Apparent Size of Eberron's Moons [Archive] - Wizards Community

Apparent Size of Eberron's Moons [Archive] - Wizards Community

Post/Author/DateTime Post
Streamweaver
09-15-05, 03:27 PM One of my players and I have been having some discussions about how the moons would look to someone standing on Eberron and we can up with some values that surprised me.

Given the information about the moons from the Moons of Eberron Dragonshards it's fairly easy to figure how the apparent size a moon would have in the night sky. The equation is just Width(meters)/Distance(meters) * 57.3 = Apparent Size in Degrees of arch. For reference our own moon is about 0.51 degrees of arch when full. Here is the results we had for the moons as presented:

Moon - Apparent Angular Size (x size of our own moon)
Zarantyr - 5.008741259 (9.6)
Olarune - 2.419333333 (4.7)
Therendor - 1.616153846 (3.1)
Eyre - 1.322307692 (2.5)
Dravago - 1.478709677 (2.8)
Nymm - 0.542842105 (1.0)
Lharvion - 0.61884 (1.2)
Barrakas - 0.596875 (1.1)
Rhaan - 0.272857143 (0.5)
Sypheros - 0.35626943 (0.7)
Aryth - 0.259276018 (0.5)
Vult - 0.409285714 (0.8)

I really wasn't expecting these results, particularly not having many of the other moons being significantly larger than our own. It's quiet possible the moons could nearly blot out the night sky and cover most of it. I understand we don't know enough about luminosity to say how much light they cast off and the whole "it's magic" thing was tossed out relative to their orbits, but how big they would appear seems a fairly reasonable assumption. According to this they would seem huge in the night sky.

I've not been describing them that way in my campaign previously but it's an interesting result.
CravesLove
09-15-05, 04:01 PM Not questioning that, just curious:

Is it mentioned if these moons are the same distance from Eberron as our moon is from Earth?
Siran Dunmorgan
09-15-05, 04:15 PM It's been discussed before, right after the Moons dragonshard came out, and yes, the moons are huge.

The impression they're trying give is something like this:http://puvodni.startrek.cz/download/wall02.jpgat least with respect to Zarantyr.

—Siran Dunmorgan
Medesha
09-15-05, 04:59 PM Not questioning that, just curious:

Is it mentioned if these moons are the same distance from Eberron as our moon is from Earth?

Streamweaver's calculations use the distance the moons are from Eberron. Each moon is a different distance from the planet; not sure if any of them correspond to the distance of our moon from earth.

Moon Information (http://www.wizards.com/default.asp?x=dnd/ebds/20050307a)
ieattrollsforbreakfast
09-15-05, 05:05 PM This has come up before, and I made a few pictures to demonstrate the size of the moons. Lets see if I can find them...
http://www.geocities.com/ieattrollsforbreakfast/ebmoons.txt
http://www.geocities.com/ieattrollsforbreakfast/eberronday.txt
http://www.geocities.com/ieattrollsforbreakfast/zarantyr.txt
The first is the moons relative to our own, and the second is a shot of the sky during the day, though I forget which moons are shown. The third shows Zarantyr during a clear night.
CravesLove
09-15-05, 05:34 PM Streamweaver's calculations use the distance the moons are from Eberron. Each moon is a different distance from the planet; not sure if any of them correspond to the distance of our moon from earth.

Moon Information (http://www.wizards.com/default.asp?x=dnd/ebds/20050307a)

Cool, thanks Medesha :)

ieattrollsforbreakfast, I wasn't able to resolve those links. All I seemed to get was very dense garbled symbols?
Tek
09-15-05, 05:46 PM Try opening the links with Internet Explorer instead of Firefox. Otherwise, right click them and save them as JPG's. He named them .txt to get around the whole geocities thing.
Raster
09-15-05, 05:58 PM Beyond it (the Ring of Siberys), any of twelve moons, some full and bright, some only slivers and a few so far away as to appear to be stars, might be seen on any given evening.

Well I don't think being .8 x the size of our moon is small enough to look like a star (though I could be wrong), so I'm guessing that they just kind of threw the numbers out there without doing all the math (as seems to be the case with the population numbers) as a way to compare relative sizes and distances between the moons not between Eberron's moons and ours.
Medesha
09-15-05, 06:05 PM ieattrolls, those are seriously awesome! Thanks!
Streamweaver
09-15-05, 07:16 PM This has come up before, and I made a few pictures to demonstrate the size of the moons. Lets see if I can find them...
http://www.geocities.com/ieattrollsforbreakfast/ebmoons.txt
http://www.geocities.com/ieattrollsforbreakfast/eberronday.txt
http://www.geocities.com/ieattrollsforbreakfast/zarantyr.txt
The first is the moons relative to our own, and the second is a shot of the sky during the day, though I forget which moons are shown. The third shows Zarantyr during a clear night.

