Keo Sentry


Keo Scientific designs and manufactures highly sensitive all-sky and narrow-field multi-spectral (wavelength-resolved) imagers for low-light-level auroral and airglow studies. Several options are available: color, panchromatic, single-filter and filter-wheel based instruments, with fields of views ranging from 1 to 180 degrees. VIS, NIR and IR optimized imaging at speeds as fast as f/0.7, onto a wide selection of different CCDs, sCMOS, and Electron Multiplying CCDs (EMCCDs). Recent innovations include f/0.95 fisheye optics for commercial full-frame DSLR cameras. Our custom imagers are also used for meteor physics, studies of upper-atmospheric lightning (sprites/jets/elves), noctilucent clouds and infrared (IR) aurorae.

▶ More information here.



Keo Scientific designs and manufactures a wide range of highly sensitive photometers built around low-noise deep-cooled photomultiplier tubes (PMTs) as well as other more recent photon-counting sensor technologies. Leveraging almost 40 years of actual field experience, we go beyond textbook optics' knowledge and design photometers ideally suited to deal with the many non-obvious issues and problems associated with measuring the aurora borealis and australis. Single-filter, filter-wheel based, and multi-filter beam-split options are available for staring-mode as well as meridian-scanning operations.

▶ Additional details here.

Fabry Pérot Interferometer (FPI)


Keo Scientific designs and manufactures a range of Fabry-Pérot Interferometers (FPIs). Both all-sky and scanning Fabry-Pérot interferometers are available for observations of winds and two-dimensional atmospheric parameters in the thermosphere/ionosphere and the mesosphere region by the measurement of Doppler shift and broadening of emission lines originating from within those regions.

▶ More information here.



Keo Scientific Ltd. has proudly teamed up with what is arguably the world-leading expert on spectrograph design for airglow and aurora research, Jeffrey Baumgardner of Boston University. We are thus in a position to design and build the highest-quality spectrographs, whether grating- and grism-based, uniquely suited to your particular atmospheric and ionospheric research needs. For more information, please contact us with your particular sensitivity, spectral coverage and resolution requirements.

We have recently designed an innovative, compact grism-based patrol spectrograph, providing continuous coverage of the 390–740 nm wavelength range (other ranges available) simultaneously across the entire 180 degree meridian (in effect a solid-state meridian scanning photometer), in a very compact package. Optionally single-photon sensitivity, and Quantum Efficiency of approximately 90% across the range covered range. There is also a "Convertible" option to turn the spectrograph into a 2-inch all-sky imager via remote control. Optional filter wheel (neutral density), shutter, and interchangeable Field of View Modules available. This spectrograph is targeted at space weather, aurora, and light pollution research.

Keo SkyScan


Keo Scientific designs and manufactures articulated first-surface mirror assemblies with a variety of aperture sizes. Use with narrow field imagers, photometers and Fabry-Pérot Interferometers (FPIs), or as a Heliostat.

▶ For additional details go to our Keo SkyScan page.

Low Brightness Sources


Keo Scientific designs and builds portable LOW BRIGHTNESS LIGHT-SOURCES (LBS) suitable for use in auroral research. Manual and remote-controlled units are available (calibrated, as well as uncalibrated).

▶ More details here.

Keo BK-7 Glass Dome


Our custom 9.25” diameter hemispheric observing dome is made of BK-7 grade mineral glass which is finely ground and coated to the highest standard of precision. The geometry and size of this dome is meant to accommodate the ultra-wide field of view fisheye lenses of all Keo Scientific allsky imagers, without obscuring parts of the field of view. The dome will also accommodate optional accessories, such as the Keo SunShield (below).

▶ See this brochure for additional details on this high-transmission observing dome.



The Keo SunShield is a clamshell-type front shutter which serves to protect the primary lens of your Keo imager from exposure to solar radiation during daytime. The clamshell fully retracts when open, leaving the all-sky (fish-eye) field of view unobscured.

▶ See this brochure for additional details.



A riometer (relative ionospheric opacity meter) is an instrument used to quantify the amount of electromagnetic wave ionospheric absorption in the atmosphere. As the name implies, a riometer measures the "opacity" of the ionosphere to radio noise emanating from distant stars and galaxies. In the absence of any ionospheric absorption, this radio noise, averaged over a sufficiently long period of time, forms a quiet-day curve. Increased ionization in the ionosphere will cause absorption of radio signals (both terrestrial and extraterrestrial), and a departure from the quiet-day curve. The difference between the quiet-day curve and the riometer signal is an indicator of the amount of absorption, and is measured in decibels. The Riometer was developed in the mid 1950s by scientists at the University of Alaska who were researching the radio propagation effects of aurora. Five years in the making, Keo Scientific's new riometer may be considered a 'next-generation' riometer.

▶ See this page, or email us for additional details.



We provide full absolute spectral calibration and imager/photometer characterization services using our NIST traceable in-house integrating sphere, custom-built and calibrated especially for the extremely low light-levels encountered in atmospheric and ionospheric research.

▶ More information in this informational brochure.

Keo Synopticx Software


KeoSynopticx provides an easy to use imager control interface for automated imaging operations. It enables the synchronization of filter selection, CCD/exposure settings and shutter operation through a Graphical User Interface.

▶ Download the User's Manual here.