# Why aren't vampires affected by moonlight? **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [April 6, 2022, 10:36pm UTC](https://boards.straightdope.com/t/why-arent-vampires-affected-by-moonlight/962426 "2022-04-06T22:36:35Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Andy\_L](https://avatars.discourse-cdn.com/v4/letter/a/c67d28/32.png) [@Andy\_L](https://boards.straightdope.com/u/Andy_L)\ **Post date:** [April 7, 2022, 11:32am UTC](https://boards.straightdope.com/t/why-arent-vampires-affected-by-moonlight/962426/21 "2022-04-07T11:32:16Z")
The relationship of red shoes to vampiric light sensitivity is still poorly understood; more funding is required. ---
**Author:** ![Jasmine](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jasmine/32/2964_2.png) [@Jasmine](https://boards.straightdope.com/u/Jasmine)\ **Post date:** [April 7, 2022, 11:43am UTC](https://boards.straightdope.com/t/why-arent-vampires-affected-by-moonlight/962426/22 "2022-04-07T11:43:02Z")
For the same reason why moonlight doesn’t give you a tan. ---
**Author:** ![Alessan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/alessan/32/465_2.png) [@Alessan](https://boards.straightdope.com/u/Alessan)\ **Post date:** [April 7, 2022, 11:49am UTC](https://boards.straightdope.com/t/why-arent-vampires-affected-by-moonlight/962426/23 "2022-04-07T11:49:48Z")
IIRC, in Buffy it was _direct_ sunlight that hurt vampires - reflected sunlight didn’t do anything to them, although it did make them nervous. They could safety stand in front of an open window at noon, so long as it was facing north. ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [April 7, 2022, 1:02pm UTC](https://boards.straightdope.com/t/why-arent-vampires-affected-by-moonlight/962426/24 "2022-04-07T13:02:06Z")
The rules affecting vampires are whatever the writer makes up at the time. This has been the case ever since Polidori’s _The Vampyre_, and especially since Bram Stoker, who himself not only invented many of the “rules” of vampires, but even the idea that there was a set of rules governing their behavior. Before him there were few defined circumstances to their existence (creatures of the night, driving a stake through the heart to kill them – not invariable, but used in _Varney_ and _Carmilla_) Ever since then, we’ve been subjected to a long list of “rules” about the ways of vampires, with a central group of accepted “facts” and subsidiary rules that change from author/filmmaker to author/filmmaker. As for vampires dissolving in sunlight, as I’ve remarked in an article, a book, on my website, and many times on this Board, it’s a creation of the movies. It was first used in Murnau’s _Nosferatu_, but it would have never caught on had not two film studios used the idea first in 1943 and a third studio in 1958. But people started thinking about the fact that vampires apparently don’t suffer under artificial light – candles and incandescents, and when the government started pushing the idea of sunblock and SPF the idea clicked that maybe it was _ultraviolet_ light that was killing vampires. (I’;m sure no one thought it out this carefully, but it’s true that both candle light and incandescent light have much less UV than natural sunlight) And so one answer to the OP’s question is that moonlight does, indeed, not have as much UV as sunlight does, so maybe that’s why it doesn’t hurt vampires > **[Sunlight](https://en.wikipedia.org/wiki/Sunlight)** > > Pages for logged out editors learn more > > Sunlight is a portion of the electromagnetic radiation given off by the Sun, in particular infrared, visible, and ultraviolet light. On Earth, sunlight is scattered and filtered through Earth's atmosphere, and is obvious as daylight when the Sun is above the horizon. When direct solar radiation is not blocked by clouds, it is experienced as sunshine, a combination of bright light and radiant heat. When blocked by clouds or reflected off other obje... > **[Aquarium Lighting: Moonlight – A Concise Review of Its Spectrum, Intensity,...](https://reefs.com/magazine/aquarium-lighting-moonlight-a-concise-review-of-its-spectrum-intensity-photoperiod-and-relationship-to-coral-and-fish-spawning/)** > > Moonlight is thought to play an important