Cosmic butterfly flaps its wings in stunning detail

This serene scene is anything but, as the death dance of a pair of stars sends hot gas out into space.
By | Published: September 9, 2020 | Last updated on May 18, 2023
The butterfly-shaped planetary nebula NGC 2899
As Sir Elton John sings in “Someone Saved My Life Tonight,” “Butterflies are free to fly, fly away …” He probably wasn’t thinking of this cosmic butterfly.
The butterfly-shaped NGC 2899 appears to soar through the vacuum of space in a recent image captured with the European Southern Observatory’s Very Large Telescope. But this cosmic bubble of gas, located between 3,000 and 6,500 light-years away, isn’t as serene as the winged insect it resembles. In reality, this planetary nebula was produced by the death of one of two stars astronomers suspect lie at its center.

Astronomers believe one of the two stars shed its outer layers at the end of its life, while the other now dances through the flow of gas from its neighbor, creating this stunning space butterfly. The gas extends up to two light-years from the nebula’s center, glowing against the backdrop of in from the Milky Way. This gas can reach temperatures of more than 10,000 degrees, thanks to radiation from the parent stars buried within.
Not every planetary nebula looks like NGC 2899, though. Its so-called bipolar, or two-lobed, shape only occurs in about 10 to 20 percent of nebulae — likely those with two stars. Other planetary nebulae typically resemble a disk, ring, or sphere.

Tour some of the sky’s most stunning planetary nebulae with Astronomy columnist Stephen James O’Meara.