Evryscope

Lore & Background

The first instrument, Evryscope-South, was deployed in May 2015 to Cerro Tololo Inter-American Observatory, where it is co-located with the PROMPT Telescopes. The second instrument, Evryscope-North, was deployed in October 2018 to Mount Laguna Observatory. Evryscope-South is funded by NSF/ATI and NSF/CAREER and was designed and built at the University of North Carolina at Chapel Hill. Evryscope-North is funded in collaboration with San Diego State University.

In March 2016, the Evryscope observed the first superflare that was visible to the naked eye from Proxima Centauri. Proxima increased in brightness by a factor of roughly 68 times during the superflare and released a bolometric energy of 10^33.5 erg, about 10 times larger than any previously detected flare from Proxima Centauri.

The Argus Array Pathfinder, a technological successor with 38 cameras, was deployed in December 2022 at PARI, North Carolina. It serves as a prototype for the Argus Array, which will be a 900 camera survey instrument and replace the CCD technology with MOSFET detectors.

Reader's Guide

The Evryscope's significance lies in its unique design for rapid-cadence, wide-field sky monitoring, enabling the detection of transient events such as the first naked-eye superflare from Proxima Centauri. This detection, observed in March 2016, demonstrated the instrument's ability to capture rare, high-energy stellar phenomena that are orders of magnitude larger than previously recorded flares from that star. The Evryscope's legacy includes serving as a precursor to the Argus Array Pathfinder, a 38-camera prototype deployed in December 2022 at PARI, North Carolina, which itself is a step toward the planned 900-camera Argus Array. The Argus Array will replace CCD technology with MOSFET detectors, indicating an evolution in survey instrumentation. The Evryscope's continuous field of view of 9216 square degrees and its deployment at two observatories (Cerro Tololo and Mount Laguna) underscore its role in all-sky monitoring. Its funding from NSF/ATI and NSF/CAREER, and collaboration with San Diego State University, highlight institutional support for this type of astronomical survey.

Did You Know?

• Each Evryscope contains up to 24 camera units, each with a 6.1 cm telescope.
• The Evryscope's continuous field of view is 9216 square degrees.
• Evryscope detected the first naked-eye superflare from Proxima Centauri in March 2016.
• The Argus Array Pathfinder, a 38-camera successor, was deployed in December 2022.

Modular Architecture and Wide-Field Design Philosophy

The Evryscope instruments represent a distinctive approach to wide-field astronomical surveillance, combining rapid cadence with gigapixel-scale imaging in a compact, modular architecture. Each unit is built around an array of up to twenty-four individual camera modules, and every module pairs a modest 6.1-centimeter (2.4-inch) telescope—specifically an 85 mm Rokinon DSLR lens—with a thermoelectrically cooled astronomical CCD sensor. Rather than relying on a single large aperture, the design distributes many small, identical optical channels around a rigid solid-fiberglass structural frame. This arrangement yields a single, uninterrupted field of view spanning 9,216 square degrees, an enormous swath of sky captured simultaneously. The use of off-the-shelf consumer optics married to precision cooled detectors gives the system a cost-effective, scalable character, while the fiberglass backbone keeps the relative geometry of the cameras stable. The result is an instrument family engineered not for deep-space resolution but for sweeping, frequent snapshots of the entire visible sky, making it uniquely suited to catching transient and unpredictable events.

Twin Hemispheric Deployments and Institutional Partnerships

The two Evryscope instruments found homes on opposite sides of the globe, each tied to a different institutional partnership. Evryscope-South was installed in May 2015 at the Cerro Tololo Inter-American Observatory in Chile, where it shares its site with the PROMPT Telescopes. Its development was supported by two National Science Foundation grants—one under the ATI program and another under the CAREER program—and the instrument was both designed and assembled at the University of North Carolina at Chapel Hill. Nearly three and a half years later, in October 2018, Evryscope-North went into operation at Mount Laguna Observatory in California. This second unit was developed in collaboration with San Diego State University, broadening the geographic and institutional footprint of the survey. By placing one instrument in the Southern Hemisphere and the other in the Northern, the program gains complementary sky coverage throughout the year. The co-location at Cerro Tololo alongside PROMPT also creates a natural synergy, allowing the two systems to cross-check and complement one another's observations of transient sky events.

The Naked-Eye Superflare from Proxima Centauri

In March 2016, Evryscope recorded what would become a landmark detection in stellar astrophysics: the first superflare from Proxima Centauri bright enough to be visible to the unaided human eye. During the event, the red dwarf's luminosity surged by a factor of approximately sixty-eight, and the total bolometric energy released reached 10 to the 33.5 ergs. To put that in context, the flare was roughly ten times more energetic than any flare previously recorded from Proxima Centauri, making it an extraordinary outlier even for a star already known for violent magnetic activity. The detection was made possible by the instrument's rapid, repeated imaging of the full sky; a transient of this kind, lasting only minutes, would be easily missed by slower survey cadences. The event earned the informal title 'The First Naked-Eye Superflare Detected from Proxima Centauri' and immediately drew attention to how common such extreme flares are among the red-dwarf stars that dominate our galaxy. For the Evryscope team, it validated the core premise that wide-field, high-cadence monitoring can uncover physics that targeted observations simply never anticipate.

From Evryscope to the Argus Array: A Scaling Roadmap

The Evryscope program has served as a proving ground for the next generation of wide-field transient surveys. In December 2022, the Argus Array Pathfinder—a technological successor equipped with thirty-eight cameras—was deployed at the PARI facility in North Carolina. This instrument is explicitly designed as a prototype for the full Argus Array, a far larger survey system planned to incorporate nine hundred cameras. A key technical leap in that future instrument is the replacement of the CCD sensors used in the Evryscopes with MOSFET-based detectors, a shift that promises improved speed, lower noise, and greater dynamic range for the kind of rapid, repeated sky snapshots the Evryscope pioneered. The progression from twenty-four cameras to thirty-eight to nine hundred illustrates a clear scaling strategy: validate the concept with a modest array, refine the engineering in a mid-size pathfinder, and then deploy at survey scale. The Evryscope's role in this lineage is that of the foundational proof-of-concept, demonstrating that a compact, multi-camera, rapid-cadence architecture can deliver scientifically transformative detections while remaining within the budget and engineering reach of a university-led team.