TIROS 1

About This Satellite

TIROS 1 launched on April 1, 1960 to test whether television pictures from orbit could support weather observation. Its two cameras and onboard recorders helped establish a practical link between an experimental spacecraft and meteorologists on the ground. The mission lasted 78 days, not the decades suggested by the continued presence of its catalog entry.

The cameras did not always face Earth

The spacecraft was spin-stabilized and maintained an orientation in space rather than continuously pointing toward Earth. Cameras were operated when they faced a sunlit part of the planet. A pass over a location was therefore not, by itself, a guarantee that TIROS 1 photographed it.

Recording made observations possible between contacts

Each camera had a magnetic tape recorder so images could be stored outside ground-station range. Taking an image and delivering it were different events. This is an early example of why a ground contact schedule should not be read as the complete observation schedule of a spacecraft.

Mission reference: NASA: TIROS-1 payload and observing constraints. Editorial review: 2026-09-12.

A short mission could still prove the concept

NOAA reports 19,389 usable pictures and identifies TIROS 1 as the first successful weather satellite. Its contribution was demonstrating useful cloud observations, not inventing the first image ever taken from space. That qualification also distinguishes it from earlier, less successful meteorological experiments such as Vanguard 2.

Reference: NOAA NESDIS: TIROS-1 usable images and historical milestone.

Images became a ground-based weather product

The received images were recorded onto 35 mm film to produce prints. Forecasters then had to interpret the cloud patterns. The satellite provided observations, not a complete forecast by itself; a modern-looking map of its orbit cannot reproduce that historical processing chain or supply new TIROS 1 weather imagery.

Reference: NOAA NESDIS: receiving and processing TIROS images.

Reading this orbital snapshot

Based on TLE epoch: 2026-09-05. Estimated altitude ranges from 617 km at perigee to 649 km at apogee, a difference of 32 km. The orbital period is about 97.4 minutes. Eccentricity 0.00227 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 48.38 degrees implies approximate geocentric ground-track limits of 48.4 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 29 · GCAT: S00029 (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)

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