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Betelgeuse: Earth’s future second Sun?

Betelgeuse is around 20 times the mass of our Sun.

Betelgeuse is a red supergiant star 640 light years away from Earth. If it were where our Sun is, its surface would reach beyond the Asteroid Belt. It’s the ninth brightest star in our skies, viewable as a distinctive red dot even in urban areas. It’s also very young, yet despite being a relatively new addition to the celestial family at 10 million years old, Betelgeuse is about to die. When it does, we’re in for one of the most dramatic light shows our world has ever seen.

Despite being 640 light years away, the Betelgeuse supernova will be so bright it will turn the night sky into twilight and, for at least a few weeks, the daytime sky will feature an extra, smaller version of the Sun.

Incredibly, even though this explosion – one of the biggest the universe can yield – will light up our sky over 6,000 trillion kilometres (3,700 trillion miles) away, 99 per cent of the energy released will be in the form of neutrinos. The Betelgeuse supernova will first bathe the Earth in these subatomic particles, which are neutrally charged and will not affect us, before the light from the blast reaches us.

Fortunately, the Earth is too far away for the deadly shockwave, heat and radiation from the cosmic explosion to cause any harm. However, though Betelgeuse could blow tomorrow, the window scientists have given for the event is 1 million years, so the odds of it happening in your lifetime are quite slim.