass the life / In limning out a well-proportioned steed...."[/quote]
So, you could say that during a lunar eclipse, the limb of the Moon is being limned - in shadow! - by the Sun, or that the limb of the Moon is delimning the Sun. Or something like that. Oh, and also, this APOD is limning the limb of the Moon! (Though is didn't do it brightly enough to limn my shadowed mind.) Ok, I'll stop now.