June 2, 2025
TOKYO – Satellites orbiting the Earth are essential for weather forecasting, broadcasting and even for locating people. The “eyes” that view the planet from space now have such high resolution that they can boast tremendous capabilities in aiding efficient management of dairy farms and post-disaster recovery and restoration.
GRAPHICS: THE YOMIURI SHIMBUN
Japan’s first satellite was Ohsumi. It was launched in 1970 by a team from a research institute at the University of Tokyo.
A little over half a century later, many types of satellite are indispensable in our daily lives, including earth observation satellites for weather forecasting; communications and broadcasting satellites essential for transmitting data such as TV signals; and positioning satellites for determining the positions of cars and others. They are also used for military purposes such as detecting missiles.
Early satellites could at best be used to distinguish whether land on the Earth was an agricultural field or a residential area. Technology in modern satellites has evolved to the point where the type of a vehicle on a road can be identified, and the risk of a water pipe leak can be calculated based on ground surface temperature and ground deformation.
‘Space Cattle’ project
As beef cattle graze peacefully on a farm in Shiraoi, Hokkaido, their conditions are managed using satellite data as part of the “Space Cattle” research project conducted by Hokkaido University and Keio University in collaboration with livestock farmers.
Devices attached to the cattle’s necks receive radio waves emitted from a satellite system to monitor their positions and determine the distances they have traveled in a vast pasture. The system can detect if any individual is not getting enough physical activities. Its use is expected to reduce the number of cattle that get lost and die.
Lower burden on farmers
The satellite system can also provide images for the monitoring of the growth of grass in the pasture. If the cattle have grazed too much in one area, they can be moved to another area where there is more grass. By guiding them efficiently in this way, farmers do not have to rely as much on imported feed, the price of which soars in spring and summer.
“I want to encourage young people to get involved in raising livestock,” Prof. Takafumi Goto, of Hokkaido University said enthusiastically. Goto is one of the specialists engaged in the “Space Cattle” project.
Livestock farmers are required to care for their animals on a daily basis. Goto has seen many students who were eager to become livestock farmers eventually change their career paths upon graduating.
If grazing data collected from space can be checked via smartphone, livestock farmers will be able to take relaxing family trips. That is one of Goto’s goals. He also says that grazing cattle on abandoned farmland is another goal. In this way, the “Space Cattle” project has enormous potential.
Satellites can also help crop farmers and fishermen. Their images can be used to monitor the growth of rice plants and determine the proper amount of fertilizer to apply and the proper time to harvest. Plankton levels and seawater temperatures can be monitored to predict good fishing grounds and adjust feed in aquaculture.
Used for disaster efforts
Satellites are also a powerful tool in disaster recovery efforts.
After last year’s Noto Peninsula Earthquake, satellite images captured the widespread upheavals along the coastline and landslides in mountainous areas, providing a full picture of the damage. Satellite communications were used in areas that became isolated as cell phone base stations were not operational.
They are also useful for disaster prevention.
In Atami, Shizuoka Prefecture, where 28 people were killed in a mudslide in 2021, a satellite system monitors for the unauthorized logging of forests. The Tokyo Metropolitan Government uses a satellite system to identify dangerous embankments of earth.
“The use of satellite data will expand in all fields in the future,” said Naohiko Kohtake, a professor at Keio University who is an expert on space development. “It also has the potential to solve problems related to labor shortages and depopulation, and to create new industries.”