Vor einiger Zeit bemerkte ich, dass die Kontrails von Raketen, die in hohen Höhen in der Dunkelheit abheben, viel heller aussehen als auf der Erdoberfläche. In letzter Zeit wurden zahlreiche Fotos von ballistischen Raketen vom Iran gestartet, auf denen dieses Muster deutlich sichtbar ist. Zunächst sind die Kontrails schwach und rötlich, aber wenn sie eine bestimmte Höhe erreichen, beginnen sie hell in weißem Licht zu leuchten. Dies deutet darauf hin, dass der Beleuchtungsgrad in der Höhe viel höher ist als an der Erdoberfläche. Es kann nicht das Licht der untergehenden Sonne sein, weil sein Licht rot und nicht weiß ist. Was ist der Grund dafür?
https://www.reddit.com/gallery/1lhm1j3
9 Kommentare
You are exactly correct. The condensation trail is being lit up by the sun. That’s why the bottom of it is shades of red and yellow because from the perspective of the condensation, the sun is setting and producing lots of red and yellow light, but as the rocket goes higher, the sun is also higher relative to the location of the contrails meaning the light is whiter like during a regular day.
Probably because there’s more light in the upper atmosphere. I don’t know the timing of these pictures, but my best guess is that it’s similar to the “jellyfish” you can see sometimes on falcon 9 launches.
The contrail is high enough that the sun is back above the horizon. The reddish part is where the sunlight is still filtered by atmosphere, the brightly lit part is where there is a direct line of sight between sun and trail without atmosphere?
Or did I misunderstand the question?
If it’s near dawn or dusk, yes it is the sun, the rocket has launched out of Earth’s shadow and is being lit up by the sun. The red light would be the same reason the sky looks red at sunrise and sunset, the light on the plume is literally light that has gone through a sunset.
If it’s in the middle of the night, then I’m not sure because this really looks like the sun, but my best guess is that it’s it’s probably because rocket plumes are genuinely bright. Solid rocket motors, the type typically used in missiles because they’re simpler and faster to launch, leave effectively dust glowing really bright because it’s really hot. The particles then cool down, and as they do that they cool from blueish light to white to red as hot things do. [Here is a video ](https://www.youtube.com/watch?v=BD1W8Sgp9Z8)of a nightime shuttle launch, you can see that the plume is bright when it leaves the exhaust and cools and dims as it leaves.
Again though, I’m really not certain about that second one, this really looks like the sun. Night launches don’t typically glow. The 2nd one is just the least implausible explanation I could think of
Great question! There’s more air at lower altitudes so the light is much dimmer since the light has to travel through so much air. As you head higher in altitude the air gets thinner so the light becomes more intense. It’s the same reason you can look directly at the sun during a sunset and not hurt your eyes.
I remember an interview with Gene Cernan of Gemini 10, Apollo 10, and Apollo 17 fame where he said that in space you can barely get your eyes to look in the direction of the sun, much less look directly at it without some sort of eye/face shielding. It’s that intensely bright. On Earth you can maybe look at it for half a second before you have to look away.
>>it cannot be the light of the setting sun, because its light is red
Dude… when the sun is setting in one point it is high in the sky elsewhere! The red tint is due to Raleigh scattering through the atmosphere, not a change in hue of the sun itself.
When the trail is high enough, it sees the sun unobstructed by the atmosphere and is shining white.
It isn’t lightning and it’s poorly worded question.
Light diffraction. More dense atmosphere means that there is more diffraction. More diffraction means different colors.
As you get higher and the atmosphere gets thinner, the rocket exhaust spreads out into a wider cone as it exits the nozzle. It’s due to the exit pressure being higher than the ambient pressure. The trail of exhaust can get lit up by the sun and it’s more intense with less atmosphere blocking it.