Vanguard 1 Celebrates 50 Years In Space, Forgets To Phone Home
By James Grahame
Even though it was the fourth man-made satellite successfully launched into space, Vanguard 1 has earned a special place in history as the oldest spacecraft in orbit. The shiny 1.47kg (3.2lb) spherical spacecraft was launched from Cape Canaveral, Florida on March 17, 1958. Scientists originally believed it would remain in orbit for several thousand years, but solar radiation and atmospheric drag have reduced its off-world vacation to about 240 years.
America's second successful satellite (an earlier failed Vanguard Project launch was dubbed 'Flopnik' by thre press) was equipped with two radio transmitters, including the first solar powered transmitter to reach space. The primary battery powered transmitter lasted until the batteries were exhausted in June 1958, while the solar equipped radio remained operational until May 1964. Vanguard now orbits the earth silently once every 132.4 minutes and has traveled a whopping 10 billion kilometers over its lifetime.
Vanguard 1's rudimentary transmitters enabled researchers to determine that the earth was slightly pear shaped. It had a diameter of only 16.5 cm (6.44 inches), causing Soviet leader Nikita Khrushchev to dismiss it as "the grapefruit satellite." Still, Vanguard's successful launch into a permanent orbit using a three-stage rocket and its pioneering use of solar technology were indeed vanguards of things to come.