Rocket Science

Something strange soars over San Diego skies, and people all over the West wonder what it may be.

Staff Writer Clara Scheidle

Photographs by Clara Scheidle

photo of the mysterious celestial object

As the sun set on Dec. 22nd, something mysterious rose out of the hills in Southern California. Illuminating the sky with a bright white plume of smoke, the UFO suddenly changed directions, and the trail became more of an ominous, glowing orb. Then, as if things couldn't get any stranger, as the thing moved across the sky a piece of it appeared to fall off and descend towards Earth while the rest of it continued southward on its path, before disappearing on the horizon. The detached piece fell downwards before appearing to catch fire and vanish into thin air.

Witnesses from Colorado all the way to San Diego and even further south in Mexico were baffled at just what the strange object could be. People on their way home from work pulled their cars over just to get a better look as it passed overhead. Crowds gathered on sidewalks and storefronts as people abandoned their previous tasks to get a better view. And when it disappeared, everyone asked the same question.

What was that?

Though various theories and suspicions were quickly thrown around, the Unidentified Flying Object was quickly identified as a rocket launched by SpaceX at the Vandenberg Air Force Base, which is located in California and is in rather close proximity to Los Angeles.

Viridiana Preciado, a student at UH Hilo who was home for the holidays, witnessed the event. She was getting her hair cut in a salon in Tijuana, Mexico, when the rocket flew overhead. She, like so many others, was completely unaware that the launch was going to take place that particular evening, and could only guess at what it was.

“It took me by surprise,” she says simply. “I thought it was going to be something from the [military bases] because these events have happened in the past, but above all I assumed it to be with a space organization.”

The rocket contained ten low orbiting satellites which belong to a private commercial company called Iridium. This particular satellite is the latest addition to their NEXT s ystem. These satellites are the fourth group of 10 which have already been successfully launched and deployed since June 2017. They are only 10 of 81 satellites included in the system- 75 of which will be launched by SpaceX, who are determined to complete the task by the middle of 2018. SpaceX states that the satellites will offer a “next generation communications platform.”

Preciado comments on this, saying, “I think [this is] a step in advancing our technology and [developing] a better understanding of our universe, which I think will turn people to more attention to scientific news.”

But doesn’t having 81 of them seem a bit excessive? Are they all really necessary?

As it turns out, they are. All 81 satellites will work together in a fundamental way to make sure that communications around the globe won’t ever come to a random halt. John Hamilton, a professor of astronomy and physics at UH Hilo, states that, “You need 81 of them so you can have better coverage [because] they move over the land very fast, [unlike] a TV satellite, which is in geosynchronous (much farther away) but stays over you so you can use it all the time. These lower ones move fast, so they cross the horizon very fast, so you need another one by the time one sets, the other one has to come over.” According to Hamilton, this is very similar to the way GPS satellites work.

For those out there who are not well versed in astronomy or physics, there are still two events that remain unexplained: why did the rocket create such a bizarre, oblong plume of smoke and why did parts of the rocket detach?

Part of the beauty formed by the smoke from burning fuel has to do with the timing of the launch. “What occured in LA is that the very high altitude and the sun angle- the sun was setting- made it so that the upper atmosphere was still lit, but it was dark out, so it showed this really wide contrail.” The contrail itself was abnormal, as people can usually witness ones that go in a straight line in broad daylight. Hamilton clarified that this happens because in lower altitudes, air pressure acts as a constraint to the plumes, whereas in higher altitudes, and therefore lower air pressures, the rocket plume will spread out, as seen by so many that night.

“Things like that happen in Hawai`i, when they launch things off the Barking Sands Pacific Missile Range,” Hamilton discloses. “Occasionally, they’ll do atmospheric explosions. They’re really big because of high altitude, and typically are done near sunset.”

Although detaching pieces of rocket and letting them descend back to Earth may seem like a counter intuitive idea, it is actually the most effective way to launch anything into space. It takes a great deal of energy to escape Earth’s gravity, so the best and most efficient way to do so is to have a multi- stage rocket.

“That’s the rocket’s first stage,” Hamilton continues. “Once they’re done with their fuel, which is 90% of the weight of that rocket, they jettison that part because they don’t need it anymore- it just adds mass for the remaining fuel- so they get a bigger [boost].” Basically, less mass is easier to carry out into space, therefore letting unuseful pieces come off makes the entire system more efficient. This is actually a problem that anyone taking PHYS 170 Gen Phys I: Mechanics (4) at UH Hilo will eventually learn how to tackle- after all, “physics is rocket science,” Hamilton jokes.

Although the theories that were jumping around Twitter and Instagram that night were entertaining to view and then later to joke about, it doesn’t change the fact that the now identified flying object will be changing the world in other ways. “[The satellites] are being geared toward bringing internet to the whole world,” Hamilton confirms. “So it’s a good thing.”