Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: paul.fr on 18/05/2007 19:53:08

Title: viewing rainbows from above.
Post by: paul.fr on 18/05/2007 19:53:08
Do rainbows appear circular when seen from an aeroplane flying above them?
Title: viewing rainbows from above.
Post by: daveshorts on 19/05/2007 22:51:05
A rainbow allways forms in a circle about 21° around the point directly opposite the sun, normally at least half of this circle should be below you and there is little rain below ground so you don't see it. It also means that a rainbow could only be directly below you if the sun was directly above you, as clouds are normally required to be above rain this is quite unlikely even if you were at the equator.

However in a plane if you are high enough up that there is enough rain 21° below the horizontal to produce a good rainbow you will see a circular rainbow although it won't be below you.
Title: viewing rainbows from above.
Post by: kdlynn on 20/05/2007 03:35:12
i didn't see any rainbows!
Title: viewing rainbows from above.
Post by: daveshorts on 20/05/2007 10:39:28
Rainbows in planes are going to be at least as rare as on the ground, you need to be in a position where there is strong sunlight on one side of the plane and rain on the other. You will also have to be looking out of the window at the right time.
Title: viewing rainbows from above.
Post by: lyner on 21/05/2007 16:08:21
Quote
you will see a circular rainbow although it won't be below you.

Why not?  A rainbow is visible when your back is to the Sun. At mid day, with rain below you, you could easily see  part of a rainbow down there.   All that is necessary if for sunlight to be falling directly on some raindrops.
I'm sure that I've seen the 'inverted' bit of a rainbow whilst walking in mountains, even.
Title: viewing rainbows from above.
Post by: daveshorts on 23/05/2007 09:04:15
However for the rainbow to be directly below you, you would need rain below you without clouds above you, which is probably quite unlikely...
Title: viewing rainbows from above.
Post by: skysky3003 on 16/09/2007 19:13:43
Please help me
I need to know why and how rainbows move when you chase them???
I need an awser as soon as possible