Clesthyra's Eye

First Appearance and Context

During a visit to the rooftop Starhenge (stone observatory) above the Praesidium (rooftop precinct) in the Mynster (temple–clock complex), avout (cloistered scholars) identify a small, fixed fisheye instrument pointed at the zenith. Named for the mythic watcher Clesthyra, it is set into a stone pedestal with a slot sized for a Photomnemonic Tablet (light‑recording tablet).

Roles/Actions and Affiliations

• All‑sky recorder: Captures the entire sky in a single view, well‑suited to registering transient streaks from fast‑moving objects.
• Daylight capture: On clear days its all‑sky recordings also include the Sun’s position; these sequences can be reviewed on a photomnemonic tablet.
• Recording cadence: With a tablet inserted, it accumulates observations continuously until the medium is full; at typical settings, a single run can span months.
• Complement to telescopes: Provides continuous coverage while dome‑housed instruments target specific fields.
• Tablet handling: The Eye’s protected slot has been used to place a photomnemonic tablet for later retrieval; during a formal aut (ritual service) at the Mynster, an avout accessed the starhenge and withdrew a tablet that had been left there earlier. Observers later inferred that when a tablet from another rooftop instrument (the Mithra/Mylax assembly) was collected at the direction of Fraa Spelikon, the tablet in the Eye was not removed and its long‑run recording continued.
• Polar‑orbit analysis example: Time‑integrated stills produced on the tablet from all‑sky data reveal concentric star trails and repeated, nearly straight north–south streaks near the pole star, enabling identification of multiple polar‑orbiting satellites in a single night’s record.
• Reference for navigation optics: A sextant employing a wide‑angle lens like Clesthyra’s Eye can recognize constellations; combined with the apparent positions of the sun, the moon, and Arbre and an internal clock and ephemeris, it can be used to calculate orbital elements for attitude and trajectory work.
• Public signaling: In later discussion, an avout remarks that Sammann “showed himself in Clesthyra’s Eye,” using the Eye’s conspicuous visibility to signal that he possessed information without explicit disclosure.
• Incidental self‑image: One avout later recalls inadvertently seeing his own sobbing face captured by the Eye after an aut of Anathem (expulsion rite), illustrating that the instrument can also register nearby figures under its lens.

Relationships

• Part of the rooftop complex and physically mounted on the Praesidium above the Mynster; designed to work with a photomnemonic tablet.
• Regularly maintained by the Ita (technical order), who clean the optics and inspect the access covers.

Descriptions/Characteristics

• Form: A small dome‑like fisheye lens aimed at the zenith, fixed in place with no moving parts.
• Adjacent reference: A zenith mirror stands next to the Eye on its pedestal; in all‑sky recordings the mirror’s support creates a distinctive notch that can be used for orientation.
• Protection: A dust cover shields the lens and tablet slot; it must be opened to insert or remove a tablet.
• Imaging behavior: Under all‑sky projection, fixed stars form circular trails due to the world’s rotation, while fast‑moving objects trace straight, faint tracks. The Eye does not track the sky.
• Observed upkeep: An Ita technician—identified as Sammann—has been seen polishing the lens and mirror and briefly checking the tablet slot cover; on one occasion he retrieved a loose paper dust jacket from the installation. In a later visit he placed a dust‑jacketed bundle on the parapet in plain view while eating, and on another clear day wore very dark, arc‑type goggles and spent his lunch looking toward the Sun.

Current Status/Location

Installed and in use on the rooftop, active during permitted work and observations; access follows the roof’s availability under the Discipline. Regular cleaning visits by the Ita have been observed; the instrument remains in place.