role in timing reproductive cycles of many coral and fish species. In corals, lunar cycles set the date of spawning, while the time of onset of darkness fine tunes the cycle and decide the hour and minute... I’m sure it has nothing at all to do with the demands of the story, or of the need for spooky atmosphere. Incidentally, the idea that vampires could function perfectly well if they wore sunblock with a sufficiently high SPF was being kicked around by the 1970s, although the first case of it being used in a story that I can recall is HBO’s **Tales from the Crypt: Bordello of Blood** (1996) Here’s my webpage on Vampires and Sunlight – [Vampires — Keep Out of Direct Sunlight – The Writings of Stephen R. Wilk](https://srichardwilkcom.wordpress.com/vampires-keep-out-of-direct-sunlight/) ---
**Author:** ![Darren\_Garrison](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darren_garrison/32/92_2.png) [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)\ **Post date:** [April 7, 2022, 1:46pm UTC](https://boards.straightdope.com/t/why-arent-vampires-affected-by-moonlight/962426/25 "2022-04-07T13:46:51Z")
> [@Alessan](#): > > IIRC, in Buffy it was _direct_ sunlight that hurt vampires - reflected sunlight didn’t do anything to them, although it did make them nervous. The amount of sunlight needed to harm a vampire varied enormously depending on what that episode’s plot needed. ---
**Author:** ![LivingGhost371](https://avatars.discourse-cdn.com/v4/letter/l/b9e5f3/32.png) [@LivingGhost371](https://boards.straightdope.com/u/LivingGhost371)\ **Post date:** [April 7, 2022, 4:53pm UTC](https://boards.straightdope.com/t/why-arent-vampires-affected-by-moonlight/962426/26 "2022-04-07T16:53:02Z")
Sometime yes, sometimes no. Really basic cameras like you might attach to your VCR at home, or later were found in consumer camcorders, would use a single pickup tube, so no mirrors needed. Really expensive studio type cameras would use triple tubes, and use a prism to split the light into it’s red, green, and blue components. The problem is that the (long) tubes had to be mounted at angles to each other, meaning the result was incredible bulky, and making it cheap and portable was out of the question. In the middle you had cheaper studio cameras and portable cameras that did indeed use mirrors (completely reflective as well as beam splitters); this allowed the tubes to be mounted parallel to each other making it smaller and cheaper. The drawback is that there had to be slop built into the system to allow for thermal expansion and contraction, meaning that it had to be adjustable, meaning it could pop out of adjustment. In practice you made vertical, horizontal, and rotational adjustments to the signal using electronic pots to compensate for physical differences of the tubes, for both the red and blue tubes. If the camera got bumped or sometimes just because, this could pop out of alignment in the middle of a shoot. However, the green component of the light went straight through to the green tube without being reflected by a mirror. New CCD cameras with multiple sensors also use prisms. Therefore, unless there’s some property of a Vampire that also prevents the image from being transmitted straight through a beam splitter, I’d expect any kind of video camera would be able to record a vampire. Albeit they’d appear green if recorded by a three tube mirror relay camera. ---
**Author:** ![Love\_Rhombus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/love_rhombus/32/10694_2.png) [@Love\_Rhombus](https://boards.straightdope.com/u/Love_Rhombus)\ **Post date:** [April 7, 2022, 7:14pm UTC](https://boards.straightdope.com/t/why-arent-vampires-affected-by-moonlight/962426/27 "2022-04-07T19:14:10Z")
> [@LivingGhost371](#): > > I’d expect any kind of video camera would be able to record a vampire. There was a British miniseries called Ultraviolet which featured vampires who couldn’t be seen this way-thusly all guns had a camera attached to tell the vamps from humans. ---
