The re-entry of a used Chinese rocket body seen in the sky as a fireball Wednesday night wasn’t a surprise to crews at Vandenberg Air Force Base, who routinely track space debris.
Thousands of people on the Central Coast and western United States reported seeing the fireball streak across the sky after 9:30 p.m.
Military officials say the object was a used rocket component from a June 25 launch in China.
It’s among more than 16,000 objects tracked and cataloged daily by crews in the Joint Space Operations Center at Vandenberg, Capt. Nicholas Mercurio, JSpOC spokesman, said.
The system tracks objects 4 inches or larger, typically something as small as a softball, Mercurio said.
The spent rocket body, estimated at 30 feet long, re-entered the atmosphere over California at 9:36 p.m., Mercurio said.
Crews can predict the time of re-entry and the relative location over Earth where re-entry will occur.
“After that there are so many forces acting upon the object that we cannot predict where, if anything survives re-entry, it may land,” Mercurio said.
Tracking of space objects, including operational satellites and debris like that seen Wednesday night, is performed through Space Surveillance Network, a global collection of radar and electro-optical sensors automatically tasked to take more than 400,000 observations each day, Mercurio said.
Those observations are put into computer system software that lists orbital positions of manmade objects in space.
While Wednesday night’s display was especially vibrant, re-entry of space objects occurs regularly.
In 2015, JSpOC crews reported that 110 objects re-entered the atmosphere.
“But obviously very few, if any of them, were visible to the naked eye because they were either so small they burned up in the atmosphere or it happened during the daytime where you could not see it,” Mercurio said. “Last night what we had was a larger object during the evening time when most people were awake and able to see it.”
The American Meteor Society had 60 observations logged on its website most by people in California, Nevada and Utah.
Reports about the fireball immediately spread on social media on Wednesday night, creating a busy Thursday for Mercurio.
“I’ve been on the phone all morning,” he said.
Free notifications about objects re-entering the atmosphere are provided at space-track.org.
“It’s part of our commitment to maintaining space flight safety for all,” he said.
For decades, Air Force crews in Colorado conducted the space tracking mission which was relocated to Vandenberg more than seven years ago.
Earlier this month, those involved in the space catalog job at Vandenberg became part of the new 18th Space Control Squadron, which will fall under the 21st Space Wing at Peterson AFB, Colorado.
— Noozhawk North County editor Janene Scully can be reached at jscully@noozhawk.com. Follow Noozhawk on Twitter: @noozhawk, @NoozhawkNews and @NoozhawkBiz. Connect with Noozhawk on Facebook.