A NASA satellite has raised its “arm” and unfurled a huge golden antenna — an antenna built in Santa Barbara County — as the craft continues to meet critical milestones in the weeks since arriving in space.
The Soil Moisture Active Passive (SMAP) craft rode to space Jan. 31 aboard a Delta II rocket launched from Vandenberg Air Force Base.
For launch, the large boom and mesh reflector antenna were stowed away into a compact package.
Upon deployment, the truss slowly opened, an act NASA officials likened to a camp chair, before reaching its full diameter of almost 20 feet.
“Deploying large, low-mass structures in space is never easy and is one of the larger engineering challenges NASA missions can confront in development,” said Kent Kellogg, SMAP project manager at the Jet Propulsion Laboratory.
“This week’s result culminates more than six years of challenging reflector and boom assembly development, system engineering and an extensive test campaign.”
Now that the milestone has been accomplished, Kellogg said, the team will turn its attention to the routine science operations that are the main focus of the mission.
The SMAP craft will gather data about the amount of water in the soil across the globe.
On Feb. 24, the team sent commands to deploy SMAP’s reflector antenna at the end of the boom.
Astro Aerospace, a Northrop Grumman Corp. company based in Carpinteria with some operations in Goleta, designed and built the boom and antenna for the Jet Propulsion Laboratory.
The satellite’s unique assembly is an advanced, lightweight rotating deployable mesh reflector antenna system to support the collection of SMAP’s radar and radiometric measurements in space.
It is the first-ever spinning and precision mass-balanced deployable mesh reflector antenna, and is the largest spinning mesh reflector ever deployed in space, NASA officials said.
Astro Aerospace experts have preliminarily determined that the deployed natural frequency of the reflector boom assembly in orbit is nearly identical to prelaunch predictions.
“This provides confidence in the health of the deployed reflector and in its performance once spun up,” NASA officials said.
Despite being 20 feet in diameter, the reflector weighs just 56 pounds. With its supporting boom and launch restraints, the entire reflector and boom assembly weighs only 127 pounds.
“The AstroMesh Reflector is a central feature of the SMAP spacecraft, which will be used to help monitor soil moisture and thus provide critical data about the state of our planet,” said John Alvarez, general manager of Astro Aerospace.
“We are proud to have worked with the NASA JPL team to develop and produce this critical piece of hardware.”
In about a month, after additional tests and maneuvers to adjust the observatory to its final orbit some 426 miles high, ground controllers will begin the process of spinning the antenna to nearly 15 revolutions per minute.
By rotating, the antenna will be able to measure a 620-mile swath of Earth below, allowing SMAP to map the globe every two to three days, NASA officials said.
— 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.