Hubble Revisits an Icon

SCIENCE

Teachers, scroll down for a short list of key resources in our Teachers’ Toolkit.

Discussion Ideas

Why do you think astronomers have nicknamed this part of the Eagle Nebula the “Pillars of Creation”?
- Pillars . . . The long clouds of cosmic dust look like pillars. Pillars, also called columns, are vertical structures used for support or decoration.
- . . .of Creation . . . New stars are being created inside the pillars’ dusty swirls.

Why is the “Pillars of Creation” name a little misleading?
- Pillars . . . Pillars are vertical, but concepts like “vertical,” “horizontal,” “up,” or “down” don’t have a lot of meaning to astronomers because there is no standard frame of reference in outer space. (We even flip images to have them conform to what we think space should look like!) Here is a beautiful view of the Eagle Nebula with the Pillars of Creation offset just a little. Here’s another. There’s no wrong way to look at this!
- . . . of Creation . . . According to the Nat Geo article, “though these are known as the pillars of creation, astronomer Paul Scowen notes that they’re also regions of destruction. ‘The ghostly bluish haze around the dense edges of the pillars is material getting heated up and evaporating away into space.'” Watch this hangout to learn more from Dr. Scowen about the new images, Hubble, and stellar nurseries.

Compare these two images of the Pillars of Creation. The new-and-improved image on the right looks a little different than the still-beautiful original on the left. The images were taken by the same camera, using the same visible-light filter, of the same region of the sky. Why do you think the photos look different?
- The newer photo is much sharper, meaning it offers much more detail the the original.
- The newer photo also has a wider field of view, meaning it displays a greater angular area. Astronomers combined several exposures to show the wider field of view.

The good folks at NASA and the European Space Agency actually released two versions of the new image: one taken using visible light and one using near-infrared light. Both visible and near-infrared light (radiation) are part of the electromagnetic spectrum, which ranges from long, low-frequency radio waves to short, high-frequency gamma rays. Of visible or infrared, which wavelength is longer, and has lower frequency? Take a look at our illustration for some help.
- Infrared light has longer, more low-frequency waves than visible light.

How did astronomers take a color photo using visible light? (It’s not as simple as it seems!)
- According to Hubble’s Color Toolbox: “Hubble’s cameras record light from the universe with special electronic detectors. These detectors produce images of the cosmos in shades of black and white. Finished color images are actually combinations of two or more black-and-white exposures to which color has been added during image processing. The colors in Hubble images, which are assigned for various reasons, aren’t always what we’d see if we were able to visit the imaged objects in a spacecraft. We often use color as a tool, whether it is to enhance an object’s detail or to visualize what ordinarily could never be seen by the human eye.” So, although the image was taken in the visible-light part of the spectrum it probably isn’t quite what our eyes would see.
- Here’s how astronomers colored the 1995 image. Ionized oxygen is represented in blue, sulfur in orange, and hydrogen and nitrogen in green.

How did astronomers take a photo using infrared light?
- According to Hubble, “For the near-infrared image, astronomers used filters that isolate the light from newly formed stars, which are invisible in the visible-light image. At these wavelengths, astronomers are seeing through the pillars and even through the back wall of the nebula cavity and can see the next generations of stars just as they’re starting to emerge from their formative nursery.”

Could astronomers provide even more versions of the Pillars of Creation image, using different parts of the electromagnetic spectrum?
- Of course! Here’s a beautiful image of the Eagle Nebula, taken in the X-ray part of the spectrum, for instance. (The Pillars of Creation are at the bottom center-left.) X-rays see through the nebula’s dusty columns just like they see through our own flesh—learn more about X-rays here.
  The image was taken by the good folks at Chandra, NASA’s “flagship mission for X-ray astronomy.” (What Hubble is to visible light, Chandra is to X-rays!) Because they’re such good folks, they even put the image into visible-light perspective—click here.
  Photograph by NASA/CXC/U.Colorado/Linsky et al.
How “new” is the subject of the new Pillars of Creation image?
- About 6,500 or 7,000 years—that’s how long it takes light from the Eagle Nebula to reach Earth.

Blow-Your-Mind Bonus: Did NASA just release photos of something that doesn’t exist?
- Probably. Most astronomers think the Pillars of Creation aren’t there anymore, that they’ve been obliterated by a supernova. (Awesome.) However, “we won’t be able to capture photos of the destruction for another 1,000 years or so.” Stay tuned.