What Causes This Phenomenon? On a recent flight from Minneapolis to Denver I observed this phenomenon looking out the right side of the plane. We were at 35,000 feet. The sun was...

jmdenver Loc: Colorado

On a recent flight from Minneapolis to Denver I observed this phenomenon looking out the right side of the plane. We were at 35,000 feet. The sun was behind and slightly to the left of the plane. The cloud cover was extensive, lasting for several hundred miles and the "rainbow" persisted for about 1 1/2 hours of the flight. Is this a sundog or something else?

EstherP

I've seen the phenomenon right from the earth's surface, my backyard. Here a couple of websites explaining it much better than I can, found by Googling "Rainbow around the sun"

http://www.abcactionnews.com/dpp/news/science_tech/whats-that-rainbow-ring-around-the-sun-its-a-22-degree-halo-formed-by-ice-crystals

http://www.komonews.com/weather/faq/4308372.html

http://www.carolinalive.com/news/blog_post.aspx?id=605872

EstherP

jmdenver Loc: Colorado

Thanks EstherP. I too have seen this from the ground, but that occurs when one is looking back at the sun. That is not the case in this situation. Possibly, it is just the result of the sunlight reflecting off the clouds. I was also surprised by the longevity of the event.

Botann Loc: SE of Seattle

It's called a 'Glory'.
It can be seen directly opposite the sun.
Here's an example of one opposite from the sun from earth on Astronomy picture of the day for Dec 2, 2012.

http://apod.nasa.gov/apod/astropix.html

Mike

Bunko.T Loc: Western Australia.

jmdenver wrote:

On a recent flight from Minneapolis to Denver I observed this phenomenon looking out the right side of the plane. We were at 35,000 feet. The sun was behind and slightly to the left of the plane. The cloud cover was extensive, lasting for several hundred miles and the "rainbow" persisted for about 1 1/2 hours of the flight. Is this a sundog or something else?

I've seen it numerous times. The first in a small plane, Cessna 182, flying close to clouds. The pilot purposely manuevered the plane to cast its shadow on the clouds & it had this vivid rainbow halo around it. It's caused by the same phenomenon as that which produces rainbows. A pressure differential by the plane & with moisture in the air & light shining through. Scientists would describe it better no doubt. I've also seen it on long flights to s/e asia where there's clouds nearby.

krispix Loc: London - UK

It's a rainbow. This happens when the sun is directly behind the viewer and is most prominent against a cloud. If you were standing on the ground you would only see half of it, hence it appears as a semi-circular 'bow'

andypilot Loc: Dubai UAE

This is called a corona rainbow and it is slightly different spectrum to a normal rainbow.

They are round as there is no horizon in the way to stop you seeing the full reflection.

Hope that helps

Andy

jmdenver Loc: Colorado

Botann wrote:

It's called a 'Glory'.
It can be seen directly opposite the sun.
Here's an example of one opposite from the sun from earth on Astronomy picture of the day for Dec 2, 2012.

http://apod.nasa.gov/apod/astropix.html

Mike

Bingo! I appreciate your help. Calling it a "Glory" enabled me to do a bit more research. Many Thanks.

jmdenver Loc: Colorado

Bunko T,

Thanks for the info. I appreciate it.

jmdenver Loc: Colorado

andypilot wrote:

This is called a corona rainbow and it is slightly different spectrum to a normal rainbow.

They are round as there is no horizon in the way to stop you seeing the full reflection.

Hope that helps

Andy

Thank you, Andy. This is most helpful.

jmdenver Loc: Colorado

krispix wrote:

It's a rainbow. This happens when the sun is directly behind the viewer and is most prominent against a cloud. If you were standing on the ground you would only see half of it, hence it appears as a semi-circular 'bow'

Thank you, krispix. I appreciate the information.

CaptainC Loc: Colorado, south of Denver

I always called it the "pilot's halo." :-)

Daryl New Loc: Wellington,New Zealand

Interesting,have never seen this,thanks for post.

Mudshark Loc: Illinois

LSD will fully expose this...

mikeyatc Loc: Reno,NV/Folsom,CA

refraction of light