Southern California

Rise and Shine: SpaceX is Launching Another Rocket From SoCal

The early morning launch may set the stage for a cool display as the rocket climbs into sunlight.

SpaceX will be launching another Falcon 9 out of Vandenberg Air Force Base on Wednesday, Feb. 21.

The launch was originally set to take place Saturday, Feb. 17, but was pushed back to Sunday and then pushed back further to Wednesday to allow for final inspections. Should the launch take place early in the morning, it may set the stage for a cool display as the rocket climbs into sunlight.

Send Us Your Photos: Email isee@nbcla.com or click here

The SpaceX Falcon 9 is a two-stage launch vehicle, meaning it is made of up two parts that carry the satellite payload into orbit. The first stage is pretty visible during dusk, dawn and night launches due to the nine rocket engines that fire for the first 162 seconds of the flight.

After the main engines cut off, the second stage (upper portion of the vehicle) separates and fires a single engine to continue the flight into space. During the highly visible launch in late December, the first stage created a spiral-like pattern in the exhaust of the second stage.

This launch will be putting a Spanish satellite named “Paz” into orbit. The first stage for this mission has been used in another launch and was recovered after landing on a barge. It may be the first stage that launched FORMOSAT-5 on Aug. 24, 2017.

Most of the launches out of Vandenberg put satellites into a polar orbit, meaning that the satellites are launched toward the south. The rocket parallels the coast, increasing the visibility for many in SoCal. The launches become spectacles just after sunset, or just before sunrise, because the exhaust plume becomes illuminated by sunlight as the rocket goes higher.

Thanks to the curvature of the Earth, sunrise and sunset times change with altitude. The general rule of thumb is that for roughly every 5,000 feet of altitude, sunset or sunrise changes by one minute. So for a rocket at 40 miles up, sunset is about 40 minutes later than at the ground. As the rocket gains altitude, it will eventually be back into sunlight, which is when the exhaust plume becomes a bright cloud in the night sky.

You may notice the plume spreading out as the rocket continues its climb. This effect is caused by the decrease in air pressure as you get higher. At the surface, pressure is high enough to keep the exhaust from spreading out.

Another great example of a dawn launch was an Atlas V departing Cape Canaveral, Florida in September of 2015 with the MUOS-4 satellite. The launch occurred about 45 minutes before sunrise and was seen across much of Florida due to the brightly illuminated exhaust plume.

Contact Us