Neil's News

Delta IV Heavy

21 January 2011

Yesterday a couple of coworkers and I drove down to Vandenberg Air Force Base to watch the first west-coast launch of the Delta IV Heavy. This is the tallest rocket currently in use (only the Saturn V and N1 were taller) and is used exclusively by the US military for launching spy satellites. These spacecraft are essentially billion dollar copies of the Hubble Space Telescope, except they are turned around 180° to look at Earth. The US has "many" of them. As of today, the US has one more. Here's the official launch video:

I've watched hundreds of launches on TV and streamed live over the Internet. In terms of crispness and detail, nothing beats the high-powered tracking cameras that professional broadcasters employ. However, after watching a launch in person, I noticed what was missing: sound. In real life rockets are louder, much deeper and more powerful. The rumbling sound is like nothing I've heard or felt before. Layered on top of this sound is a sporadic whip-like cracking sound. No reasonable sound system can reproduce the raw power of a rocket.

West-coast Deltas launch from the infamous "Slick Six" pad^[?]. This ocean-side location is surrounded on three sides by hills making it impossible to observe the pad itself. Therefore the first indication of launch was a low rumbling, followed 10 seconds later by the blackened rocket popping up from behind the hills. The triple-cored rocket climbed smoothly on three daggers of flame. At an altitude of about a kilometer it entered a moist layer of air and abruptly started leaving a pure white contrail. Two kilometers further up the contrail ended as abruptly as it began. The rocket pitched over and (from our vantage point) disappeared into the Sun.

A short while later it reappeared on the other side of the sun, this time in two distinct pieces. This was a bit confusing, since there should have been three pieces; the two spent boosters and the core. Either one piece was eclipsing a second, or booster jettison happened in the sun and we were witnessing the second stage separation.

Long after the rocket had disappeared from view its rumbling was still audible -- Doppler shifted sound waves generated minutes ago in the tenuous reaches of the upper atmosphere, racing downwards at 20 kilometers per minute.

We explored the perimeter of the base fairly extensively and found what we believe to be the best location from which to watch. It is five miles east from the pad and offers a face-on view of the triple core rocket. By contrast, the suggested public viewing location is twelve miles north from the pad, would see the rocket edge-on, and is in the opposite direction of flight. Another promising location is Jalama Beach, but the road to it was completely closed for safety reasons.

View Vandenberg Launch in a larger map

This excursion was definitely worthwhile and was a lot of fun. Here are our launch photos.

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Why is it important to choose good passwords? Here's a snippet of the authentication log from my web server. Machines in China are pounding away, 24/7 guessing usernames and passwords.

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