stars Archives - Page 9 of 10 - The Spacewriter's Ramblings

Bullets in the Orion Nebula, courtesy Gemini Observatory — "Bullets" in the Orion Nebula, courtesy Gemini Observatory

For those of you (family AND friends) who wonder what I do sometimes, this picture is where I spent some of my time the past few days. It’s an image of wakes created by supersonic-speed “bullets” of gas boring through a starbirth region in the Orion Nebula. It was taken at Gemini Observatory North on Mauna Kea in Hawai’i, using a laser guide star-equipped adaptive optics system to help remove the effects of atmospheric turbulence. (You can read more about this system here.)

I work with Gemini Observatory as a writer and I am the associate editor for their twice-a-year GeminiFocus magazine. When their public affairs office sent me this image last week, I started immediately working on some language for a press release, along with Peter Michaud (their Public Affairs Officer). It was a whirlwind of activity, involving the two of us, several scientists, and astronomerTravis Rector (University of Alaska at Fairbanks), who did the major work on the image. We worked on the language over the weekend and went through several iterations of the language. Finally the directors of the observatory gave their blessing on the version you can see here.

For me, the project entailed doing a little bit of a literature search to see just when these “bullets” were first discovered (1983, defined in 1992), and then figuring out how much of the science background was relevant to put in the story. Peter and I swapped several versions via email and chat, then sent the story on to one of the scientists (Tom Geballe) for a sanity check. Another scientist, Michael Burton of the University of New South Wales in Australia, had done some work on the bullets a few years back, and his advice was also thrown into the mix. In addition, we had Gemini astronomer Scott Fisher and Jean-Rene Roy, Deputy Director and Head of Science, look it over as well. (It’s always best to have as many eyes as possible look these things over before they go out.) By late yesterday (Wednesday, March 21), we had a version we could all live with. It went to the webmaster in Hilo, who posted the final version late last night.

It’s a lot of fun to work with these stories “behind the scenes” and talk with the people who are doing the research in the areas the Gemini images cover. Hope you enjoy the image and story!

Since it’s snowing like mad and the wind is blowing like a banshee here (and the temperature is a toasty 21 degrees Fahrenheit) right now, I want to talk about hot stars. Specifically, let’s talk about hot, dying stars that were once like the Sun. Here’s NGC 2440 to help me take my mind off the cold weather! (For you folks in sunnier climes, count your blessings!)

So, NGC 2440 first came to my attention back when I was working on my first book with Jack Brandt, called Hubble Vision. We wanted to show a nice array of stars at different stages in their lives. Star lives, by the way, are way longer than ours, but like us, they proceed in stages. There’s the infancy part—that takes place in a cocoon of gas and dust. Then, there’s the “living” part, where the star consumes nuclear fuel in its core for some amount of time. Then, there’s the old age part, where the star starts to lose mass in huge quantities and finally gives up the ghost. If the star is massive (like more than 8 or 10 times the mass of the Sun), then it sheds lots of its atmosphere before blowing itself to smithereens in a supernova explosion.

If the star is like the Sun, then it litters its environment with material that it blows away from itself. It does it maybe once, or maybe several times, creating shells of gas (nitrogen, hydrogen, oxygen, and helium, for example). That “exhaled” matter forms a shell around the star. Then, the interior star contracts (shrinks), and in the process, heats up.

So, NGC 2440 (what’s left of it) is very hot—like 400,000 degrees Fahrenheit (try more than 400,000 times hotter than your oven gets). All that heat has to go somewhere and do something, so it’s lighting up the huge cloud of mass that the star lost earlier in its life.

There was more than one outburst from NGC 2440 during its old age, which is why we see two “lobes” of material surrounding the central star.

If you want to see a huge version of the image above, go here (the HST news center). The highest-resolution image almost looks three-dimensional.

Now, I feel a bit warmer. How about you?

The Spacewriter's Ramblings

Category Archives: stars

Speeding Through the Universe

Warming Your Hands at The Fire of a Dying Star

Exploring Science and the Cosmos