Messier 17: Could a massive cosmic rose smell as sweet by any other name?

A spectacular nebula, Messier 17, rapidly churns out newborn stars that create its distinctive rosy glow.

ESO
This image of the rose-colored star forming region Messier 17, released Sept. 23, 2015, was captured by the Wide Field Imager on the MPG/ESO 2.2-meter telescope at ESO's La Silla Observatory in Chile. It is one of the sharpest images of entire nebula. It not only reveals its full size but also retains fine detail throughout the cosmic landscape of gas clouds, dust and newborn stars.

"A rose by any other name would smell as sweet," said Juliet. Does that still apply if the rose is a giant cloud of gas and dust?

Officially named Messier 17, this spectacular nebula is now visible in stunning relief in a newly released photo from the European Southern Observatory's La Silla telescope in Chile.

The rose-hued stellar nursery has earned many colorful nicknames, including the Omega Nebula, the Checkmark Nebula, the Horseshoe Nebula, the Lobster Nebula, and the Swan Nebula. Whatever you call it, Messier 17 remains a gigantic hotbed of star-birth – one of the youngest and most active in our galaxy. Astronomers have counted nearly 800 young stars emerging in its center, with even more stars scattered across the whole nebula. 

You can see Messier 17 in the constellation Sagittarius (The Archer), where the cosmic rose stands out as particularly bright against one of the darker regions of the Milky Way. It stretches 15 light years across and its gas has more than 30,000 times the mass of the Sun, astronomers estimate. 

What gives this stellar nursery, located 5,500 light-years from Earth, its rosy hue? Glowing hydrogen gas.

Infant stars emit ultraviolet light that excites the hydrogen gas around them. That excited gas radiates in the pink to red wavelengths, bright enough to catch astronomers' eyes.

Messier 17's official name comes from Charles Messier, a French astronomer who searched the sky for comets. As he hunted, Mr. Messier also noted the locations of bright celestial objects that were not comets, so he wouldn't be confused. He numbered the radiant objects in his published astronomical catalog in 1764.

But Messier wasn't the first to spot the spectacular rosy nebula. Swiss astronomer Jean-Philippe Loys de Chéseaux had found the cosmic rose around 1745, but his work was not widely publicized, so when Messier independently discovered the same nebula later, the Frenchman received the credit.

Messier 17's many nicknames come from its appearance, which reminds some of the Greek letter omega, while to others it looks like a swan, a horseshoe, or a lobster. 

The glow of this vast celestial rose is interrupted by darker spots and webs, caused by dust that blocks the light from the excited hydrogen gas.

Increasingly powerful telescopes have allowed astronomers to see more and more colors hidden in the nebula. When the ESO took a closeup six years ago, astronomers described a "fascinating palette of subtle colour shades across the image," caused by "different gases (mostly hydrogen, but also oxygen, nitrogen and sulphur) that are glowing under the fierce ultraviolet light radiated by the hot young stars."

You've read  of  free articles. Subscribe to continue.

Dear Reader,

About a year ago, I happened upon this statement about the Monitor in the Harvard Business Review – under the charming heading of “do things that don’t interest you”:

“Many things that end up” being meaningful, writes social scientist Joseph Grenny, “have come from conference workshops, articles, or online videos that began as a chore and ended with an insight. My work in Kenya, for example, was heavily influenced by a Christian Science Monitor article I had forced myself to read 10 years earlier. Sometimes, we call things ‘boring’ simply because they lie outside the box we are currently in.”

If you were to come up with a punchline to a joke about the Monitor, that would probably be it. We’re seen as being global, fair, insightful, and perhaps a bit too earnest. We’re the bran muffin of journalism.

But you know what? We change lives. And I’m going to argue that we change lives precisely because we force open that too-small box that most human beings think they live in.

The Monitor is a peculiar little publication that’s hard for the world to figure out. We’re run by a church, but we’re not only for church members and we’re not about converting people. We’re known as being fair even as the world becomes as polarized as at any time since the newspaper’s founding in 1908.

We have a mission beyond circulation, we want to bridge divides. We’re about kicking down the door of thought everywhere and saying, “You are bigger and more capable than you realize. And we can prove it.”

If you’re looking for bran muffin journalism, you can subscribe to the Monitor for $15. You’ll get the Monitor Weekly magazine, the Monitor Daily email, and unlimited access to CSMonitor.com.