HomeScienceLCS-1 – The Oldest Functioning Satellite
LCS-1 – The Oldest Functioning Satellite
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LCS-1 – The Oldest Functioning Satellite
A large, hollow, aluminum sphere with a precisely defined cross-section has been orbiting the Earth since 1965 and is known as the Lincoln Calibration Sphere 1. Even though it has no power and no electronics, it is considered the oldest functioning satellite. It was launched along with the Lincoln Experimental Satellite-2 on a Titan IIIA.
This is because the metal sphere still functions as it was intended, which was to calibrate ground-based radars. Calibration of radar requires the use of known data against which the output of the radar can be compared. It has been used to calibrate radars since the launch of LCS-1. Rohr Corp built it for MIT Lincoln Laboratory.
A radar may be fine-tuned in this way to ensure that its output is consistent with what is expected. They are an effective tool for calibrating radars because they have a consistent Radar Cross Section (RCS). In any case, if more accurate tracking tools are available for satellite tracking, such as lasers, radar position data could also be calibrated by the same satellites.
In 1965, Lincoln Calibration Sphere 1 was launched. In attempts to launch two more calibration spheres, designated LCS 2 and LCS 3, launch failures occurred. A successful launch of LCS 4 took place in 1971, and the spacecraft is expected to last about 75 years. With a predicted lifespan of 30,000 years, LCS 1 is likely to outlive humanity.
There are also active calibration satellites equipped with transponders that emit a signal on command, in addition to passive satellites like the Lincoln Calibration Spheres. Ground radar stations send transmission commands and measure the satellite’s location using the results. Using the satellite’s ephemeris data and the transponder’s signal, a radar receiver computes the satellite’s precise position.
In order to determine whether the radar measurement is accurate, this position is compared to the location obtained from the radar measurement. In the 1960s, Surveillance Calibration (or SURCAL) was launched, as was RADCAL (short for RADar CAlibration Satellite) from 1993 to 2013.
