For the next two weeks keen skywatchers in the Northern Hemisphere can hunt down one of the most elusive astronomical phenomena visible in the sky – the Zodiacal Light. This pyramid-shaped beam of light is easily mistaken for lights of a far-off city just over the dark horizon in the countryside and has also been called the ‘false dawn’. But this light is more ethereal; it is caused by sunlight reflecting off cosmic dust between the planets.
The next two weeks in September will be the best time to track down this ghostly light in the eastern sky before morning twilight. But you will have to head out of the city into a dark location to spot it because it can be easily lost in light pollution. Look towards the eastern horizon, where the sun rises, about an hour before it comes up.
Ancient Romans thought this ghostly glow was due to far-off camp fires below the horizon, while the ancient Greeks speculated that it must be caused by distant volcanic explosions. Centuries later, by the mid sixteenth-century people thought that the Zodiacal Light was the outstretched atmosphere of our Sun.
Zodiacal Light results from sunlight reflecting off a vast field of meteoric dust that lies in the plane of the solar system and stretches out far beyond Earth. It actually formed when the solar system was first evovling . Billions of dust-sized particles that were left behind, after the planets formed about 5 billion years ago. It’s amazing to think that about 40% of the overall light in the night sky can be attributed to this Zodiacal dust cloud.
Tags: False Dawn, Zodiacal Lights
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