LES 2

About This Satellite

LES-2 was an active X-band communications experiment developed by MIT Lincoln Laboratory. Unlike a passive reflector, it amplified received signals before retransmission. It followed LES-1 with revised separation circuitry and successfully reached the intended elliptical orbit in May 1965.

A higher apogee made the communications test more useful

The intended apogee was about 15,000 km. LES-1 had remained near 2,800 km after its propulsion-system failure, limiting concurrent visibility from widely separated terminals. LES-2's successful orbit allowed the longer shared viewing opportunities needed for more representative communications experiments.

Electronic antenna selection compensated for a spinning body

The twin spacecraft used Earth-sensor measurements to select among eight horn antennas. Switching the connected antenna helped direct the radio link while the spacecraft rotated. It did not turn the entire satellite into a continuously Earth-pointing, three-axis-stabilized platform.

Mission reference: MIT Lincoln Laboratory: LES-2 orbital recovery lessons and X-band experiments. Editorial review: 2026-09-14.

The terminal contributed coding, sensitivity and speech processing

Lincoln Laboratory's history describes companion LET ground equipment with speech compression and reconstruction, convolutional coding, and sequential decoding. LET-1 also used a cooled receiving amplifier to improve sensitivity. These were features of the end-to-end experimental system, not all electronics carried aboard LES-2. Assessing the link solely from satellite transmitter power would omit the capabilities of the receiving antenna and processing equipment.

Reference: MIT Lincoln Laboratory history, Satellite Communications: LET ground-terminal technology.

The famous later radio detection belonged to LES-1

MIT records transmitter shutdown for both early LES spacecraft in 1967, but attributes the unexpected 2012 telemetry detection specifically to LES-1. Similar construction does not transfer that observation to LES-2. This profile retains LES-2 as a historical experiment and does not advertise a revived communications service.

Reference: MIT Lincoln Laboratory: 1967 shutdown and the separate LES-1 telemetry rediscovery.

Reading this orbital snapshot

Based on TLE epoch: 2026-09-02. Estimated altitude ranges from 2,773 km at perigee to 14,803 km at apogee, a difference of 12,031 km. The orbital period is about 309.8 minutes. Eccentricity 0.39663 shows why a single altitude cannot describe the whole path. In a two-body approximation, perigee speed is 2.31 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 32.20 degrees implies approximate geocentric ground-track limits of 32.2 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 1360 · GCAT: S01360 (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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