<p>It's a bunch of different phenomena, somewhat related, but still distinct.</p>

<p><strong>Naked eye</strong></p>

<p>Since you mention naked eye observations - seeing a small amount of short spikes around bright objects is normal. The causes can be multiple: diffraction of light in/around your eyelashes, dirt/secretions on the cornea, just regular aberrations in the eye's optical system, or in extreme cases it might actually signal vision problems.</p>

<p><strong>Your iPhone picture</strong></p>

<p>It appears that you're taking the picture through some fabric or some other kind of rectangular network-shaped material. In this case, the spikes are due simply to reflection of light on the individual threads. If you removed all fabric and kept only one thread without moving it at all, the light would reflect on it exactly in the same place.</p>

<p><strong>Telescopes</strong></p>

<p>Many reflector telescopes show a pattern of cross-shaped spikes around stars. Those are due to diffraction. Those telescopes have a secondary mirror supported by an X-shaped element called the "spider". Light is diffracting on the spider and creates a similar pattern of spikes around stars.</p>

CC BY-SA 3.0
2017-07-12T07:45:15.307Z
Hello, I am the OP. I believe I found the explanation for the phenomenon. I think what I saw was "light pillars". Florin Andrei's answer is the best.
user426132
CC BY-SA 3.0
2017-07-11T18:02:46.633Z
2017-07-11T18:02:46.633Z
Florin Andrei
<p>What's the name of the phenomenon when you look at a bright object (e.g. the moon) and see some perpendicular "beams" going top-down and right-left (bare eye observation, also slightly visible on iPhone pic)? </p>

<p><a href="https://ibb.co/j2b4AF" rel="nofollow noreferrer">https://ibb.co/j2b4AF</a>
see the link for a picture </p>

CC BY-SA 3.0
2017-07-10T12:15:42.960Z
Cataracts?  aperture diffraction?  too many mushrooms?
Carl Witthoft
CC BY-SA 3.0
2017-07-10T16:48:33.210Z
I am guessing that he/she is asking about diffraction spikes from the secondary support in reflector telescopes.
eshaya
CC BY-SA 3.0
2017-07-12T10:21:44.927Z
This appears to be a question about human biology, not astronomy
adrianmcmenamin
<amateur-observing><light>
Light distorsion/ilusion when looking at bright objects
klau
# Light distorsion/ilusion when looking at bright objects

(Asked by: username_0 on 2017-07-10)

What's the name of the phenomenon when you look at a bright object (e.g. the moon) and see some perpendicular "beams" going top-down and right-left (bare eye observation, also slightly visible on iPhone pic)?

<https://ibb.co/j2b4AF>
see the link for a picture

**Tags:** amateur-observing, light
> **Comments:**
> **username_1**: Cataracts?  aperture diffraction?  too many mushrooms?  
> **username_2**: I am guessing that he/she is asking about diffraction spikes from the secondary support in reflector telescopes.  
> **username_3**: This appears to be a question about human biology, not astronomy  

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## 1 answers

### Answer by username_4 on 2017-07-11. Score: 2

It's a bunch of different phenomena, somewhat related, but still distinct.

**Naked eye**

Since you mention naked eye observations - seeing a small amount of short spikes around bright objects is normal. The causes can be multiple: diffraction of light in/around your eyelashes, dirt/secretions on the cornea, just regular aberrations in the eye's optical system, or in extreme cases it might actually signal vision problems.

**Your iPhone picture**

It appears that you're taking the picture through some fabric or some other kind of rectangular network-shaped material. In this case, the spikes are due simply to reflection of light on the individual threads. If you removed all fabric and kept only one thread without moving it at all, the light would reflect on it exactly in the same place.

**Telescopes**

Many reflector telescopes show a pattern of cross-shaped spikes around stars. Those are due to diffraction. Those telescopes have a secondary mirror supported by an X-shaped element called the "spider". Light is diffracting on the spider and creates a similar pattern of spikes around stars.

> **Comments:**
> **username_5**: Hello, I am the OP. I believe I found the explanation for the phenomenon. I think what I saw was "light pillars". Florin Andrei's answer is the best.  

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