<p>What you saw was a <a href="http://www.atoptics.co.uk/atoptics/ray1.htm" rel="nofollow">crepuscular ray</a>. They occur when the Sun's rays stream through gaps in clouds. Such rays tend to appear as parallel columns.</p>

<p>If you look closely at the picture you took, there is a subtle angled crepuscular column above the short building near the middle of the picture.</p>

CC BY-SA 3.0
2015-09-23T11:33:55.377Z
Maybe 'parallel' is not quite the right word here, since they *appear* to radiate. Also: Any possibility it was [a sun pillar](https://en.wikipedia.org/wiki/Light_pillar)? Seems like maybe those only form in cold weather.
Matt Hall
CC BY-SA 3.0
2015-09-23T11:47:26.857Z
How cold was the air over Boston when the picture was taken?
Fred
CC BY-SA 3.0
2015-09-23T13:20:50.333Z
It was definitely **not** a crepuscular ray, the edges of which could not appear parallel unless observed from an angle near the sun, I think. We were thinking it could be something like a sun pillar--I didn't know that was the term, but the same thing happens on water when there are small ripples.
John Hughes
CC BY-SA 3.0
2015-09-24T13:00:52.327Z
Altohugh I'd given Fred an up-tick, I think I agree. Crepescular rays are quite common (I saw some brilliant ones a few minutes ago here in TX) and as you say they never appear parallel.
winwaed
CC BY-SA 3.0
2015-09-23T07:44:01.800Z
2015-09-23T07:44:01.800Z
Fred
<p>This evening in Boston there was quite a spectacular sunset. However, many people noticed this odd vertical "stripe" in the west. </p>

<p>Has anyone seen this before? </p>

<p>It <em>looked</em> as though it was projected on the clouds from somewhere near where I was standing (as though a reflection of the sun). This would make sense (the city of Boston, with it's tall glass towers, was right next to us), but could the reflection really reach so far and be described so clearly on the clouds? </p>

<p><a href="https://i.sstatic.net/NDerE.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/NDerE.jpg" alt="enter image description here"></a></p>

<meteorology><clouds>
Unusual light at sunset?
John Hughes
# Unusual light at sunset?

(Asked by: username_0 on 2015-09-23)

This evening in Boston there was quite a spectacular sunset. However, many people noticed this odd vertical "stripe" in the west.

Has anyone seen this before?

It *looked* as though it was projected on the clouds from somewhere near where I was standing (as though a reflection of the sun). This would make sense (the city of Boston, with it's tall glass towers, was right next to us), but could the reflection really reach so far and be described so clearly on the clouds?

[![enter image description here](https://i.sstatic.net/NDerE.jpg)](https://i.sstatic.net/NDerE.jpg)

**Tags:** meteorology, clouds


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## 1 answers

### Answer by username_1 on 2015-09-23. Score: 3

What you saw was a [crepuscular ray](http://www.atoptics.co.uk/atoptics/ray1.htm). They occur when the Sun's rays stream through gaps in clouds. Such rays tend to appear as parallel columns.

If you look closely at the picture you took, there is a subtle angled crepuscular column above the short building near the middle of the picture.

> **Comments:**
> **username_2**: Maybe 'parallel' is not quite the right word here, since they *appear* to radiate. Also: Any possibility it was [a sun pillar](https://en.wikipedia.org/wiki/Light_pillar)? Seems like maybe those only form in cold weather.  
> **username_1**: How cold was the air over Boston when the picture was taken?  
> **username_0**: It was definitely **not** a crepuscular ray, the edges of which could not appear parallel unless observed from an angle near the sun, I think. We were thinking it could be something like a sun pillar--I didn't know that was the term, but the same thing happens on water when there are small ripples.  
> **username_3**: Altohugh I'd given username_1 an up-tick, I think I agree. Crepescular rays are quite common (I saw some brilliant ones a few minutes ago here in TX) and as you say they never appear parallel.  

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