**Author:** ![Left\_Hand\_of\_Dorkness](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/left_hand_of_dorkness/32/7156_2.png) [@Left\_Hand\_of\_Dorkness](https://boards.straightdope.com/u/Left_Hand_of_Dorkness)\ **Post date:** [April 7, 2022, 7:23pm UTC](https://boards.straightdope.com/t/why-arent-vampires-affected-by-moonlight/962426/28 "2022-04-07T19:23:48Z")
A related question: when did scientists/scholars/philosophers realize that the moon’s light was reflected sunlight? Edit: [woah, this is cool](https://history.stackexchange.com/questions/7890/who-discovered-first-that-the-moon-does-not-have-its-own-light#:~:text=Anaxagoras%20proposed%20that%20the%20moon,of%20the%20sun%20and%20moon.) > [@](#): > > Anaxagoras [[(500 BCE–428 BCE)](http://en.wikipedia.org/wiki/Anaxagoras)] brought philosophy and the spirit of scientific inquiry from Ionia to Athens. His observations of the celestial bodies and the fall of meteorites led him to form new theories of the universal order. He attempted to give a scientific account of eclipses, meteors, rainbows, and the sun, which he described as a mass of blazing metal, larger than the Peloponnese. **He was the first to explain that the moon shines due to reflected light from the sun.** > … > In about 450 BC Anaxagoras was imprisoned for claiming that the Sun was not a god and that the Moon reflected the Sun’s light. ---
**Author:** ![Richard\_Pearse](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/richard_pearse/32/13144_2.png) [@Richard\_Pearse](https://boards.straightdope.com/u/Richard_Pearse)\ **Post date:** [April 7, 2022, 8:08pm UTC](https://boards.straightdope.com/t/why-arent-vampires-affected-by-moonlight/962426/29 "2022-04-07T20:08:14Z")
> [@Jasmine](#): > > For the same reason why moonlight doesn’t give you a tan. Yes, exactly! ---
**Author:** ![N9IWP](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/n9iwp/32/3154_2.png) [@N9IWP](https://boards.straightdope.com/u/N9IWP)\ **Post date:** [April 7, 2022, 9:03pm UTC](https://boards.straightdope.com/t/why-arent-vampires-affected-by-moonlight/962426/30 "2022-04-07T21:03:18Z")
A very small amount of UV is reflected by the moon. The UV albedo at 2400A is about 10% of the visual light albedo: [https://adsabs.harvard.edu/full/1974Moon....9..295C](https://adsabs.harvard.edu/full/1974Moon....9..295C) Brian ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [April 7, 2022, 9:30pm UTC](https://boards.straightdope.com/t/why-arent-vampires-affected-by-moonlight/962426/31 "2022-04-07T21:30:55Z")
> [@CalMeacham](#): > > Incidentally, the idea that vampires could function perfectly well if they wore sunblock with a sufficiently high SPF was being kicked around by the 1970s, although the first case of it being used in a story that I can recall is HBO’s **Tales from the Crypt: Bordello of Blood** (1996) Not a vampire, but the Discworld books include trolls, which are also harmed by sunlight (though not lethally-- It just makes them comatose until sunset). And they’re using sunblock to go out by day anyway, at least by Men At Arms (1993), and I think by Moving Pictures (1990). ---
**Author:** ![Lucas\_Jackson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lucas_jackson/32/303_2.png) [@Lucas\_Jackson](https://boards.straightdope.com/u/Lucas_Jackson)\ **Post date:** [April 7, 2022, 10:22pm UTC](https://boards.straightdope.com/t/why-arent-vampires-affected-by-moonlight/962426/32 "2022-04-07T22:22:48Z")
> [@Left\_Hand\_of\_Dorkness](#): > > In about 450 BC Anaxagoras was imprisoned for claiming that the Sun was not a god You would have thought the good townsfolk would have let the Deity take care of that little chore Himself. They must not have had a lot of faith in Sun, the God. ---
**Author:** ![Left\_Hand\_of\_Dorkness](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/left_hand_of_dorkness/32/7156_2.png) [@Left\_Hand\_of\_Dorkness](https://boards.straightdope.com/u/Left_Hand_of_Dorkness)\ **Post date:** [April 7, 2022, 11:19pm UTC](https://boards.straightdope.com/t/why-arent-vampires-affected-by-moonlight/962426/33 "2022-04-07T23:19:33Z")
> [@Lucas\_Jackson](#): > > You would have thought the good townsfolk would have let the Deity take care of that little chore Himself. They must not have had a lot of faith in Sun, the God. You know what they say, God helps those that help imprison the infidels. ---
