TIROS 8

About This Satellite

TIROS 8 launched on December 21, 1963 and introduced Automatic Picture Transmission, or APT, to the TIROS programme. Properly equipped local stations could receive its weather pictures directly. The innovation concerned how observations reached users as well as how they were made: a useful satellite image no longer had to follow only a central receiving route.

Two camera systems had different useful lifetimes

NOAA records degradation of the APT camera ending that experiment in April 1964. A separate wide-angle television camera continued providing useful pictures until February 12, 1966, while final deactivation came on July 1, 1967. These dates should not be compressed into a claim that APT was transmitting throughout the entire mission.

A historic direct broadcast is not a signal to receive today

The record explains an early distribution experiment, not an available radio service. Seeing a TIROS 8 orbital track today does not establish that any original transmitter is active. Likewise, the period of a preserved image collection can differ from both the APT experiment and the spacecraft's final shutdown.

Mission reference: NOAA NESDIS: TIROS-8 launch and direct-readout experiment. Editorial review: 2026-09-12.

Exposure time and transmission time were very different

NASA's experiment catalog describes an eight-second exposure followed by roughly 200 seconds of picture transmission. An 800-line image was sent at four lines per second. The receiver assembled a picture over time; it was not watching a modern continuous video stream. This timing helps explain the practical constraints of the early direct-readout system.

Reference: NASA experiment catalog: TIROS-8 APT image timing.

The receiving station was part of the innovation

NASA's later APT retrospective describes the importance of relatively inexpensive receiving equipment and the evolution of the ground systems. Direct access reduced dependence on a central image delivery chain, but still required suitable equipment and processing. Direct broadcast describes the distribution architecture; it does not mean that an ordinary radio could automatically display a weather picture.

Reference: NASA Spinoff: Automatic Picture Transmission ground systems.

Reading this orbital snapshot

Based on TLE epoch: 2026-09-05. Estimated altitude ranges from 634 km at perigee to 667 km at apogee, a difference of 33 km. The orbital period is about 97.7 minutes. Eccentricity 0.00235 indicates a nearly circular path. In a two-body approximation, perigee speed is 1.00 times apogee speed. These are mean-element estimates, not instantaneous measurements. Distance per orbit uses an ellipse approximation.

Saved build snapshot. If a valid TLE is retrieved, this explanation and the orbit panel update together. Otherwise this dated snapshot is retained.

Ground track is not sensor coverage

An inclination of 58.49 degrees implies approximate geocentric ground-track limits of 58.5 degrees north and south. This is a prograde orbit, moving in the same general direction as Earth rotation. The plotted line marks the point beneath the object. It does not represent camera coverage, radio reception, or a guaranteed visible pass.

Accuracy and missing information

The introductory record describes the build snapshot. The orbital snapshot explanation and orbit panel share any successfully retrieved TLE; check the displayed epoch. Reentered objects retain historical data only. Mission history is not rewritten by TLE updates. TLE/SGP4 positions are predictions and can change after maneuvers or updated observations. The 14-day stale-data cutoff is a display safeguard, not an accuracy guarantee. Local passes are geometric predictions, not a visibility forecast. No verified operator or mission status means unknown, not active. Do not use this catalog for collision avoidance or operational flight decisions.

Catalog sources: CelesTrak SATCAT: NORAD 716 · GCAT: S00716 (source update 2026 Sep 4 2345:57). Supplementary metadata: SatNOGS DB, retrieved 2026-09-05T12:57:25.375Z. Page assembled 2026-09-15. GCAT phase codes describe trajectory phases, not mission health.

Learn more: TLE data · Perigee and apogee · Ground tracks · JOT (Jewawud Live Orbital Map)

Satellite Details