A picture can make all the difference when sharing the wonders of spaceflight, astronomy and planetary science.
For that reason, The Planetary Society’s new website places a much larger emphasis on the “pretty pictures” out there waiting for citizen scientists to discover and process. Emily Lakdawalla talks about this in her recent guest blog entry for Nerdist, and also has a great how-to article for creating your own images from raw spacecraft data.
I wanted to get in on the fun, so I added a new feature to my own blog: full-size, moveable images. A lot of my articles are about space vehicles, and there’s nothing like a giant photo to capture the glory of a launch.
First up, one of my favorite launch photos: a Delta IV Heavy rocket that happens to be ON FIRE.
I love D4H. The rocket consists of three ungainly liquid-fueled booster cores strapped together, making it look like someone literally took three rockets and tied them altogether. But that’s not why I love it. The D4H’s most alluring feature is, in my opinion, its ability to set itself on fire. This is actually true of all Delta IV series vehicles.
Here’s what happens: right before ignition, a lot of hydrogen gas gets dumped through the D4H’s RS-68 engines. This primes the engines for ignition, just a few seconds prior to the introduction of liquid oxygen. The result is a lot of excess hydrogen gas floating around the base of the rocket, which becomes a serious explosive hazard. The launch pad has several spark generators that intentionally ignite the hydrogen to burn it off, preventing what would be akin to a car backfiring. The burning hydrogen gas attaches itself to the rocket’s lower exterior, which is heavily insulated. The insulation, in turn, burns and smolders as the rocket rises.
All of this is completely normal, and makes for a spectacular scene. Click the image to pop open a full-resolution, moveable image. Close out of it by pressing your escape key.
Excess hydrogen gas ignites and burns the insulation of a Delta IV Heavy rocket as it lifts off on January 20, 2011. Credit: United Launch Alliance
The second picture I want to show you is a color composite I made of Saturn and Titan, using raw data from the Cassini spacecraft. I followed Emily’s above-mentioned how-to article to create this.
My only difficulties came from figuring out how to get the filtered red/green/blue images into each color channel for a stacked composite. Here’s a quick procedure I found with some Google searching that worked for me:
- Save the three raw Cassini images to your computer. Make sure you grab a matching red, green and violet/blue set. Also, it helps to change the filenames to keep them straight.
- Open all three images in your graphics program (I use Photoshop).
- Create a new image with the same dimensions as your individual images. Open your channels window, where you can select the red, green and blue channels individually.
- Select and copy the contents of one of your red, green or blue images.
- In your new image window, select the corresponding red/green/blue channel and make sure the other channels are hidden. Paste your image, and repeat the process for the other two channels.
- Once you have pasted all three channels individually, you can view them all together to get the color image. Then you can align the stack, cut out foreground objects, and clean up blemishes.
Here’s my result:
Color composite of Saturn and Titan, as captured by the Cassini spacecraft on May 6, 2012. Credit: NASA/JPL/Space Science Institute, processed by Jason Davis
Thanks very much to the folks that created the Auto ThickBox Plus plugin for WordPress.
