Bad Astronomy

The Serpent’s Teeth

In the southern skies lies the constellation of Serpens, the Serpent. It’s a big constellation, covering quite a bit of sky, so you’d expect there to be interesting objects in it. Not only that, it covers territory that includes a thick part of the Milky Way’s disk, where we see lots of goings-on, including stars that are born, stars that die, stellar nurseries, and more.

In fact, Serpens has in its borders one of the nearest factories in the sky that is churning out stars. It’s located very roughly 1000 light years away, close enough for us to study it in detail. The problem is, the place is so littered with thick dust – and young stars are enshrouded in it after they are born – that it’s impossible to get good visible light images of the infant stars there.

Enter Spitzer Space Telescope. It sees infrared light, which pierces the dust. Young stars are also bright in the infrared, making them perfect targets for Spitzer. Like so:

This spectacular image shows young, bright stars pouring out infrared– stars which are essentially invisible in optical images. In this false color image, hot hydrogen gas shows up as green, and you can see it formed into sheets and blobs; the stars emit gas in beams which slam into the surrounding cooler gas. The overall red/pink glow is due to what are called polycyclic aromatic hydrocarbons, or PAHs. You might call it soot. They really are long-chain organic molecules that are extremely dark, but are copiously produced near young stars and emit infrared when warmed.

Astronomers weren’t sure if this little cluster was forming on its own, or was part of the overall Serpens star forming region, but follow-up observations using even longer wavelengths (submillimeter, basically short-wave radio) indicated the gas was associated with the gas in the star-forming region as a whole. So this little family is part of the bigger clan of stars being born there.

Isn’t it nice when we can get a beautiful family portrait like this one?