WHEN you look up at a nights sky, some stars may look like they twinkle blue or red.

These red-hued specks are red dwarf stars, also called M-dwarfs.

Getty

What are the red stars in the sky?

Here’s a full list of the brightest red stars that can be seen in the night sky with the naked eye, binoculars or a telescope.

These can be found anywhere from Taurus and Sagittarius constellations, to Orion and Canis Major.

• Arcturus
• VY CMa
• Mu Cephei
• RW Cephei
• VV Cephei A
• Gacrux
• WOH G64
• Rasalgethi
• Betelgeuse
• S Persei
• VX Sagittarii
• Antares
• UY Scuti
• 119 Tauri
• Aldebaran

Antares is often confused with Mars because of its colour.

Why do some stars in the sky look red?

The reason stars look different colours – some being red or blue – is due to their temperatures.

Red stars are cooler than blue stars.

The cooler the star, the longer the wavelength of light it will emit.

Cooler stars are red or a reddish-brown, which are longer wavelengths.

While the hottest ones are blue or blue-white, for their shorter wavelengths of light.

Are red stars rare?

Red dwarf stars are not rare.

They are actually considered to be the most common type of star in the universe.

They are the most common type of star in our galaxy, making up more than 75 per cent of the 200billion stars in the Milky Way, according to Nasa.

While they are born in much greater numbers, astronomers also believe red stars to live as long as trillions of years.

This means that some red dwarfs have been around for almost the entire age of the universe.