The difference between stars and planets in our solar system

15th November 2019

At night time, there are millions of tiny sparkling lights in the sky some are stars and some others are planets. It can be difficult the tell the difference between a star and a planet sometimes, but what is the real difference? By definition, a star is a celestial object that emits its own light due to a chemical reaction at its core. Some stars can appear brighter than others due to their size and their distance from earth, click here to read about the 10 brightest stars in the night sky. A planet is a celestial body that orbits around the star in its solar system and gets its glow from the suns light reflecting from the planets face.

What is the difference between the twinkle of stars and planets?

There are over 10,000 stars visible by the naked eye in the dark sky at night, but have you ever wondered if you’re really looking at a star or the planets in our solar system? One of the easiest ways to tell is the way that the light twinkles. As the stars that we can see with the naked eye are many light years away and emit their own light, when their light eventually enters the different layers of the Earth’s atmosphere, it has bent and been disrupted, causing the star to twinkle. The planets in our solar system are a lot closer to Earth than the stars are, meaning that the light that they give is brighter than stars, although planets do not emit their own light. The sun is a point of light for all of the planets in our solar system, therefore the light that we see from the other planets in our solar system is a reflection of the light from our sun being reflected from that planet.

The difference between the movements of the stars and planets in our solar system

In Ancient Astronomy, in order to distinguish whether or they were looking at a planet or a star, astronomers would study the movement of that specific source of light over the course of a few nights. Planets, like the sun and the full moon, rise and set and follow a celestial path across the night sky. While stars do move, they move in a differently in comparison to the planets in our solar system. Stars move in a circular pattern around the North Star, therefore, if the light that you see appears to move in a straight line over the course of a few nights, it is most likely a planet!

The colour of the planets in our solar system

If you have figured out the difference between the stars and planets in the night sky, how can you tell which planet that you are looking at? One way to tell the difference is by observing the colour of the planet. Not all the planets in our solar system have a specific colour, however the most prominent planets in the night sky can appear to have some sort of colouration. It is recommended to use a telescope on a clear night if you are trying to distinguish the colour difference between the planets in the night sky.

1. Mercury – Gray or Brown

2. Venus – Pale Yellow

3. Mars – Varies between pale pink and bright red. The colour of Mars is affected by its brightness, which varies on a two-year cycle

4. Jupiter – Orange with white bands

6. Saturn – Pale gold

7. Uranus and Neptune – Pale blue, however, they are not visible to the naked eye.

The easiest planets to spot in the night sky are Mercury, Venus and Mars. They can even be seen with the naked eye on a clear night if you know where to look and are visible almost all year, except for short periods of time where they are a little too close to the sun. Keep reading to find out how you can view each of these planets in the night sky!

How to find Mercury in the night sky

Mercury is the smallest of the planets that is visible to the naked eye and shines as an evening star in the western sky, setting around about an hour after the sun sets. In the eastern sky, Mercury can be seen rising about one hour before the sun. If you are looking for Mercury in the night sky, you must have a clear, unobstructed view of the horizon. You may find that Mercury appears as a bright star with a yellowish hue.

How to find Venus in the night sky

Venus, the planet most similar to the size of Earth, can always be seen shining brightly from Earth with a steady light. Venus is seen in the mornings from January to June (where it will be at its brightest) but then disappears until Autumn due to its close proximity to the sun. In Autumn, Venus will return to the night sky in the evenings after dusk from October to December.

How to find Mars in the night sky

The large red planet, Mars, can be seen from Jan to July and then disappears until Autumn, similar to how Venus does. Mars begins shining at a magnitude of +0.5 but will spend the next few months distancing itself away from Earth and gradually diming as it gets closer to the sun.

So, was it a planet or a star that you saw in the dark night sky? Unfortunately, you cannot name planets, as they are already named, but you can buy and name a star with Star-Name-Registry! With a variety of different packages available, there is a name a star gift to suit everyone!