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  1. Standard member sonhouse
    Fast and Curious
    08 Aug '10 04:03
    here is an APOD of a double rainbow, I was looking at this image wondering if there could be a triple. Any thoughts?

    http://antwrp.gsfc.nasa.gov/apod/ap100807.html
  2. 09 Aug '10 09:48
    Originally posted by sonhouse
    here is an APOD of a double rainbow, I was looking at this image wondering if there could be a triple. Any thoughts?

    http://antwrp.gsfc.nasa.gov/apod/ap100807.html
    Yes, I am sure I have seen them. You need a particularly clear and bright view with lots of contrast between the rainbow's and the clouds behind. I can't remember if I have seen them with a secondary inside and another outside or if all the secondarys were outside the primary. I think they were all outside.

    --- Penguin.
  3. Standard member PBE6
    Bananarama
    09 Aug '10 19:20
    Whoa...double rainbow...all --- the --- waaayyyyy!!!!! So intense!!!!!!!!
  4. Standard member sonhouse
    Fast and Curious
    10 Aug '10 00:08 / 2 edits
    Originally posted by PBE6
    Whoa...double rainbow...all --- the --- waaayyyyy!!!!! So intense!!!!!!!!
    I've seen a few doubles. I also saw an almost complete circle rainbow, standing on a high cliff. THAT was amazing.

    I wonder if someone in a balloon could see a 360 degree rainbow if they were high enough in the air?

    Can you figure out how high you would have to be to be able to see a 360 rainbow?
  5. Subscriber coquette
    Already mated
    10 Aug '10 03:37
    Originally posted by sonhouse
    I've seen a few doubles. I also saw an almost complete circle rainbow, standing on a high cliff. THAT was amazing.

    I wonder if someone in a balloon could see a 360 degree rainbow if they were high enough in the air?

    Can you figure out how high you would have to be to be able to see a 360 rainbow?
    yes, a lot more are theoretically possible
  6. 10 Aug '10 11:17 / 1 edit
    Originally posted by sonhouse
    I've seen a few doubles. I also saw an almost complete circle rainbow, standing on a high cliff. THAT was amazing.

    I wonder if someone in a balloon could see a 360 degree rainbow if they were high enough in the air?

    Can you figure out how high you would have to be to be able to see a 360 rainbow?
    Yes, someone in a balloon or airplane would see a circle.

    I think the required height would depend on the distance to the rainbow. The angle from sun to raindrops to observer is always at a fixed angle so how far below the observer it goes should be 'easy' to work out using Pythagoras.

    Wikipedia gives the angle at between 40 and 42 degrees from the observers shadow. It also depends on the height of the sun.

    Do a Google image search for "Circular Rainbow"

    --- Penguin.
  7. Standard member PBE6
    Bananarama
    10 Aug '10 13:42 / 1 edit
    Originally posted by sonhouse
    I've seen a few doubles. I also saw an almost complete circle rainbow, standing on a high cliff. THAT was amazing.
    Was this you then?

    www.youtube.com/watch?v=OQSNhk5ICTI

    They wrote a song about it!

    www.youtube.com/watch?v=MX0D4oZwCsA
  8. Standard member sonhouse
    Fast and Curious
    10 Aug '10 14:51
    Originally posted by PBE6
    Was this you then?

    [b]www.youtube.com/watch?v=OQSNhk5ICTI


    They wrote a song about it!

    www.youtube.com/watch?v=MX0D4oZwCsA[/b]
    Yeah, saw that a few weeks ago, I thought he was tripping on acid or something. He claims not however.
  9. Standard member sonhouse
    Fast and Curious
    10 Aug '10 14:53
    Originally posted by coquette
    yes, a lot more are theoretically possible
    I imagine if more are possible they are there staring you in the face when looking at a single rainbow even but too faint or the sky too polluted to pick them up. Wonder if special light filters could suss them out digitally or something?
  10. 11 Aug '10 11:21
    Originally posted by Penguin
    I think the required height would depend on the distance to the rainbow. The angle from sun to raindrops to observer is always at a fixed angle so how far below the observer it goes should be 'easy' to work out using Pythagoras.
    Yes, the distance to the rainbow is the deciding factor.
    I have seen full circles when standing on the ground. It should be relatively easy to replicate using a garden sprinkler with a good spray and a fairly low sun.

    One of the best places to see rainbows is the Victoria falls (I used to live 10km away).
    If the sun is shining you are practically guaranteed a full circle rainbow and double rainbows. I don't think I have seen a triple though.
    I am also told that a moon bow (a rainbow from moonlight) is quite amazing, though I have never seen one.
  11. Standard member avalanchethecat
    Not actually a cat
    11 Aug '10 12:30
    Originally posted by twhitehead
    Yes, the distance to the rainbow is the deciding factor.
    I have seen full circles when standing on the ground. It should be relatively easy to replicate using a garden sprinkler with a good spray and a fairly low sun.

    One of the best places to see rainbows is the Victoria falls (I used to live 10km away).
    If the sun is shining you are practically gua ...[text shortened]... told that a moon bow (a rainbow from moonlight) is quite amazing, though I have never seen one.
    I've seen a moonbow - took me a few moments of confusion to work out that it was the moon that was doing it.
  12. Standard member sonhouse
    Fast and Curious
    11 Aug '10 13:17
    Originally posted by twhitehead
    Yes, the distance to the rainbow is the deciding factor.
    I have seen full circles when standing on the ground. It should be relatively easy to replicate using a garden sprinkler with a good spray and a fairly low sun.

    One of the best places to see rainbows is the Victoria falls (I used to live 10km away).
    If the sun is shining you are practically gua ...[text shortened]... told that a moon bow (a rainbow from moonlight) is quite amazing, though I have never seen one.
    So you think a dude in a hot air balloon could get high enough in the air to see a full circle rainbow from his wicker basket?
  13. 11 Aug '10 15:27
    Originally posted by sonhouse
    So you think a dude in a hot air balloon could get high enough in the air to see a full circle rainbow from his wicker basket?
    As I said, you can see a full circle while standing on the ground. All you need is the water droplets to be close enough. The dude in his wicker basket may or may not be able to get high enough depending on the distance to the water droplets and the angle of the sun.
    If a line 42 degrees below the shadow of the dudes head strikes the rain before it strikes the ground then he will see the full circle (assuming he can see the top and sides too.)
  14. Standard member sonhouse
    Fast and Curious
    11 Aug '10 18:23
    Originally posted by twhitehead
    As I said, you can see a full circle while standing on the ground. All you need is the water droplets to be close enough. The dude in his wicker basket may or may not be able to get high enough depending on the distance to the water droplets and the angle of the sun.
    If a line 42 degrees below the shadow of the dudes head strikes the rain before it strikes the ground then he will see the full circle (assuming he can see the top and sides too.)
    I assume the droplets have to be a certain sized, small window of opportunity, for a rainbow to be visible, so you wouldn't just be near a normal cloud with your hot air balloon. You would have to find the right conditions first. Maybe seeing a rainbow, then launching? Anyone have info on how long a rainbow remains visible from a single spot?
  15. 11 Aug '10 19:30
    Originally posted by sonhouse
    here is an APOD of a double rainbow, I was looking at this image wondering if there could be a triple. Any thoughts?

    http://antwrp.gsfc.nasa.gov/apod/ap100807.html
    Try wearing polarized lenses.