Weather satellite of rotation and its elliptical orbit kept it from collecting a notable amount of useful data. The Explorer VI and VII satellites also contained weather-related experiments. The first weather satellite to be considered a success was TIROS-1, launched by NASA on April 1, 1960. TIROS operated for 78 days and proved to be much more successful than Vanguard 2. TIROS paved the way for the Nimbus program, whose technology and findings are the heritage of most of the Earth-observing satellites NASA and NOAA have launched since then. Beginning with the Nimbus 3 satellite in 1969, temperature information through the tropospheric
Paz (satellite) Paz (satellite) Paz (Spanish for "peace") is a Spanish Earth observation and reconnaissance satellite launched on 22 February 2018. It is Spain's first spy satellite. The satellite is operated by Hisdesat. "Paz" was previously referred to as SEOSAR (Satélite Español de Observación SAR). For observational purposes, "Paz" uses a synthetic aperture radar (SAR) to collect images of Earth for governmental and commercial use, as well as other ship tracking and weather sensors, which enables high-resolution mapping of large geographical areas at day and night. The X-band radar imaging payload operates at a wavelength of , or a frequency of 9.65