Remote Sensing in the Desert

THE CENTER'S DESERT RESEARCH STATION (DRS), in a remote valley west of Barstow, was the site of the second half of the two-part Remote Sensing: Explorations Into the Art of Detection exhibit. While the Los Angeles exhibit examined places and history in the urban and suburb realm, programs at the DRS explored phenomenology and remote sensing in the field.

The DRS is under the airspace of Edwards Air Force Base, in a busy testing and aerospace tech region of the Mojave Desert that includes China Lake Naval Air/Ground Center, Mojave Air and Space Port, JPL’s Goldstone antenna complex, Air Force Plant 42, and other commercial aerospace test ranges and droneports. The skies above the Desert Research Station quake with sonic booms, and buzz with electromagnetic resonances, much of which falls within the conceptual realm of remote sensing.

Remote sensing employs multispectral scanners sensing the waves of energy that run between all things, across the electromagnetic spectrum. These waves are everywhere and all around us. Low frequencies move passively though outer space and through the earth itself, while high frequencies excite molecules, making heat and radiation.

Much of the lower end of the spectrum, with its longer waves, is radio, which can be used in communication, generated by transmitters, and detected by receivers. Above radio waves are microwaves, which are also used in communications and electronics. In the middle of the spectrum is visible light, which our eyes have evolved to detect, bounded by ultraviolet and infrared, out of sight, but heavily used for imaging by remote sensing satellites. At the upper ranges of the electromagnetic spectrum, energy waves shrink to molecular and atomic sizes, and technologies use x-ray machines and particle accelerators to generate and detect the waves.
 

Research projects at the DRS have been exploring things like remote sensing phenomenology for more than 20 years. Participation in the Getty Foundation's PST ART: Art & Science Collide initiative provided support for several new programs, which were featured in displays inside the visitor center, and outside on the grounds.

Some of these projects explored the relationship between detection and observation. Others sought ways to make the invisible infrastructures of the electromagnetic spectrum apparent, and to describe their shape and extent. And others explored the fragile fringes of perception, where nuances are vulnerable to misidentification—by accident, or intent—and remain alive to reinterpretation.

The focus of the projects ranged from the earth to the solar system. From low to high, they probed the space between the immediate, material ground outside, and the sky above it; to the fluid and dynamic realm where the atmosphere transitions to space; then to space itself, where satellites stare fixedly back down at the earth, reverberating with remotely sensed data, or gaze outwards, back towards the beginning of time.

Each of the projects had some kind of physical manifestation outside, on the grounds of the DRS, visible from a walking trail.
 

Radome
Dominating the grounds visibly was a white radome, more than 20 feet in diameter; a structure that was both functional and symbolic. Radomes house the hardware for radar and telemetry, the connection points of remote sensing and communication, protecting them from the elements, and from view—revealing presence, while concealing methods.
 
Radomes have roots in the idealistic architecture of R. Buckminster Fuller, whose hemispheric geodesic dome designs of the 1960s and 1970s inspired many to imagine alternatives for architecture, culture, and society. At the same time, hundreds of his geodesic radomes were installed across the nation and the globe, as practical protective covers for radar antennas used for defense purposes. Radomes extend beyond the classic 180-degree geodesic dome, into triquadraspheroids of 270 degrees, or more, approaching the Euclidian totality of a geodesic sphere, closer to the form of the earth itself.

The radome at the DRS provided space for temporary research projects, as well as a space for groups to meet, projecting ideas and images inside a structure that is all about connecting to an outside that reaches across terrain, and into the universe above.
 

Anechoic Theater
Like an inversion of the outward-looking radome, anechoic chambers are spaces where the outside world is eliminated, as much as possible. They are often used to develop and test electromagnetic technologies for aerospace, including electronic warfare measures and countermeasures. The largest anechoic chamber in the world is located nearby, at Edwards Air Force Base, where entire aircraft can be tested inside.

The chamber at the DRS, in its isolation basin, did not have the electromagnetic wave-cancelling pylons of an actual anechoic chamber. Instead it provided a zone for exploring the phenomenology of these spaces through video and sound. Similar to anechoic chambers, theaters shut out their physical contexts in order to focus attention on a rectangular screen and controlled sound.

