peter martinez who is in charge of the issue said private firms around the world are expected to launch more satellites. he stressed the need to develop technology to prevent defunct satellites from becoming waste. an official from japan's foreign ministry said each country tackling the issue on its own won't work. he said multi-national coordination is indispensablind. there's concern it won't be safe. >>> march 11 marked six years since a massive earthquake and tsunami hit northeastern japan. today we start our series about challenges that people in fukushima are confronting. the japanese government is lifting evacuation orders for some municipalities this month, while the decontamination work for these places is finished, radiation fears persist. former residents are being left with a difficult choice, try to move back home, or stay away. nhk has the story of one couple's decision. >> reporter: this may be a house, but it's no longer a home since the terrible disaster six years ago. >> translator: when my grandson used to come here, we would play together in a small kids pool and the