A Chinese satellite, Tiangong-1, fell into the earth very recently.
Fortunately, it dropped into the Pacific Ocean harmlessly. But I feel fearful to imagine that it is approaching Tokyo city. Indeed, it is almost impossible to control the rendezvous point of falling satellite.
There is already a large amount of space debris. Developed countries have been eager to rocket satellites since the mid 20th centuries. And now, researchers are arguing about the adverse influence of debris in the future.
The Strait Times: Chinese satellite Tiangong-1 crashes back to Earth: 5 things you need to know about space junk
I believe the risk of space debris is very limited now. And it makes us difficult to become serious about this issue. It is a common feature of the environmental issues. Nowadays, space is the last frontier of the human being. We should be responsible for establishing the international rules for sustainable use of the space.