Full rainbow over town

starfinder · Post by **starfinder** » Thu Feb 09, 2006 7:41 pm

There was a full rainbow right over town today, from about 6.45pm to 7.00pm. A real sight to behold!

Here is a stitched panorama photo of it, from two shots at 18mm in a DSLR.

The rainbow appeared to have stretched from around Raffles Place (Chartered Bank building) to Scotts Road (near the junction with Stevens Road).

Using Google Earth to measure, that's a straight line distance of 3.3km. Taking that as the diameter, the circumference of the circle was Pi x d = 10.37km. Therefore, the length of the rainbow was 5.2km, i.e. a half circle.

Now, I still don't understand how rainbows are formed. I know about the refraction of white light into its constituent colours, but why are they circular in shape? Why not triangular, in straight lines, etc. And why not upside down, or sideways? Or dozens of small circles in the sky? Why usually just one large rainbow? Why does it start where it does, and end where it does?

Anyone knows?

Post by **weixing** » Thu Feb 09, 2006 7:50 pm

Hi,
See below:
http://www.weather-photography.com/tech ... rainbowfaq

Have a nice day.

jermng · Post by **jermng** » Thu Feb 09, 2006 7:56 pm

It might be longer than you think ... I saw it all the way home from town to Bt Panjang .... here's a pic of it taken with my phone ... all the way in Bt Panjang ...

So I guess good things can come from cloudy days ..

Bergkamp_ · Post by **Bergkamp_** » Thu Feb 09, 2006 8:07 pm

a rainbow is shape of circle.. i dun know y.. but if u look from plane.. u will see the rainbow that is round.. saw that is some documantary..

neoterryjoe · Post by **neoterryjoe** » Thu Feb 09, 2006 10:18 pm

yes, saw them in nus.. the inner and the outer one... v nice..think was the first time i saw one stretching from the horizon and back..

Traveler · Post by **Traveler** » Thu Feb 09, 2006 10:52 pm

Yeah saw it on my way from CCK to buona vista. A really bright and intense one and long lasting. Many passer-bys stopped to admire it. Wonder how many of them noticed the fainter one...

qu1xs1lv3r · Post by **qu1xs1lv3r** » Thu Feb 09, 2006 11:25 pm

haha i saw it too!! took a pic on my phone but too lazy to upload!!

Post by **Airconvent** » Thu Feb 09, 2006 11:31 pm

on the way back from KL some months back...I saw 2 complete rainbows!
it was the first time I ever saw 2 complete semi-circle ones together! what a sight....but too bad it was drizzling and I had locked the camera away in the boot...

starfinder · Post by **starfinder** » Fri Feb 10, 2006 8:17 am

Thanks for the link.

Hmmmm.... the full rainbow really looked as if it ended at Raffles Place. A friend of mine at the East Coast Park said he saw a rainbow. Maybe the one at Bt. Panjang was a different one.

Yes, there was an outer rainbow, but it was very short, faint and lasted only a while. When that one faded, the inner rainbow blossomed into a full semi-circle, as in the photo above.

Here is a photo of segments of the inner and outer rainbows.

BTW, the most number of rainbows I've ever seen was in Hawaii in December 2001. I went to 3 islands (Oahu, the Big Island of Hawaii, and Kau'ui) and saw lots of rainbows nearly everyday. I must have seen dozens in the 10 days I was there. Quite amazing. There was once I saw 3 rainbows at once in 3 different areas of the sky. Here in S'pore, I see them only about 2-3 times in a year. I wonder why such a difference.

sTiCkY · Post by **sTiCkY** » Fri Feb 10, 2006 8:34 am

i saw it too!! from my home in jurong. why are there like 2 rainbows??

SingAstro

Full rainbow over town

Full rainbow over town

Rainbow