**Author:** ![lobotomyboy63](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lobotomyboy63/32/2900_2.png) [@lobotomyboy63](https://boards.straightdope.com/u/lobotomyboy63)\ **Post date:** [April 7, 2022, 11:51pm UTC](https://boards.straightdope.com/t/why-arent-vampires-affected-by-moonlight/962426/34 "2022-04-07T23:51:55Z")
The color temperature of moonlight is 4100K, and Daylight with Clear Sky (sun overhead) is 5000-6500K. Maybe that’s it. ---
**Author:** ![Dr\_Paprika](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr_paprika/32/3042_2.png) [@Dr\_Paprika](https://boards.straightdope.com/u/Dr_Paprika)\ **Post date:** [April 12, 2022, 10:35pm UTC](https://boards.straightdope.com/t/why-arent-vampires-affected-by-moonlight/962426/35 "2022-04-12T22:35:22Z")
What are the vampire legends in places that have a lot of sunlight? I’m thinking very long summer days like Northern Scandinavia. But it could also mean a tropical place with more hotter days so more intense sun - are there fewer vampires in Ecuador or the Australian Gold Coast? ---
**Author:** ![Alessan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/alessan/32/465_2.png) [@Alessan](https://boards.straightdope.com/u/Alessan)\ **Post date:** [April 12, 2022, 10:50pm UTC](https://boards.straightdope.com/t/why-arent-vampires-affected-by-moonlight/962426/36 "2022-04-12T22:50:53Z")
The closest thing to a vampire in Middle Eastern folklore is the [ghoul](https://en.wikipedia.org/wiki/Ghoul), and while some versions do prefer to lurk about and eat people at night, I don’t think they’re particularly vulnerable to sunlight. ---
**Author:** ![Lucas\_Jackson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lucas_jackson/32/303_2.png) [@Lucas\_Jackson](https://boards.straightdope.com/u/Lucas_Jackson)\ **Post date:** [April 12, 2022, 11:38pm UTC](https://boards.straightdope.com/t/why-arent-vampires-affected-by-moonlight/962426/37 "2022-04-12T23:38:31Z")
> [@Left\_Hand\_of\_Dorkness](#): > > God helps those that help imprison the infidels. I need that Tshirt. ---
**Author:** ![Toxylon](https://avatars.discourse-cdn.com/v4/letter/t/f05b48/32.png) [@Toxylon](https://boards.straightdope.com/u/Toxylon)\ **Post date:** [April 14, 2022, 1:31pm UTC](https://boards.straightdope.com/t/why-arent-vampires-affected-by-moonlight/962426/38 "2022-04-14T13:31:12Z")
> [@Dr\_Paprika](#): > > What are the vampire legends in places that have a lot of sunlight? I’m thinking very long summer days like Northern Scandinavia. AFAIK, there are no vampire legends from there. They are a late Eastern European import. ---
**Author:** ![burpo\_the\_wonder\_mutt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/burpo_the_wonder_mutt/32/365_2.png) [@burpo\_the\_wonder\_mutt](https://boards.straightdope.com/u/burpo_the_wonder_mutt)\ **Post date:** [April 14, 2022, 5:27pm UTC](https://boards.straightdope.com/t/why-arent-vampires-affected-by-moonlight/962426/39 "2022-04-14T17:27:20Z")
Renegade theory I just made up: vampires are weakened by Solar Wind. They can move around in the daytime (Stoker’s “Dracula”) but in a depleted state. At night, no SW, they’re all powerful. The moon doesn’t reflect enough SW to affect them. This accounts for _Lifeforce_’s Naked-Lady-Vampire, who has to constantly sleep in the spacecraft because of the pervasiveness of SW in Open Space. Whatta ya think, sirs? (Ignore him, he’s raving – mrs. burpo) ---
**Author:** ![Miller](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/miller/32/481_2.png) [@Miller](https://boards.straightdope.com/u/Miller)\ **Post date:** [April 14, 2022, 6:48pm UTC](https://boards.straightdope.com/t/why-arent-vampires-affected-by-moonlight/962426/40 "2022-04-14T18:48:34Z")
> [@Dr\_Paprika](#): > > What are the vampire legends in places that have a lot of sunlight? I’m thinking very long summer days like Northern Scandinavia. Yeah, but you also got those really long nights in the winter. There’s a 2007 movie, _Thirty Days of Night_, about a bunch of vampires that take over an Alaskan town that goes a full month of no sun in the winter. [Previous page](https://boards.straightdope.com/t/why-arent-vampires-affected-by-moonlight/962426.md?page=1) [Next page](https://boards.straightdope.com/t/why-arent-vampires-affected-by-moonlight/962426.md?page=3)