Vanguard TV5

The goal Vanguard TV5 satellite, Vanguard 2A, was to measure the X-ray emission from the sun and its effects on the Earth's atmosphere. This was the same test as Vanguard Lyman-alpha satellites but at different wavelengths. The detectors were two identical ionization chambers sensitive to X-ray wavelengths produced in solar flares (2 to 8 Å, or 200 to 800 pm). The ionization chambers were located 120 deg apart in the equatorial plane of the satellite and received a maximum signal when an ion chamber tube "looked" toward the sun. The instrumentation measured the 1 to 8 Å (100 to 800 pm) X-ray flux, and recorded the peak solar flare intensity by means of a peak-reading memory device, during the daylight portion of each orbit.