Ramping down a super star

It’s always iffy to bestow a superlative on a star. That certainly seems to apply to the Pistol Star. It’s definitely one of the most impressive stars in the Milky Way Galaxy. But it’s probably not quite as impressive as first reported.

The star was discovered three decades ago. It wasn’t seen earlier because it’s hidden behind clouds of dust that make it appear much, much fainter.

The star is named for the outline of a surrounding bubble of gas — the Pistol Nebula. It was created by the star itself. The star is so big and hot that it’s blowing away its outer layers at a furious rate.

When astronomers first saw the Pistol, they estimated its mass at about 250 times that of the Sun. That made it the heaviest star yet seen. Since then, the star’s been studied in more detail. That’s shown that it’s only a few dozen to perhaps a hundred times the Sun’s mass. That’s heavier than all but a tiny percentage of other stars, but not quite at the top of the list.

And the Pistol may not be quite as bright as first thought, either. Estimates range from about 1.6 million to 3.3 million times the brightness of the Sun. Either way, it’s an impressive star — just not the most impressive.

The Pistol Star is in Sagittarius. The constellation is low in the south at nightfall. Some of its stars form the outline of a teapot. The Pistol Star is in the “steam” above the spout of the teapot — a brilliant star hiding at the heart of the galaxy.

Script by Damond Benningfield