TIROS 1: The First Weather Satellite and Its Fuzzy First Images

TIROS 1, the world's first meteorological satellite, was launched in 1960, only two years after the first successful American satellite in 1958. It now hangs in the One World Connected Gallery at the National Air and Space Museum, where curator Teasel Muir-Harmony, part of the team that designed the gallery, describes what it proved: that satellites could be useful tools for predicting the weather and tracking weather systems on Earth.

The satellite

From the outside, TIROS 1 shows little. Over 9,000 solar cells help charge its batteries. An antenna sent signals to Earth, and a receiver took signals from Earth stations. There were two television cameras, one wide-field and one narrow-field, much of them inside the satellite.

By today's standards it was not advanced, but it was the first in a series of TIROS satellites, each building on the knowledge of the previous one. Its initial images showed only so much, yet they taught NASA engineers and scientists a great deal about what a successful weather-prediction satellite would need. When it flew, it was the beginning of the Space Age, and little was known about how satellites would help life on Earth. Weather prediction was one early idea.

Reading the first images

Steve Nesbitt, head of the Department of Climate, Meteorology, and Atmospheric Sciences at the University of Illinois Urbana-Champaign, examined some of the first images in the museum's archives. They are visible-light pictures from a television camera looking down. On the left he sees high clouds, probably a jet stream. On the right are low puffy stratocumulus clouds, common in the tropics. For meteorologists, he says, nobody had seen this before, and it was a revolution.

The pictures carried no maps, latitude or longitude, so placing them meant guessing. Nesbitt recognized the Red Sea, Egypt and the Nile River, and the Middle East and Israel.

From photos to a global picture

Images were transmitted to Earth, then processed, which was not quick. One display is an assembly of individual photos printed and pasted together on a world map, lined up with coastlines, the equator and the continents. Nesbitt calls it as analog as you get, and the first time global clouds could be seen. Before then, meteorologists knew cloud patterns only from the ground. Stitching them together at the same time everywhere was a revolution in forecasting.

Forecasting then and now

In the TIROS era, forecasts relied on weather balloons and surface observations, which exist only over land, leaving a huge gap over the ocean. Today measurements are continuous, and with more computer power forecasts reach neighborhood scale out to 7 days, where once a nation could be forecast only one or two days ahead.