1. WISE 1828+2650 – Discovered only in 2011, this brown dwarf, or failed star – just nine light years from Earth – has a surface temperature that is cooler than the human body at just 25°C (80°F).
2. Eta Carinae – The brighter component of unstable double star Eta Carinae is a blue hypergiant – perhaps the hottest star known with a temperature of 37,000°C (67,000°F).
3. VFTS 102 – The bright blue giant VFTS 102 sits 160,000 light years away in the Large Magellanic Cloud galaxy. Spinning 300 times faster than the Sun, it bulges out noticeably at its equator.
4. R136a1 – Both the brightest and the heaviest star, R136a1 lies at the heart of the Tarantula Nebula, a huge region in the Large Magellanic Cloud. It has a mass of around 265 Suns!
5. HE 1523-0901 – The oldest-known star has an estimated age of 13.2 billion years. This suggests it formed from the remains of the very first stars, about 500 million years after the Big Bang.