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For most of its life, a star like the Sun looks a bit drab — it’s a bright, glowing orb that doesn’t change much. At the very end, though, the star puts on a spectacular show. It expels its outer layers of gas into space, forming a colorful bubble that can be sculpted into many different shapes. The bubble can last for thousands of years before it dissipates and fades from sight.
One of the best-known examples stands high in the southeast as darkness falls, in Vulpecula, the fox.
The bubble is known by several names. The most evocative is the Dumbbell Nebula; seen through a telescope, it resembles a hand weight like you’d use at the gym.
The best measurements say the nebula is more than 1200 light-years away. The distance could be off by a couple of hundred light-years in either direction, though.
For most of its life, the star was like the Sun, steadily burning through the nuclear fuel in its core. Now, though, it can no longer sustain the nuclear reactions, so it’s shut down.
In response, the star’s outer layers began streaming into space more than 10,000 years ago. The gas left the star in waves and clumps, producing shells of gas with embedded “knots” that can be heavier than Earth.
Although the core is no longer producing nuclear reactions, it continues to shine because it’s extremely hot. Its energy causes the escaping outer layers to glow, setting the Dumbbell ablaze with color — a brilliant final act for a star.
Script by Damond Benningfield