Sixty years ago today the Vanguard satellite was launched on March 17, 1958, It is the oldest man made satellite to still be in orbit and it should stay in orbit for about another 200 years. It was not the first satellite to make it into space, that distinction of course goes to the Russian’s Sputnik, or even the first American satellite. It was in fact the fourth satellite, but it was the first one to utilize solar cells and the first to verify that the Earth is not perfectly round but a bit pear shaped through orbit analysis..
It is really a very tiny craft and was nicknamed the grapefruit.
From Wikipedia:
The spacecraft is a1.47 kg (3.2 lb) aluminum sphere 16.5 cm (6.4 inches) in diameter. It contains a 10 mW, 108 MHz transmitter powered by a mercury battery and a 5 mW, 108.03 MHz[5] transmitter that was powered by six solar cells mounted on the body of the satellite. Six short antennas protrude from the sphere. The transmitters were used primarily for engineering and tracking data, but were also used to determine the total electron content between the satellite and the ground stations.Vanguard also carries two thermistors which measured the interior temperature over sixteen days in order to record the effectiveness of the thermal protection.
To launch this three pound grapefruit, the U.S. used a three stage 72 foot tall, 22,000 pound Vanguard rocket. No doubt everyone involved were a bit nervous before the launch, because the previous launch did not go quite so well...
But on March 17,1958 everything went perfect TV-4.
Vanguard 1 successfully achieved an orbit of:
Perigee: 656.6 km
Apogee: 3,841.2 km
Inclination: 34.3°
Period: 132.7 minutes
Which looks like this (Heavens Above).
It immediately started transmitting back to Earth.
Here is what it sounded like.
The engineers were not convinced the solar cells would work and include a mercury battery. But after the battery ran out, Vanguard 1 continued to transmit, and did so for another six years. In fact it seems to wake up from time to time and resume transmitting Vanguard 1’s signal was reported to be picked up as recently as 2017.
Over the last 60 years, Vanguard 1 has gotten about 2,271 neighbors.