Tiros 1 was launched on April 1, 1960. TIROS I was designed to test experimental techniques for taking television footage of weather patterns from an almost circular orbit, at an altitude ranging from to . Though operational for only 78 days (15 days fewer than planned), it was vastly more successful than Vanguard 2 in demonstrating that satellites were useful for surveying atmospheric conditions from space and in sending back 22,952 images.
TIROS I was tall and in diameter. Two television cameras were housed in the craft, along with two magnetic tape recorders which could be used to store photographs when the satellite was out of communications range. Power was supplied by onboard batteries, charged by 9200 solar cells.