Dawn Vs Twilight [What Is The Difference Between These?]

Astronomy Scope is reader-supported. Just so you know, I may collect a share of sales or other compensation from the links on this page - at no additional cost to you. This includes Amazon.

Dawn and twilight are terms used to describe particular times of day, but what are they and how are they different? I spent some researching to find out. Here is what you want to know.

So, what is the difference between dawn vs twilight? Dawn and twilight are two different periods. Dawn occurs in the morning, it is the first appearance of light before sunrise. Twilight, is the period between dawn and sunrise, or sunset, and dusk when light is still visible from the Sun. Dawn only happens in the morning. Twilight happens during both sunrise and sunset.

x
Astronomy Scope

Quite the tricky one to get your head around.

Nevertheless, both are related to the movement and positioning of the sun in relation to earth.

Let us now take a closer look at dawn and twilight in further detail to better understand the differences involved.

What Is Dawn?

Dawn is the term given to the first appearance of light in the sky before sunrise.

Dawn is technically the beginning of twilight, and occurs before the sun rises.

At this stage, the sun is still below the horizon, and as such, sunlight is relatively weak.

To help differentiate further, dawn has been broken down into three distinct phases:

  • Astronomical dawn the period when the Sun is 18 degrees below the horizon. During this time, the sky will not be entirely dark.
  • Nautical dawn the period where the Sun is 12 degrees below the horizon. With more light, it is possible to start to observe objects and items.
  • Civil dawn is the period where the Sun is 6 degrees below the horizon. This is when you can begin to do things without supplemental street lighting.

Dawn only occurs in the morning.

What Is Twilight?

Twilight is the term given to the period between dawn and sunrise, or between sunset and dusk.

During this time there will be a soft glowing light from the sky. While the sun is below the horizon, the light is caused by a reflection of the suns rays from the atmosphere.

In other words, twilight is simply the time between daylight and darkness.

We experience twilight because Earth has an atmosphere, that light small amounts of light can pass through. This results in light in the sky even before the sun has risen or set.

Again, there are three types of distinct phases:

  • Astronomical twilight the period when the Sun is 18 degrees below the horizon.
  • Nautical twilight the period where the Sun is 12 degrees below the horizon.
  • Civil twilight is the period where the Sun is 6 degrees below the horizon.

Twilight can occur both during the morning and the evening.

Difference Between Dawn And Twilight

The main difference between dawn and twilight is the time that they each occur. Dawn will only take place in the morning, whereas twilight can take place during the morning and the evening.

Secondly, dawn and twilight are considered as two separate and distinct phases.

Consider it this way:

  • Dawn is the beginning of twilight.
  • Dawn is the beginning of twilight, before sunrise.
  • Twilight occurs between dawn and sunrise, and between sunset and dusk.
  • Dawn is the beginning of twilight.
  • Twilight starts with the dawn.

Is Twilight Before Dawn?

Twilight does not come before dawn, it is in fact the opposite way around. Dawn is the time that marks the beginning of twilight before sunrise.

Finally

Dawn and twilight – it can be confusing for sure.

But put simply.

Dawn is the time before the sunrise, twilight is the period of light that transpires from the incoming or departing Sun.

And while there is a small distinction here. Its important.

Especially to astronomers who are awaiting for true darkness to fall.

From there, they can begin their observations.