Okay I know I'm probably missing something obvious but those text files come across as garbled to me, thanks for pointing to them though.
Streamweaver
09-15-05, 07:18 PM Streamweaver's calculations use the distance the moons are from Eberron. Each moon is a different distance from the planet; not sure if any of them correspond to the distance of our moon from earth.

Moon Information (http://www.wizards.com/default.asp?x=dnd/ebds/20050307a)

Our own moon is abouit 250 thousand miles from the earth just for reference. However it's about 1/3rd the actual size of Earth itself which is extremely unusual as far as Astronomers know, there is some very interesting reading regarding how such a large moon many have formed, I wont go into it here but if you get a chance to look it up you'll probably enjoy what you read..
ieattrollsforbreakfast
09-15-05, 07:53 PM Since some people are having problems, I've uploaded the pictures in jpg format to the Bestiary instead. You shouldn't have problems viewing these:
http://www.eberronbestiary.com/ebmoons.JPG
http://www.eberronbestiary.com/eberronday.jpg
http://www.eberronbestiary.com/zarantyr.jpg
Tek
09-15-05, 08:18 PM Okay I know I'm probably missing something obvious but those text files come across as garbled to me, thanks for pointing to them though.

Try opening the links with Internet Explorer instead of Firefox. Otherwise, right click them and save them as JPG's. He named them .txt to get around the whole geocities thing.

Simply by reading my post you could have opened them fine.
Streamweaver
09-15-05, 08:21 PM Simply by reading my post you could have opened them fine.

Simply by not having an ego as big as Zarantyr you could have realized people don't hang on your every post.
CravesLove
09-15-05, 11:36 PM Try opening the links with Internet Explorer instead of Firefox. Otherwise, right click them and save them as JPG's. He named them .txt to get around the whole geocities thing.

Cool, that worked, thanks.

ieattrolls, very cool pic, thanks for helping us get a sense of what's happening.

Regards to you both,
Fitz
Streamweaver
09-16-05, 07:51 AM Since some people are having problems, I've uploaded the pictures in jpg format to the Bestiary instead. You shouldn't have problems viewing these:
http://www.eberronbestiary.com/ebmoons.JPG
http://www.eberronbestiary.com/eberronday.jpg
http://www.eberronbestiary.com/zarantyr.jpg

Those are really great, thanks for putting them together.

