Thursday, July 10, 2014

Delta II Rocket Image Sequence from OCO-2 Launch

Four minutes during NASA's OCO-2 satellite launch from Vandenberg AFB, California
NASA sent the OCO2 satellite up on a Delta II rocket last Wednesday morning, and I captured it on several different cameras at once.

+Philip Plait (The Bad Astronomer) goes into some detail on the satellite in his blog posNASA Launches a New Eye on Carbon Dioxide, so I'll stick to the photographic detail in the following sequence of photos matched to their corresponding events in the launch timeline.

2:55:53 a.m.
T-minus 30 seconds. SRB ignitors will be armed at T-minus 11 seconds.

The launch ignition sequence will begin at T-minus 2 seconds when a launch team member triggers the engine start switch. The process begins with ignition of the two vernier thrusters and first stage main engine start. The three ground-lit solid rocket motors then light at T-0 for liftoff.
2:56:23 a.m. 
LIFTOFF! Liftoff of the Delta 2 rocket with the Orbiting Carbon Observatory 2 to watch the Earth breathe from space!
T+plus 15 seconds. The launch vehicle is departing Vandenberg Air Force Base, heading south for the trek downrange over the Pacific carrying the OCO 2 spacecraft.

T+plus 36 seconds. Delta has broken the sound barrier, rapidly accelerating on the power of its first stage main engine and the three ground-lit strap-on solid-fuel boosters.
2:57 a.m. 
T+plus 50 seconds. The rocket has flown through the area of maximum aerodynamic pressure in the lower atmosphere.

2:57 a.m. 
T+plus 1 minute, 6 seconds. All three ground-start solid rocket boosters have burned out. The Delta 2's first stage RS-27A main engine is providing the sole thrust for the next couple of minutes.

2:58 a.m.
T+plus 1 minute, 50 seconds. The ATK-made solid rocket boosters have jettisoned from the first stage. They remained attached until the rocket cleared off-shore oil rigs.

T+plus 2 minutes. Delta now weighs half of what it did at liftoff two minutes ago.

2:59 a.m.
T+plus 2 minutes, 41 seconds. Delta now traveling at Mach 5.
T+plus 3 minutes. The first stage main engine still firing well. The Aerojet Rocketdyne powerplant consumes kerosene fuel and liquid oxygen to produce about 237,000 pounds of thrust.
3:00 a.m. 
T+plus 3 minutes, 34 seconds. The Delta 2 is now passing a speed of Mach 10.
3:01 a.m.
T+plus 4 minutes, 39 seconds. MECO. The first stage main engine cutoff is confirmed and the spent stage has been jettisoned.
T+plus 4 minutes, 44 seconds. The Delta's second stage has ignited! The engine is up and running.
T+plus 4 minutes, 51 seconds. The rocket's nose cone enclosing the satellite payload has been jettisoned.

3:02 a.m.
The rocket is at an altitude of 82.7 nautical miles, a downrange distance of 360 nautical miles and a velocity of 11,127 mph.

Here's NASA's diagram of the sequence (click on it  for a much larger view):

Here's the whole sequence put together in a time-lapse video covering 3 hours prior to 1 hour after launch:

If night photography looks like something you'd like to master, I'm scheduling a night photography session at California's Bodie State Historic Park on July 25:

Digital photography differs from film photography in many important respects, and nowhere is that more true than for night photography.  I've invested the sleepless nights learning the techniques and trade-offs to save you time and money required to discover it all for yourself.