{"id":505023,"date":"2025-06-30T21:29:39","date_gmt":"2025-06-30T19:29:39","guid":{"rendered":"https:\/\/osr.org\/?p=505023"},"modified":"2025-07-01T03:48:27","modified_gmt":"2025-07-01T01:48:27","slug":"stars-vs-planets-how-to-tell-them-apart-in-the-night-sky","status":"publish","type":"post","link":"https:\/\/osr.org\/en-uk\/blog\/astronomy-uk\/stars-vs-planets-how-to-tell-them-apart-in-the-night-sky\/","title":{"rendered":"Stars vs Planets: How to Tell Them Apart in the Night Sky"},"content":{"rendered":"

We\u2019ve all looked up at the night sky and marvelled at the sparkling points of light scattered above us, but it can be easy to forget that not all of them are stars! In fact, some of the very brightest \u201cstars\u201d you can see might actually be planets, right here in our Solar System<\/a>. Spotting planets with the naked eye is easier than you might think – if you know what to look for! In this article, we\u2019ll pit stars vs planets and break down all the key differences, examining why they behave differently in the sky and how you can identify them during your next stargazing session!<\/span><\/p>\n

What Are Stars?<\/span><\/h2>\n

\"A<\/p>\n

Stars<\/a> are massive, luminous spheres of hot plasma held together by gravity. Our Sun is the closest star to Earth and gives us a clue about what stars truly are – gigantic nuclear furnaces burning hydrogen into helium. The stars you see in the night sky are located light-years away from Earth and come in a huge variety of sizes, temperatures, and colours<\/a>.<\/span><\/p>\n

They produce their own light through nuclear fusion, which means the light they emit has travelled an enormous distance before reaching your eyes. Because of this, many stars appear to twinkle due to interference from Earth\u2019s atmosphere affecting the faint starlight.<\/span><\/p>\n

What Are Planets?<\/span><\/h2>\n

\"Jupiter<\/p>\n

Planets, by contrast, are celestial bodies that orbit stars. In our case, that\u2019s the Sun. Unlike stars, planets don\u2019t produce their own light – instead, they reflect sunlight. This is one of the key reasons they look different in the night sky.<\/span><\/p>\n

Five planets are most commonly visible to the naked eye from Earth: Mercury, Venus<\/a>, Mars, Jupiter<\/a>, and Saturn<\/a>. Quite often, you can easily post most of these objects, just so long as you know when and where to look. Because they\u2019re much closer to us than the stars, they shine more steadily and can appear quite bright from here on Earth.<\/span><\/p>\n

Stars vs Planets: Key Differences<\/span><\/h2>\n

\"stars<\/p>\n

Both stars and planets appear as points of light in the sky, so how can you tell the difference? Fortunately, when you’re comparing stars vs planets, there are several easy ways to tell them apart:<\/span><\/p>\n

Twinkling vs Steady Light<\/span><\/h3>\n

One of the most reliable ways to differentiate between stars and planets is how their light behaves. Stars appear to twinkle<\/a>, especially when they\u2019re close to the horizon. This twinkling, or \u201cscintillation\u201d, is caused by Earth’s turbulent atmosphere bending the star’s light in various directions.<\/span><\/p>\n

Planets, on the other hand, shine with a steadier, more consistent light. Because they\u2019re so much closer to Earth and present a larger disc in the sky (even if we can\u2019t resolve it with the naked eye), the light from planets is far less affected by atmospheric distortion.<\/span><\/p>\n

Brightness and Colour<\/span><\/h3>\n

Planets are often among the brightest objects in the night sky, sometimes even outshining stars. Venus, for example, is frequently called the \u201cEvening Star\u201d or \u201cMorning Star\u201d because of its amazingly bright appearance at dawn and dusk. Jupiter and Mars can also appear very bright – in fact, Jupiter may even cast faint shadows, albeit in very dark conditions.<\/span><\/p>\n

Stars vary in brightness, but generally, they\u2019re dimmer than the planets that are visible to the naked eye. Some stars also show subtle colour differences, including blue, white, yellow, orange, or red, depending on their temperature. Planets also have colour, but it\u2019s usually less vibrant. That said, Mars often appears reddish, while Saturn may show a golden hue through binoculars or a small telescope.<\/span><\/p>\n

Position and Movement<\/span><\/h3>\n

Stars form fixed patterns in the sky – what we call constellations<\/a> – that remain relatively unchanged night after night. They move as a group across the sky due to Earth\u2019s rotation, but their relative positions remain stable.<\/span><\/p>\n

Planets, however, are constantly on the move. The word \u201cplanet\u201d comes from the Greek <\/span>plan\u0113t\u0113s<\/span><\/i>, meaning \u201cwanderer\u201d, because planets change position relative to the stars. They travel along a path in the sky known as the ecliptic<\/a>, which means you\u2019ll usually find them in or near the zodiac constellations<\/a>.<\/span><\/p>\n

Over days and weeks, you can watch planets shift their positions against the starry background. Occasionally, you might even witness a planetary conjunction, when two planets appear close together in the sky.<\/span><\/p>\n

Apparent Size and Shape Through a Telescope<\/span><\/h3>\n

If you have access to a telescope, the distinction becomes way clearer. Stars still appear as tiny points of light no matter how much you zoom in – they\u2019re simply too far away. But planets will start to appear as small discs. With a good telescope, you can even spot Jupiter\u2019s moons, Saturn\u2019s rings, and the phases of Venus.<\/span><\/p>\n

When and Where to See Planets<\/span><\/h2>\n
https:\/\/youtu.be\/rMQ5Yc6pJak?si=7ZhKHY0RyrW5AXVP<\/a>