Journey to the history of Nimbus weather satellites

Nimbus satellites have collected many important meteorological data and created major turning points in the history of science.

In August 1964, the first Nimbus satellite was launched into space, paving the way for a series of satellites to observe Earth later. Nimbus-1 weighs 374kg, is the first test for modern meteorological research devices.

People call this satellite "Butterfly" because two large solar panels look like butterfly wings. Nimbus-1 is equipped with the most advanced imaging systems of the time.

Nimbus satellite marked a major turning point in meteorology.(Photo: NASA).

Nimbus satellites have created "first" brands in the history of science, such as for the first time capturing images of the storm from the universe, mapping the distribution of births for the first time. photosynthesis, for the first time demonstrated the technology to monitor the movement of people, animals and objects on Earth via satellites.

The data that Nimbus collected also allows scientists to develop programs that are capable of forecasting the weather before one, even two weeks, which were almost impossible. The ability to forecast long-term weather saves more than $ 2 billion per year for many industries such as transport or seafood, according to the US National Research Council.

"Nimbus left a big mark in the meteorology industry that still exists today. It measures air temperature, wind and rain. Nimbus helps the field of weather forecast boom , " Ralph Shapiro, executive manager of Nimbus satellites, praised.

However the journey of the first satellite is very short. Just one month after Nimbus-1 was in orbit, the solar panel failed so the satellite could not continue to function. On September 22, 1964, the mission of Nimbus-1 ended.

Although the first journey is not long, the data obtained is impressive and plentiful. That information proved the power and potential of meteorological satellites. After Nimbus-1 ceased operations, Goddard Space Flight Center planned to continue Nimbus's mission.

Satellite Nimbus recorded storm images from above.(Photo: NASA).

On May 15, 1966, the second Nimbus satellite continued to be launched from California, USA. However, a serious accident happened to the third Nimbus satellite, Nimbus-B.

Similar to Nimbus-1 , Nimbus-B has a butterfly-like shape with large solar panels on both sides. It is also equipped with an additional energy source that was only used for military aircraft at the time, it was RTG radioisotope thermoelectric generator. RTG with radioactive pluton-238 generates electricity about 50 W, which helps the satellite operate for another year after the solar cell stops.

Scientists launched Nimbus-B on May 18, 1968 from California. However, when Nimbus-B left the launch pad and was flying south, across the Pacific Ocean, the problem occurred. The satellite began to deflect and plunged toward the mainland.

The safety officer immediately presses the button to activate the self-destruct device. Nimbus-B brought two nuclear power generators and millions of dollars of scientific equipment exploded and crashed into the sea. It exploded only 150km from the crowded residential area of ​​Los Angeles.

The journey of Nimbus-B lasted only 120.8 seconds.

All project members are extremely upset by the incident."Hundreds of people have put their hearts and hearts into this program. It is a great emotional shock for many people," said Isaiah Sheldon Haas, an engineer involved in the Nimbus project.

Experts at NASA began investigating the cause of the failure. The NASA report, released in October 1968, said the satellite had a problem because the gyroscope, the satellite navigation device, had been installed incorrectly.

According to Shapiro, it all depends on a small metal shaft, called a positioning pin, to mark the correct direction of rotation. But an incident occurs with the positioning pin when the test engineer turns it, making it rotate 90 degrees wrong. This mistake has caused the satellite to deviate from its orbit.

Nimbus-B explodes and sinks to the bottom of the sea.(Photo: NASA).

Meanwhile, people continue to search for fragments of Nimbus-B with the main goal of regaining the nuclear energy generator. Those in charge of pledging the fuel box will keep radiation from the pluton-238 core inside, but radioactive isotopes emit alpha radiation at risk of causing cancer so they don't want to leave them under the sea. Moreover, RTG is worth millions of dollars.

On September 30, submarines locate some fragments of Nimbus-B, but the search for nuclear power continues. On October 9, 1968, after months of searching and costing about $ 200,000, a group of divers and submersibles salvaged them successfully from the seabed.

While the search and salvage of undersea satellites took place, Nimbus' task force also planned for the next steps.

Researchers, scientists, mechanics, engineers and many others have worked together for nearly 10 years."They built the equipment, we installed it in the satellite, launched it and then it plunged into the sea. What will you do next?" , Haas said. The answer is "to try again".

Haas first checked the test program for satellite control systems. He immediately discovered a problem: No spare parts. New satellites are equipped with spare parts to control pluton-238 nuclear core re-use and control systems, which cost about $ 20 million.

On April 14, 1969, 11 months after the defeat of Nimbus-B, Nimbus-B2 was launched into space, becoming the third Nimbus satellite to orbit the Earth. Nimbus-B2 succeeded in collecting new data, helping scientists for the first time obtain detailed information about atmospheric fluctuations.

Mission Nimbus is only a small part of the countless achievements of space science. However, the Nimbus satellites and thousands of people involved in the fabrication, testing and tracking of each of their movements in the universe have contributed to the development of satellite technology and meteorological industry.