You ever see those freaky contrails in the sky and wish you’d seen the whole launch?
A few years ago I decided to never miss another launch again. So I signed up for the Launch Alert. And tomorrow morning, bright and early there’ll be another show and the weather looks to be perfectly cooperative. So haul yourself outta bed tomorrow morning at three!
The launch of NASA’s Aura atmospheric chemistry satellite from Vandenberg AFB has been delayed 48 hours due to a technical problem with the booster. The spacecraft is now scheduled to lift-off from Space Launch Complex 2 West aboard a Delta II rocket on July 13 at the start of a launch window that extends from about 03:01:57 to 03:04:57 PDT (10:01:57 to 10:04:57 UTC).
The rocket will rise vertically for several seconds before it begins to head south. If the Delta functions normally, Aura will be inserted into a 438-mile-high (705 km) circular orbit inclined 98∞ to the equator.
Once Aura becomes operational, it will observe the portion of the atmosphere between the Earth’s surface and a height of 50 miles (80 km). The craft’s advanced instruments will measure atmospheric temperature and the concentration of selected gases and aerosols. Information from the spacecraft could answer a variety of questions including if the ozone layer is recovering, which processes control air quality, and how the Earth’s climate is changing.
Since the launch occurs before dawn, it could be visible for hundreds of miles – perhaps as far away as portions of Nevada, Arizona, and Mexico. Just before liftoff, the Delta’s first stage main engine and several strap-on solid fuel rocket motors will ignite. Observers may see a flash on the horizon from the direction of the pad, a few seconds of darkness, and then a rising orange orb or “star”. The brightness and color of the Delta at this point will be due to the solid fuel motors’ brilliant orange flames.
Two events to look for during the first stage burn are the jettison of the solid rocket motors. The spent motors will still be burning and will flash as they tumble during free-fall. Six rocket motors will be jettisoned about 1 minute 27 seconds after launch followed by three more at about T+ 2 minutes 12 seconds. These events should be visible to the naked eye for a distance of at least 100 miles (161 km).
After solid motor jettison, the liquid-fueled first stage main engine will continue to power the Delta II. Since liquid fuel engines produce a dimmer flame than solid fuel motors, the Delta will drop in brightness.
Observers in dark locations may see the Delta’s first stage exhaust plume take on an elongated or jellyfish-like appearance as it expands at high altitude. At about T+ 4 minutes 24 seconds the first stage main engine will cut-off and the vehicle will disappear into the darkness as it heads downrange.
Information Courtesy of Launch Alert (www.spacearchive.info/newsletter.htm). Reprinted with permission. (Thanks Brian Webb!)