Sonic-boom UFO show! SpaceX launches satellite, lands rocket booster in California

Los Angeles Mayor Eric Garcetti tweeted out this picture of the SpaceX Falcon 9 rocket’s contrail, glowing in Southern California’s skies after sunset. “Nope, definitely not aliens,” Garcetti wrote. (@MayorOfLA via Twitter)

SpaceX’s Falcon 9 rocket executed its first on-land touchdown on the West Coast tonight after sending Argentina’s SAOCOM 1A satellite into orbit, putting on a show punctuated by a sonic boom for Southern California.

After a trouble-free countdown, the two-stage rocket blasted off right on time at 7:21 p.m. PT from California’s Vandenberg Air Force Base, leaving a post-sunset contrail glowing in the cloudless skies above.

Minutes after launch, the rocket’s second stage separated from the first-stage booster and continued rising spaceward. The booster, meanwhile, relit its engines to maneuver itself for the return trip to SpaceX’s landing zone, not far from the launch pad. The retro firings slowed the rocket down from supersonic speeds, setting off a sonic boom that could be heard in some areas (but not others).

Cheers went up from SpaceX’s headquarters in Hawthorne, Calif., as webcams showed the first stage setting itself down on Landing Zone 4. (The other landing zones are in Florida for East Coast launches.)

“Vandenberg, LZ-4, the Falcon has landed,” a member of SpaceX’s launch team reported.

Later, SpaceX reported that the SAOCOM 1A radar satellite was placed in its proper pole-to-pole orbit. “This is fantastic news,” SpaceX launch commentator Tom Praderio said.

The satellite will be operated by Argentina’s space agency, known as the National Commission on Space Activites or by its Spanish-language acronym, CONAE.

The SAOCOM 1 mission aims to study soil moisture using synthetic-aperture radar readings from two identical satellites in low Earth orbit, SAOCOM 1A and 1B.

SAOCOM 1, together with the Italian COSMO-SkyMed X-Band SAR constellation, make up the Italian-Argentine Satellite System for Emergency Management, or SIASGE. Flying both satellite constellations along the same orbit supports a rapid response by providing radar readings in emergency situations.

Proving out a successful booster retrieval system at the former site of Vandenberg’s Space Launch Complex 4W marks another step in SpaceX’s drive to increase rocket reusability and as a result drive down the cost of access to space. SpaceX had previously landed five Falcon boosters at sea after West Coast launches, but this was the first West Coast attempt to pull off a “land landing.”

There have been 30 successful SpaceX booster landings in all, including the at-sea and on-land touchdowns in Florida.

SpaceX has also been experimenting with a procedure to save additional millions of dollars by retrieving the Falcon 9’s fairing, or nose cone. During previous West Coast launches, it sent out a ship equipped with a giant net to catch parafoil-equipped components of the nose cone as the descend. This time, however, the ship — nicknamed Mr. Steven — stayed in port, perhaps due to rough seas in the Pacific.

The fact that the launch and landing took place near Los Angeles meant there were ample opportunities for Southern Californians to catch the show (and for unwitting observers to register UFO reports). Here are some of the reactions and images tweeted out afterward:

Amazing! Incredible! pic.twitter.com/srNUadi0i4

— Mehmet (@mhmtkcn) October 8, 2018

Crowds at @Disneyland watched @SpaceX launch. One kid was quoted as saying: “Is this the end of the world?” #spacex (CC: @b0yle @geekwire) pic.twitter.com/e8frQkGCU2

— Brian M. Westbrook (@BrianWestbrook) October 8, 2018

My mom just texted me these pictures she took from their front yard. Wow. #SpaceX pic.twitter.com/BP9waQv8Ug

— Shannon Stirone (@shannonmstirone) October 8, 2018

Did any of you look unto the sky!? What the heck is that?? #UFO pic.twitter.com/Lyur3ovIXw

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