Post/Author/DateTime	Post
Streamweaver 09-15-05, 03:27 PM	One of my players and I have been having some discussions about how the moons would look to someone standing on Eberron and we can up with some values that surprised me. Given the information about the moons from the Moons of Eberron Dragonshards it's fairly easy to figure how the apparent size a moon would have in the night sky. The equation is just Width(meters)/Distance(meters) * 57.3 = Apparent Size in Degrees of arch. For reference our own moon is about 0.51 degrees of arch when full. Here is the results we had for the moons as presented: Moon - Apparent Angular Size (x size of our own moon) Zarantyr - 5.008741259 (9.6) Olarune - 2.419333333 (4.7) Therendor - 1.616153846 (3.1) Eyre - 1.322307692 (2.5) Dravago - 1.478709677 (2.8) Nymm - 0.542842105 (1.0) Lharvion - 0.61884 (1.2) Barrakas - 0.596875 (1.1) Rhaan - 0.272857143 (0.5) Sypheros - 0.35626943 (0.7) Aryth - 0.259276018 (0.5) Vult - 0.409285714 (0.8) I really wasn't expecting these results, particularly not having many of the other moons being significantly larger than our own. It's quiet possible the moons could nearly blot out the night sky and cover most of it. I understand we don't know enough about luminosity to say how much light they cast off and the whole "it's magic" thing was tossed out relative to their orbits, but how big they would appear seems a fairly reasonable assumption. According to this they would seem huge in the night sky. I've not been describing them that way in my campaign previously but it's an interesting result.
CravesLove 09-15-05, 04:01 PM	Not questioning that, just curious: Is it mentioned if these moons are the same distance from Eberron as our moon is from Earth?
Siran Dunmorgan 09-15-05, 04:15 PM	It's been discussed before, right after the Moons dragonshard came out, and yes, the moons are huge. The impression they're trying give is something like this:http://puvodni.startrek.cz/download/wall02.jpgat least with respect to Zarantyr. —Siran Dunmorgan
Medesha 09-15-05, 04:59 PM	Not questioning that, just curious: Is it mentioned if these moons are the same distance from Eberron as our moon is from Earth? Streamweaver's calculations use the distance the moons are from Eberron. Each moon is a different distance from the planet; not sure if any of them correspond to the distance of our moon from earth. Moon Information (http://www.wizards.com/default.asp?x=dnd/ebds/20050307a)
ieattrollsforbreakfast 09-15-05, 05:05 PM	This has come up before, and I made a few pictures to demonstrate the size of the moons. Lets see if I can find them... http://www.geocities.com/ieattrollsforbreakfast/ebmoons.txt http://www.geocities.com/ieattrollsforbreakfast/eberronday.txt http://www.geocities.com/ieattrollsforbreakfast/zarantyr.txt The first is the moons relative to our own, and the second is a shot of the sky during the day, though I forget which moons are shown. The third shows Zarantyr during a clear night.
CravesLove 09-15-05, 05:34 PM	Streamweaver's calculations use the distance the moons are from Eberron. Each moon is a different distance from the planet; not sure if any of them correspond to the distance of our moon from earth. Moon Information (http://www.wizards.com/default.asp?x=dnd/ebds/20050307a) Cool, thanks Medesha :) ieattrollsforbreakfast, I wasn't able to resolve those links. All I seemed to get was very dense garbled symbols?
Tek 09-15-05, 05:46 PM	Try opening the links with Internet Explorer instead of Firefox. Otherwise, right click them and save them as JPG's. He named them .txt to get around the whole geocities thing.
Raster 09-15-05, 05:58 PM	Beyond it (the Ring of Siberys), any of twelve moons, some full and bright, some only slivers and a few so far away as to appear to be stars, might be seen on any given evening. Well I don't think being .8 x the size of our moon is small enough to look like a star (though I could be wrong), so I'm guessing that they just kind of threw the numbers out there without doing all the math (as seems to be the case with the population numbers) as a way to compare relative sizes and distances between the moons not between Eberron's moons and ours.
Medesha 09-15-05, 06:05 PM	ieattrolls, those are seriously awesome! Thanks!
Streamweaver 09-15-05, 07:16 PM	This has come up before, and I made a few pictures to demonstrate the size of the moons. Lets see if I can find them... http://www.geocities.com/ieattrollsforbreakfast/ebmoons.txt http://www.geocities.com/ieattrollsforbreakfast/eberronday.txt http://www.geocities.com/ieattrollsforbreakfast/zarantyr.txt The first is the moons relative to our own, and the second is a shot of the sky during the day, though I forget which moons are shown. The third shows Zarantyr during a clear night. Okay I know I'm probably missing something obvious but those text files come across as garbled to me, thanks for pointing to them though.
Streamweaver 09-15-05, 07:18 PM	Streamweaver's calculations use the distance the moons are from Eberron. Each moon is a different distance from the planet; not sure if any of them correspond to the distance of our moon from earth. Moon Information (http://www.wizards.com/default.asp?x=dnd/ebds/20050307a) Our own moon is abouit 250 thousand miles from the earth just for reference. However it's about 1/3rd the actual size of Earth itself which is extremely unusual as far as Astronomers know, there is some very interesting reading regarding how such a large moon many have formed, I wont go into it here but if you get a chance to look it up you'll probably enjoy what you read..
ieattrollsforbreakfast 09-15-05, 07:53 PM	Since some people are having problems, I've uploaded the pictures in jpg format to the Bestiary instead. You shouldn't have problems viewing these: http://www.eberronbestiary.com/ebmoons.JPG http://www.eberronbestiary.com/eberronday.jpg http://www.eberronbestiary.com/zarantyr.jpg
Tek 09-15-05, 08:18 PM	Okay I know I'm probably missing something obvious but those text files come across as garbled to me, thanks for pointing to them though. Try opening the links with Internet Explorer instead of Firefox. Otherwise, right click them and save them as JPG's. He named them .txt to get around the whole geocities thing. Simply by reading my post you could have opened them fine.
Streamweaver 09-15-05, 08:21 PM	Simply by reading my post you could have opened them fine. Simply by not having an ego as big as Zarantyr you could have realized people don't hang on your every post.
CravesLove 09-15-05, 11:36 PM	Try opening the links with Internet Explorer instead of Firefox. Otherwise, right click them and save them as JPG's. He named them .txt to get around the whole geocities thing. Cool, that worked, thanks. ieattrolls, very cool pic, thanks for helping us get a sense of what's happening. Regards to you both, Fitz
Streamweaver 09-16-05, 07:51 AM	Since some people are having problems, I've uploaded the pictures in jpg format to the Bestiary instead. You shouldn't have problems viewing these: http://www.eberronbestiary.com/ebmoons.JPG http://www.eberronbestiary.com/eberronday.jpg http://www.eberronbestiary.com/zarantyr.jpg Those are really great, thanks for putting them together.