Difference WikiScience

Difference Between Dawn and Twilight

Main Difference

The main difference between Dawn and Twilight is that Dawn is the period when the sun is about to rise, and there is twilight in the sky, whereas Twilight is the time between dawn and morning when the sun is about to rise, and there is semi-darkness in the sky.

Dawn vs. Twilight

Dawn is the period when the sun is about to rise, and there is twilight in the sky, whereas twilight is the period between dawn and morning and dusk and night. Dawn is categorized as astronomical dawn, nautical dawn, and civil dawn; on the other hand, twilight is categorized as civil twilight, nautical twilight, and astronomical twilight.

ADVERTISEMENT

Astronomical dawn is the darkest phase of dawn; on the contrary, nautical twilight and astronomical twilight are darkest phases of twilight. The time period of dawn is before sunrise; on the flip side, time period of twilight is before sunrise and sunset.

As the darkest phases, there are also light phases of dawn and dusk, and civil dawn is the luminous phase of dawn; on the opposing side, civil twilight is the luminous phase of twilight. Dawn can be observed before twilight, whereas twilight can be observed after dawn and dusk. Dawn occurs once in 24 hours; conversely, twilight occurs twice in 24 hours. During astronomical dawn, stars and distant objects are visible to the naked human eye; on the other hand, bright stars and objects are visible during astronomical twilight.

ADVERTISEMENT

Comparison Chart

DawnTwilight
It is the period when the sun is about to rise, and there is twilight in the sky.It is the period between dawn and morning and dusk and night.
Types
Astronomical dawn, nautical dawn, and civil dawn.Its types are civil twilight, astronomical twilight, and nautical twilight.
Dark Phases
Astronomical dawn is the duskiest phase having no visibility.Nautical twilight and astronomical twilight are duskiest phases with very little visibility.
Time Period
Before the sunriseBefore sunrise and sunset
Occurrence
Can be observed before twilightCan be observed after dawn and dusk
Brightest Phase
Civil dawn is the brightest phase of dawn.Civil twilight is the most illuminated phase of twilight.
Duration
It occurs once in 24 diurnal courses.It occurs twice in the diurnal course.
Visibility of Stars
Visible during astronomical dawn.Bright stars are visible during astronomical twilight.
Visibility of Objects
During civil dawn, objects are visible.During civil twilight, objects are apparent.
ADVERTISEMENT

What is Dawn?

The word “Dawn” is originated from old English, meaning “to become day.” It is the time depicting the beginning of the day before sunrise. It is the appearance of low sunlight, which is scattered in the sky.

Dawn is categorized into three types based on the amount of sunlight in the sky. These are astronomical dawn, nautical dawn, and civil dawn. During astronomical dawn, the center of the sun is 18 degrees below the horizon. In nautical dawn, its center is 12 degrees below the horizon, and during civil dawn, its center is 6 degrees below the horizon.

Astronomical dawn starts when the sunlight penetrates the upper atmosphere of the Earth, which scatters it, illuminating the lower atmosphere of Earth. At this time, the light of stars starts to become dim. At the place where there is air pollution, astronomical dawn is indistinguishable from night. Astronomical dawn lasts when nautical dawn starts.

Nautical dawn starts when sun rays touch the Earth’s atmosphere at an angle of 12 degrees. At this event, there is enough light in the sky that land and water can be distinguished. But it is still dark, so outdoor activities cannot be accomplished. Nautical dawn ends at the beginning of civil dawn.

Civil dawn occurs when sun rays touch the horizon at 6 degrees, and the sky is somewhat orange and red in color. In that light, various objects can be distinguished, but the day has not risen yet. Some planets and bright stars are visible at that point. Civil dawn lasts until sunrise.

What is Twilight?

Twilight is the period between dawn and sunrise and sunset and night when there is semi-darkness in the sky. Twilight is due to illumination of the lower atmosphere of Earth when the sun is below the horizon. It is neither completely dark nor light. The intensity of twilight depends upon the distance of sunlight from the horizon. Farther, the sunlight darker is the twilight.

When the sun is 18 degrees below the horizon, the twilight is almost zero. This is when the day starts to arise. Twilight is categorized into three types, civil twilight, nautical twilight, and astronomical twilight. Civil twilight is the brightest, whereas nautical and astronomical twilight is darkest.

Civil twilight surfaces is when the sun is 6 degrees under the sky sill and deters at sunup in the morning and sunset at night. During this time, various objects can easily be distinguished, and distant stars can be seen with the naked eye.

Nautical twilight begins when the center of the sun is at 12 degrees below the skyline and ends when it is at 6 degrees below the horizon. It is proceeded by civil twilight. At this time, land and water cannot be distinguished, and there is darkness. But the human eye can make out the boundaries of different objects.

Astronomical twilight begins when the core of the sun is 18 degrees underneath the sphere of Earth. During this period, there is complete darkness, and the sky is not illuminated by any light at all.

Key Differences

  1. Dawn is the period when the sun is about to rise, and there is twilight in the sky, whereas twilight is the period between dawn and morning and dusk and night.
  2. Dawn is categorized as astronomical dawn, nautical dawn, and civil dawn; on the other hand, twilight is categorized as civil twilight, nautical twilight, and astronomical twilight.
  3. Astronomical dawn is the darkest phase of dawn; on the contrary, nautical twilight and astronomical twilight are darkest phases of twilight.
  4. The period of dawn is before sunrise; on the flip side, the period of twilight is before sunrise and sunset.
  5. Civil dawn is the most brilliant phase of dawn; conversely, civil twilight is the most illuminated phase of twilight.
  6. Dawn can be observed before twilight, whereas twilight can be observed after dawn and dusk.
  7. Dawn occurs once in 24 hours; conversely, twilight occurs twice in 24 hours.
  8. During astronomical dawn, stars are visible to the naked human eye; on the other hand, bright stars are visible during astronomical twilight.
  9. During civil dawn, objects are visible; on the conflicting side, objects that are visible during civil twilight.

Conclusion

So, Dawn is the period before twilight and occurs only once in a day, and Twilight is period before sunset and sunrise, which occurs twice in a day.

Harlon Moss

Harlon currently works as a quality moderator and content writer for Difference Wiki. He graduated from the University of California in 2010 with a degree in Computer Science. Follow him on Twitter @HarlonMoss