... or would it need air (instead of being in a vacuum)?
2007-12-29 07:19:51 · 7 answers · asked by Kelly 7 in Science & Mathematics ➔ Astronomy & Space
A rainbow requires spherical drops of water, which aren't present in the tail of a comet. On Earth, you can also get various forms of colored light effects from ice crystals in the atmosphere, but that probably won't happen in the tail of the comet either, for two reasons. The first is that the ice crystals that cause sundogs and other such phenomena are formed by atmospheric processes that aren't present in a comet. The second is that these uniform crystals must all align the right way to cause colored reflections. On Earth, this is caused by the combined effects of gravity and atmosphere as the ice crystals fall through the atmosphere. Even if suitable ice crystals could form in the comet's tail, I don't think there is anything there that could cause a similar alignment.
2007-12-29 08:55:01 · answer #1 · answered by injanier 7 · 0⤊ 0⤋
This site should award extra bonus points for such excellent questions!
I don't know, but I suspect that it may be possible to see a small part of the arc of a rainbow depending on the geometry of the observation and the nature of the ice vapour.
A rainbow is seen when light reflects from water droplets. The light is reflected and spread out into colours within each droplet. A similar effect might happen if the vater vapour in the comet tail condensed into particles with suitable shapes, sizes, internal properties or surface features.
A halo is probably more likely. A bright star seen through a tail might just produce one.
2007-12-29 13:10:19 · answer #2 · answered by Quadrillian 7 · 0⤊ 0⤋
No. Rainbows result from a double reflection of light waves inside a drop of liquid water.
Ice has a different index of refraction and does not contribute to rainbows. One phenomenon you might have seen that is caused by ice crystals is a halo around the sun or moon -- this is called the 22-degree halo.
http://www.lumis.com/tag/halo/page1/
2007-12-29 07:36:58 · answer #3 · answered by MVB 6 · 0⤊ 0⤋
No. For a rainbow you need light passing through spherical droplets of water. Ice crystals are not spherical.
2007-12-29 07:29:15 · answer #4 · answered by Charlie149 6 · 0⤊ 0⤋
You can see it so it must reflect light.
The fact that you can see it means that it restricts light passing through it so it would cast a shadow.
The darkness of the shadow would depend on it's density,there would have to be an object behind it to cast the shadow on.
2007-12-29 07:27:32 · answer #5 · answered by Billy Butthead 7 · 0⤊ 0⤋
Yes, if the light passes through the tiny micro drops acting like microprisms.
2007-12-29 13:32:59 · answer #6 · answered by Asker 6 · 0⤊ 1⤋
no
2007-12-29 08:19:27 · answer #7 · answered by pawan1 2 · 0⤊ 0⤋