Satellites in orbit are crucial for the day-to-day functioning of our planet, from tracking a shipment to providing live traffic updates to the internet. But as the use of satellites grows, so too do the risks. For example, a collision with a piece of debris could damage or destroy the satellite, leaving it useless. And that’s not the only threat they face.
A growing pile of space junk in orbit is also putting satellites in danger of colliding with each other. All of the junk comes from our launching satellites, and it remains in orbit until it burns up or gets knocked out of orbit by other spacecraft, solar storms, or battery explosions. At lower altitudes of a few hundred kilometers, these objects usually re-enter the atmosphere after a few years. But at higher altitudes of 36,000 kilometers, where many communications and weather satellites are located, they can remain in orbit for hundreds or thousands of years.
These satellites carry cameras and scientific sensors to gather information about the land, oceans, and air. In addition, they often point toward Earth to gather information about its climate and weather, and they can also face toward space to collect information about the Sun, the solar system, and the universe.
One of the most critical functions of satellites is providing a clear view of our global environment and allowing us to monitor environmental incidents for security, emergency response, policy, and business decisions. The loss of this functionality would be devastating to our economy and society.
Throughout geologic time, Earth has experienced natural temperature fluctuations due to changes in the Sun’s output, the tilt and position of our planet in its orbit, and the concentration of greenhouse gases. But over the past century or so, human activity is causing a more rapid change in Earth’s average temperature.
The reason is simple: Greenhouse gases, like carbon dioxide, absorb some of the outgoing energy radiation from Earth that usually bounces back into space. The extra heat absorbed causes the atmospheric temperature to increase, increasing the rate at which water vapor, clouds, and snow melt.
Nasa recently reported This “positive energy imbalance” in a study. The report noted that the positive energy imbalance had increased significantly since 2005. This figure is calculated by measuring the amount of energy entering the Earth system – such as sunlight – and how much thermal infrared radiation exits the Earth system – including some that bounce off white clouds. The difference indicates whether the Earth is gaining or losing energy. This is what drives climate change. The report said the current positive imbalance is approximately double that of 2005. The increase is alarming.
