THRESHOLD COMPLEX EXPLORATION LOG

Designation / Log ID: 38-I35

Apparent Date/Time: 10 September 2026 / 08:41 (local) — secondary stamp reads 14:09 17 March 1977

Entry Method: Single steel door marked “A-16 INSTRUMENT AIR RECEIVER – AUTHORIZED PERSONNEL ONLY”. Exterior door clear aperture measures 0.94 m × 2.03 m. Interior aperture measures 1.08 m × 1.91 m on entry and 0.81 m × 2.17 m on exit.

Environmental Baseline

Lighting: fluorescent tubes, color temperature measured at 3980 K. Intensity constant at 68 lux.

Ambient temperature: 22.1 °C. Humidity: 38 %.

Background sound: continuous low-frequency compressor residual hum at 47 Hz. Baseline reading 29 dB.

Air movement: none detected. Barometric pressure 1013.4 hPa on entry; 1009.2 hPa after 3.8 m of travel.

Spatial Observations

Gallery estimated 24 m long by 4.8 m wide by 3.2 m high. Laser measurement returns 16.9 m long by 5.9 m wide by 2.6 m high.

Floor: sealed concrete with yellow safety striping. Striping width measures 0.11 m. Surface remains uniform under repeated contact.

Walls: painted steel paneling with embedded receiver vessels. Paint thickness measures 0.8 mm. Surface remains uniform under repeated contact.

Ceiling: exposed structural beams with five recessed lamp fixtures. Fixture count remains five after seven visual inventories.

Repeating motif: every 2.9 m a receiver vessel is mounted at 1.3 m height. Vessel diameter measures 0.72 m. Pressure gauge arrays are identical across all vessels.

Anomalies

Visual inventory of receiver vessels returns 8. Physical inventory returns 8. Measured internal pressure equals 0.0 bar while calculated residual pressure across the same vessels equals 6.4 bar.

Floor remains level under spirit level. Measured dust film on the lower wall panels slopes 1.9° toward the east wall. Slope reverses after 7 minutes of continuous observation without change in physical orientation.

Gallery pressure measures 1013 hPa while the external door indicator reads 1017 hPa. Seal integrity lights remain green.

Sound of residual pressure-relief valve actuation arrives 2.1 seconds after the corresponding surface disturbance is detected. Delay increases by 0.28 s for every additional 1.3 m of distance from the entry door.

Humidity at mid-gallery remains 38 % while condensation forms on the vessel exteriors after 4 minutes of observation. Condensation evaporates without measurable change in local humidity.

Local magnetic field strength measures 0.3 gauss at floor level and 1.9 gauss at 1.4 m height. Field direction reverses after 8 minutes without change in gallery state.

Vessel pressure-gauge needle count on the status array decreases by 2 over 9 minutes while measured pressure at all manifold ports remains 0.0 bar.

Entity Notes

None observed.

At the 6.8 m mark a localized temperature drop of 3.7 °C occurs across a 1.4 m radius. Drop persists for 5 seconds then collapses. No visible source.

Exit / Continuity Status

Exit achieved through the same steel door after 21 minutes of continuous observation. Exterior aperture on exit matches the interior measurement recorded on entry.

Residual effect: left glove retains a thin film of condensation that evaporates over 13 minutes without measurable mass change. Right glove remains dry.

Secondary timestamp on the log device advances 51 minutes while local elapsed time measures 21 minutes.