Satellites

The launching of Pioneer V into its solar orbit and of Tiros, the weather observer, and Transit I-B, the beacon, brought to 13 the number of man-made vehicles still intruding on space. Ten of these are travelling around the Earth, three around the Sun. Tiros, following the most perfectly circular orbit yet achieved, and carrying television cameras and automatic positioning equipment is the first satellite adapted to systematic observation of the Earth. In Its first two days aloft it returned 1200 pictures of the Earth's cloud-cover as seen from an altitude of 450 miles. It can make and transmit 120 such pictures on each 99-minute revolution.

Still beeping after two years in space is the grapefruit-sized Vanguard I. During nearly 8000 circuits of the Earth completed by its second anniversary, it has wandered about a mile off its predicted course. This discrepancy has been traced to the pressure of sunlight.

The latest analysis of the Vanguard I orbits, shows that the earlier conclusion that the Earth is pear-shaped is not proven—a symmetrical Earth could also give rise to the observed motions.