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Q & A: Double Shadows

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Most recent answer: 11/25/2018
Q:
is it possible to have two shadows yet one light source?
- cheryl (age 14)
p-town,VA,usa
A:
Cheryl -

Most shadows made by a single light source actually do have two parts, the . You can also get two separate shadows from one light source if you have two different objects to create them. But no, if you only have one light source and one object, you can't get more than one separate shadow.

-Tamara

ps. Ok, I guess if you took a long fluorescent light bulb and wrapped the center of it with black paper, then each end of the bulb would act like a single light source. Then the one bulb could create two separate shadows from just one object. But practically speaking, even though it's just one bulb, the two uncovered ends would really be two separate light sources.

(published on 10/22/2007)

Follow-Up #1: two shadows

Q:
I was noticing yesterday as i walked outside that i had two shadow's. it made me turn around to see who was behind me n there was no one there. I have heard that it means your going to die soon. I want the real answer please.
- miki (age 45)
Lakewood,Wa USA
A:
You get two shadows when the light is coming from two main sources, maybe two different street lamps.

Mike W.

(published on 08/27/2012)

Follow-Up #2: double shadow

Q:
When I was outside it was in the afternoon and i wasn't near any street lamps. So is this possible?
- miki (age 45)
Lakewood,Wa USA
A:
Could there have been reflections of the sun off some windows or metal surfaces?

Mike W.

(published on 08/28/2012)

Follow-Up #3: two shadows

Q:
No there wasn't anything around me, atleast nothing within 50 feet of me.
- miki (age 45)
Lakewood,Wa USA
A:
We're completely stumped.

Mike W.

(published on 08/30/2012)

Follow-Up #4: double shadows

Q:
This is a response to the question & answer about the "two shadows". At the end, you were stumped. On 7/30/13 I saw a double shadow of myself when I was coming out of my work building in the afternoon around 6:00 or 6:30pm. I have never seen this before. I looked behind me to see if there was a partial cloud close to the sun shining but it was just the sun shining brightly. The second shadow was faint to the left of me and my main shadow was to the right of me. But as I was walking out toward my car, it just faded more and more, very strange to see that. I checked again with the same conditions a couple days after and there was no 2nd shadow. I'm sure it was some atmospheric condition that caused this to happen like a light going through some kind of a prism (or water drop) where it splits off or something. Very phenominal.
- Laurie (age 60)
SLC UT, USA
A:

Maybe youre story will help some reader figure this out.

Mike W.


(published on 08/02/2013)

Follow-Up #5: Repeatability of Shadows

Q:
My friend and I were standing in a carpark at 9pm tonight and we noticed that we had 3 shadows each and couldn't believe what we were seeing. Other people were walking past us in the same spot and only had one shadow. our shadows were really big and noticeable and their shadows were small and narrow. My friend believes that it meant that our guides from the spirit world were around us.....could this be true if you believe?
- maddy (age 18)
penrith nsw australia
A:

Hi Maddy,

I'm sure the shadows were just some interesting geometry of the lights in the carpark and exactly where you and the passersby were standing... 

If I were you, I'd go back, and see if you can recreate the shadows! Assuming the lighting is the same as it was, you should be able to figure it out. :)

Cheers,

David Schmid


(published on 11/08/2013)

Follow-Up #6: Two shadows from a nightlight

Q:
In regards to dbl shadows - i was in my bathroom with a single light source, a small nightlight, and as i was leaving i noticed two shadows on the wall offset by about six inches and the one further away was darker. How can this be?
- Connie (age 39)
North Huntngdon, PA, USA
A:

Check out the other questions and answers on this topic--they might be interesting to you.

To get two shadows from one object, you need two light sources; either two real sources of light, or effectively two sources because of some kind of reflection. In this case, since you were in the bathroom, I wonder if there was a mirror nearby? The reflection of the nightlight from a mirror could act as a second light source, creating a second shadow. I would guess that the darker shadow just happened to be in a place where there was a little less background light, making it appear darker.

You can try to duplicate the effect under the same conditions to figure out exactly where the shadows were coming from.

Rebecca Holmes


(published on 09/11/2014)

Follow-Up #7: double shadows

Q:
Followup To the Double Shadow Conversation:Last night, I was leaving our church after being at Mass. It was a little after 6 PM but it was dark outside. I had two shadows! I had never ween that before and it really freaked me out. The one shadow was behind the other one and farther over to the right. I looked behind myself, at first, to see if someone was following me. Nobody was. It appeared that the shadow at the back might overtake me. I got to the car, where my husband was already sitting, and he reminded me that I had left his cushion in the church. So, I had to go back to get it. I got the cushion and, on the way back to the car, again encountered the double shadow phenomenon. I asked my husband if he'd ever had two shadows. He replied that, yes, he had and that it also freaked him out. He said it was caused by two light sources. He said that, if the lights show for far enough and long enough that the second shadow can even overtake the first. Is this possible? My guess is that, since it is a big church, there were lights on for the top story and also lights for the basement and they were shining outward. I have gone to this church on Saturday nights for years and this never happened before. Of course, it does get dark earlier now. I might never have gone to the car from that direction in the dark before.
- Linda Smallwood (age 69)
Moose Jaw, SK Canada
A:

Yes, just as your husband said, the two shadows come from two lights. The two shodows will pretty much overlap when the two lights are the same direction from you. As you walk, the shadow from the closer light will change its angle faster than the one from the farther light. So as you approach that overlap position, one shadow looks like it's ahead then as you pass the position the other one does.

Mike W. 


(published on 11/25/2018)

Follow-up on this answer.