Bad Astronomy

Alphas in the heart of the Omega

After having recently posted an interesting picture of the results of star formation in a nearby galaxy, here’s another example, but far closer: an incredibly detailed image of the heart of the Omega Nebula, where stars are being born from huge clouds of gas and dust:

[Click to ennebulenate, or grab an even bigger version.]

This image was taken using the 8.2 meter Antu telescope, one of four making up the European Southern Observatory’s Very Large Telescope in Chile. What you’re seeing here is the central region of a much larger complex of gas and dust located about 6500 light years away toward the center of our galaxy. The whole thing is about 20 light years across, and perhaps as many as 1000 stars are in the process of being born or were recently formed there.

The red color is due to the presence of warm hydrogen gas, the basic building material of stars. It’s being lit up and is glowing due to very young, massive and hot stars – the alpha dogs, if you will – flooding the nebula with ultraviolet light. The dark material is actually dust, which is opaque in visible light, so it blocks the glow from material behind it.

That dust really caught my eye: some of it is not shapeless and random, but has been sculpted into very long, very thin wisps and tendrils. Most of these are parallel, which is a big clue to what causes them. They are most likely being shaped this way by shock waves; supersonic material blasted out from those same young, hot stars. These powerful stellar winds of subatomic material race out and slam into the surrounding material, compressing it. Waves from various stars can also collide, creating very thin streamers like this. Some are so narrow they’re barely resolved in the picture at all.

The Omega Nebula is a big, bright cloud that’s easy to spot in the summer sky; I observed it countless times as a kid with my telescope. If I can spot it with my amateur equipment, that means that big ‘scopes really see fine details. But they also can give us deep, spectacular overviews as well; the inset image here is from the redundantly-named Very Large Telescope Survey Telescope (VST to its friends) showing far more of the region. The first picture above is just a teeny bit of this one; click to embiggen it.

And even this isn’t the whole schmeer; the Spitzer Space Telescope got an image of all this plus even more of the interstellar material located nearby. That volume of space is huge, and it’s a complete mess!

But it’s certainly lovely. The scientific aspects of these sorts of surveys are obvious enough – learning about how stars form and how they affect their environment is a key part of understanding the whole cycle of stellar life – but there is an obvious beauty to it as well. In fact, the first image was taken as part of Cosmic Gems, an educational program to help foster and increase an understanding of astronomy and science in the public… and that, for me, is the alpha and omega of what I do, too.

Image credit: ESO; ESO/INAF-VST/OmegaCAM. Acknowledgement: A. Grado/INAF-Capodimonte Observatory; ESO/INAF-VST/OmegaCAM. Acknowledgement: OmegaCen/Astro-WISE/Kapteyn Institute