Tests performed inside the Anechoic Theater included dissonatic transplacements, involving the reassembling of video/audio programs related to anechoic chambers and stealth technology.
 

Aelectrosonic Truss
A large induction loop antenna was constructed on the grounds of the DRS to manifest some of the very low frequency (VLF) portions of the electromagnetic spectrum. The truss pivots on its vertical axis to adjust reception of the invisible waves emanating continuously from human and non-human sources.

This unique antenna was designed and built by Deborah Stratman and Steve Badgett, principal investigators of the project. More than nine miles of copper wire, coiled around a steerable framework, collect energy, which is then emitted through a speaker. It is likely the largest of its type ever constructed. The emanations it captured include distant lightning strikes, submarine communications, solar activity in the ionosphere, and long-distance electrical transmission infrastructure.

Radio Tower
A number of radio frequency antennas were elevated above the ground at the DRS by a standard triangular guyed tower, to detect a range of frequencies along the ultra high frequency (UHF) and very high frequency (VHF) portions of the electromagnetic spectrum. These frequencies are common carriers for voice and device communications, originating from other towers on the ground, as well as from moving vehicles and aircraft.

Inside the main building of the DRS, a control room collected and processed signals from these antennas, along with signals recorded using similar antennas around the region by Rob Ray, the principal investigator of this ground-based radio remote sensing project.

The air above and around the DRS is in the restricted airspace known as the R-2508 Complex, one of the nation’s busiest aerospace testing and training airspaces, which extends to the Owens Valley, and to the Nevada state line, covering China Lake Naval Weapons Station and Fort Irwin. 

The airspace is managed by Edwards Air Force Base, out of a communications center on base called Joshua Control. R-2508 is full of unusual RF transmissions that can be monitored from the ground. Though many are digitally scrambled and indecipherable, some voice communications and other sonic patterns can be interpreted, giving a sense of otherwise invisible and unknown activities occurring in this unique space.

Tree Antenna
A Joshua tree at the DRS has been designated as an antenna and data node by the Space Song Foundation, as part of a long-term project that examines trees as individual communicative entities, and trees collectively as a sensory layer on the planetary surface.

Electronics on trees in the Space Song network collect information about light, moisture, and temperature, creating a unique identity for each tree in the system, while also acting as living antennas that receive transmissions from space. At the DRS, the Joshua tree’s live data was mixed with intermittent pings from orbiting spacecraft to create a sonic expression heard through a speaker on the tree.  

Space Song explores how trees operate like organic antennas, with branches reaching out to collect waves from space, and roots that provide structural support, energy grounding, and rhizomic networking potential.

Starlink Link
Two adjacent antennas on the roof of a DRS building interact with Starlink satellites. One antenna serves the station as the internet service provider; the other monitors the satellites providing this service. 

Julia Christensen, the principal investigator of this remote sensing project, used this binary node to explore the behavior of this system, and the relationship between low earth orbit and the ground, upload and download.

The added antenna, called a low frequency noise blocker, converts the beacon signals sent back and forth between the Starlink antenna and passing satellites, at about 12.5GHz, into frequencies that are then processed, logged, and made visible by software. Traveling west to east through space, the same direction as the earth’s rotation, the satellites move quickly past the coordinates of the receiver’s signal, and hand off the connection to the next closest satellite. Some of the highlights of many months of monitoring and recording were presented on screens in the exhibit hall of the DRS.

Starlink satellites orbit in a layer that is around 340 miles above the earth. Each one weighs close to a ton, and travels at 17,500 miles per hour. First launched in 2019, there are now more than 7,000 Starlink satellites in service, more than all the other satellites in existence, combined, and thousands more are planned. They communicate with one another in space, like a global network in the sky, using RF and lasers. This network is linked to an earthbound network, through lasers pointed at gateways: terrestrial antennas housed in thousands of small radomes all over the globe, connected by fiber optic cables.

Starlink is just the first of several companies developing systems using hundreds or thousands of satellites to provide internet connectivity to the globe. Among the others is Amazon, which just launched the first batch of its planned constellation of 3,200 satellites. Soon data centers will be up there too, taking advantage of solar energy, cold temperatures, and burgeoning bandwidth. Low earth orbit is the wild west of the information age. ♦