There are things that happen around us that we do not question, because we see them as normal. Like the fact that we live on a ball-shaped planet located in a universe that has a burning star called the Sun at its centre. And no one questions this or finds it weird.
We get up when it’s daytime and we go to sleep when it’s night time; night and day seems so normal to us like breathing. But how do these two things happen?
Day vs Night
According to Education Victoria the Earth is one of several planets that orbit the sun, while the moon orbits the Earth. The Earth is a sphere, while the sun is a nearby star full of gas that radiates light and heat as products of nuclear reactions.
Twinkl states that daytime is the time of day when you can see the sun in the sky, while night time is when the sun is down and it’s dark with the moon visible. We get day and night because the Earth rotates on an imaginary line called an axis. During daytime Earth is facing the sun and when Earth rotates it moves away from the light into the darker side. 24 hours equals one day and we experience daytime and night time within those hours.
According Ask Difference, the day is a unit of time. It’s the period of time when Earth completes one rotation, that means that a single spin around the whole planet takes 24 hours to finish, which is why our planet is always moving. Encyclopaedia Britannica highlights that a day begins at midnight and runs through 24 hours, until the next midnight.
A day is separated into two sets of 12 hours for ordinary timekeeping purposes; hours from midnight to noon are AM (ante meridiem) and those from noon to midnight are PM (post meridiem, “after noon”). Britannica says that the word ‘day’ means the 24 hours between midnight and midnight, instead of daylight hours between sunrise and sunset. So, it’s not just about when its starts to get light but it’s about the time as well.
According to the dictionary night is the period of darkness between sunset and sunrise. People use night as the time that they are going to sleep, using the infamous phrase, “good night” as a form of saying they are going to sleep. The night is technically the time from sunset to sunrise when it is still dark out.
The Earth orbits and rotates and you may think these things are the same but they aren’t. The sun is the centre of the universe and all the planets are circling it, which is what we call orbiting. Earth is also always rotating as its circling the sun. Rotating means spinning, like how a ball spins – Earth is exactly the same but slower and bigger. According to Generation Genius the Earth makes one complete rotation on its axis. What is the axis? Well, it is the imaginary line through the earth that extends from the North Pole to the South Pole.
One rotation is 24 hours. Generation Genius claims that if the sun is visible in the morning starting around 6am, the Earth will spin completely around by the next morning at 6am and you will see the sun in about the same place. Now what does this have to do with seasons? A lot.
Twinkl states that the Earth is divided horizontally by an imaginary line called the equator. The half of the Earth above the equator, which includes countries such as the UK, USA and China, is called the Northern Hemisphere. The half below the equator, which includes countries such as Argentina, Australia, Brazil and South Africa, is called the Southern Hemisphere.
Even divided equally by two imaginary lines, Earth does not sit straight. Our planet orbits the sun on a tilt of 23.5° and because of that we have seasons. According to Twinkl the Northern Hemisphere is tilted towards the sun during the summer months, meaning longer days and hotter weather. During the winter the Northern Hemisphere is tilted away from the sun, meaning shorter days and colder temperatures.
Here are some fun facts about the day and night:
• At any minute, half of the world is in the light of daytime and half is in the darkness of night-time.
• The shortest day of the year is called the winter solstice and the longest day of the year is called the summer solstice.
• In London, the longest day is about 16 hours and 39 minutes and the shortest day is around 7 hours and 45 minutes.
• Day has different stages: midnight (exactly 12:00 am), morning (from 12:01 am to 11:59 am), noon (exactly 12:00 pm), afternoon (from 12:01 pm to 6:00 pm), evening (from 6:00 pm to 11:59 pm).
• Night is considered a part of the day when it’s dark and people are asleep.
There are things about our beautiful world that will never stop being mesmerising, like sunrise, before the rush of reality starts in the morning. Or like stars decorating the night sky, or the moon that humans are still obsessed with to this day. There are things that we will truly never fully understand, but we can still appreciate their beauty.
Want to know why the sky is blue? Read more here.
Tell us: What have you learned about day and night?