Depending on where you live on the Central and South Coasts, rocket launches from Vandenberg Space Force Base may look and sound different.
In Lompoc, which is close to the base, they're loud.
"The people who live in Lompoc hear it all the time," said Kira Abercromby, an aerospace engineering professor at Cal Poly San Luis Obispo.
Why do the launches happen at Vandenberg? It's a matter of planetary mechanics.
"The majority of spacecraft will launch in the east direction," explained Abercromby. "The Earth is already spinning, so a rocket launched east gets a little free help from that rotation. Here, there's no launching eastwards because it's over land."
Launching over land is forbidden because it increases the risk of falling debris if something goes wrong after launch.
"The ideal orbits that you can go into out of Vandenberg are directly over the poles," Abercromby continued. "It's called a polar orbit or a high inclination orbit because you can launch directly south and get directly into that trajectory," she explained.
Such orbits are useful because they give satellites a broad view of the Earth, explained Randy Kendall, Vice President for Launch, Missiles and Mobility at the Aerospace Corporation.
"You can access very specific and special types of orbits from Vandenberg, some of the low-Earth orbit, higher inclination, sun-synchronous orbits," said Kendall. "The reason you want to go into one of those orbits is that you want to be in a position to have a very broad view of the Earth."
We also frequently hear the term 'payload' used with rocket launches. It's basically a press-release term that means 'cargo.' Think of the rocket as a delivery vehicle carrying cargo — in most cases, satellite systems — into space.
"When you launch into these higher inclination orbits, you can see all the latitudes up to the poles. That's good from a military perspective. "From a commercial perspective, it's good for a lot of these proliferated low-Earth orbit communications satellites, a lot of NASA Earth observation and climate mapping satellites, things like the Landsat satellite. Specifically, Vandenberg has the perfect location to do a lot of those types of missions that you can't do from the other launch locations."
Kendall has spent 38 years working in the space industry and says the number and variety of launches we are seeing now would have been hard to imagine when he started.
"Yeah, if I rewind the clock back to January of 1988, it was definitely a different time in space. We had just come off of the impacts of the space shuttle Challenger disaster, and NASA was trying to figure out how to get the Space Shuttle flying again.
"The version of me that started at this company never could have imagined the pace and the sheer number of launches and satellites that are going up today. It's truly amazing," he said.
And sometimes, what’s going up there and what’s going on down here can all feel pretty disconnected from ordinary life down here.
"It is hard to make a connection between something that's affecting your daily life and something that is happening tens of thousands of miles away in a space that you can't see and have no conception of," he agreed.
But, says Kendall, take the example of the Global Positioning System satellite, or GPS.
"Maps on your phone, and the only reason that it works is because of GPS. You wouldn't be able to know where you were at all times or where your family members were at all times, or where the Apple tag from your dog's collar is at all the time. Those are all things that work because of this global positioning system," said Kendall.
Whether that's a positive or a negative perhaps depends on whose hands that power is in.
"Yeah, I like to take the optimistic perspective on this," said Kendall. "Clearly, with any technology, there are positive aspects, and there are things that you have to be a little cautious of, but I think by far and away the positive aspects of the things it does for our lives outweigh any cautionary tales."
