When is Twilight?

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I googled it and it says ‘before sunrise and after sunset’ but I don’t understand how that makes sense because one is AM and the other is PM

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Anonymous 0 Comments

‘Twilight’ means not completely light or dark, so it can occur when the sun is rising and when it is setting. It can also mean the way a mostly dark room with one candle looks, or when you are deep underwater in a cloudy lake on a sunny day. It isn’t usually used as a specific time of day, but you could say, for example ‘deer come out early in the day and go to the waterhole at twilight.’

The phrase ‘the twilight zone’ comes from high altitude pilots at the dawn of the space Age. They noticed that as the atmosphere got thinner the sky got darker. The ‘twilight zone’ was the area where it seemed light and dark at the same time.

Anonymous 0 Comments

Twilight is not “an official time” regarding AM or PM, it’s more of just “an amount of light”.

Specifically it’s when the Sun is longer *directly* line of sight from your eyes to the Sun (meaning it’s just below the horizon) BUT some Sunlight is still hitting the atmosphere and reflecting down to you, meaning the sky still has a glow to it.

So basically, Twilight is that time after the sun has set but the sky still has some brightness or that time as the sky begins to get brighter but the sun hasn’t actually risen yet.

Anonymous 0 Comments

There is twilight both in the morning and at night. In the morning it is between dawn and sunrise and in the evening between sunset and dusk.

It is the period when you receive sunlight that is scattered in the atmosphere but not in direct sunlight because it is below the horizon.

There are three types of twilight: civil, nautical and astronomical.

Civil twilight is when it remains bright enough so you can do daytime activities outside without artificial light like reading a book.

Nautical twilight is when you can still see the horizon, ships will be a silhouette against the brighter sky behind them.

Astronomical twilight is when there is no scattered light that disturbed astronomical observation. This period will be so dark you call it night.

Today Civil Twilight is when the sun is less than 6 degrees below the horizon. Nautical is less than 12 degrees and astronomical is less than 18 degrees. The origin of the definition of what the text above says

Anonymous 0 Comments

Twilight is when the sun is below the horizon but the ground is lit from its light scattered in the the atmosphere. The higher parts of the air can see the sun at that point. In the evening twilight happens after sunset, and in the morning before, although I rarely hear this word used in the latter case. Twilight is longer near the Earth’s poles than around the equator because the planet’s rotation makes the sun appear to descend at a more level path.

Anonymous 0 Comments

30 minutes before sunrise, and the 30 minutes after sunset.

There are actual legal definitions in different places, for example in the U.K. car headlights have to be used during night, and twilight is defined as 20 minutes before and after sunrise and sunset respectively.

Anonymous 0 Comments

In the morning, twilight is when the sun hasn’t yet risen but the sky is already illuminated by the sun from below the horizon. In the evening, the same thing happens after the sun has dipped below the horizon, but sunlight is still making its way over the horizon to illuminate the sky. The atmosphere scatters the sunlight so some of it gets reflected back down to the ground, illuminating the surroundings and brightening the sky.

The lower the sun dips, the less of its light makes it over the horizon. When it reaches 18° below the horizon, the brightness becomes nearly 0 and that’s when true night begins (or ends). The period after sunset but before this point is called “dusk”, and the period after the sun comes back above -18° but before sunrise is called “dawn”.

Twilight can be subdivided into three phases: civil, nautical and astronomical twilight, and they end at -6°, -12° and -18°, respectively. Civil twilight is called this way because it roughly corresponds to the period that you don’t need artificial light in towns and cities – it’s still bright enough to walk around without bumping into things. Nautical twilight gets its name from the fact that it is still bright enough for sailors to see the horizon and navigate by it. Astronomical twilight is when (though it’s not quite night yet/anymore) you can make astronomical observations of things like (reasonably bright) stars (but not fainter objects like galaxies or nebulae). Of course, these definitions are a bit overly neat (it would be a great coincidence if these experiences coincided exactly with 6-degree changes in the elevation of the sun).

How long twilight lasts depends on the season and your latitude. In some places at higher latitudes, the sun never dips below 18° at night in (mid) summer. So even though the sun does set, it never gets darker than twilight, meaning twilight (technically) lasts the whole period between sunset and sunrise. E.g. England, the Netherlands, Belgium, Poland and most of Germany never get darker than astronomical twilight in mid summer. In Scotland, Denmark and southern Sweden, it gets no darker than nautical twilight, and in Finland and Iceland it gets no darker than civil twilight. Within the polar circle, the sun doesn’t set at all in mid summer. At these higher latitudes, each phase of twilight also lasts longer.

Anonymous 0 Comments

The Twilight criterium usually occurs on the last weekend of April in Athens Georgia USA.

Yes, I’m aware that this is probably not what you were referring to. But the event is indeed called “Twilight”.

Anonymous 0 Comments

Twilight is the time of day when the sun has begun lighting up the sky, but the sun itself is still below the horizon and not visible yet.

It usually happens just after sunset and just before sunrise, for obvious reasons.

Think of a time when the sky has seemed “lit up” but the ground has still been in darkness.

Anonymous 0 Comments

Twilight is the time between sunset and full dark, or the time between full dark and sunrise. There is a window of time between these where it’s not dark, nor is it really light out. This time is called twilight.