国家国防科技工业局日前宣布，经过6个月的在轨测试后，我国首颗高轨遥感卫星“高分四号”正式投入使用。

Gaofen-4 is China's first geosynchronous orbit high-definition optical imaging satellite and the world's most sophisticated.

“高分四号”是我国首颗地球同步轨道高分辨率光学成像卫星，也是世界上精度最高的卫星。

Unlike from Gaofen-1 and Gaofen-2 in low orbits around the earth, Gaofen-4 is orbiting at 36,000 kilometers. High orbit satellites have the advantage of being able to snap "grand scenarios." Low orbit satellites, in contrast, can see more detail at faster speed.

不同于“高分一号”和“高分二号”在低轨道绕地球旋转，“高分四号”是运行在距地36000公里的轨道上。高轨道卫星能够捕捉“更宏观场景”的优势。相反，低轨道卫星可以以更快的速度看到更多的细节。

国产高分四号卫星正式投入使用 分辨率世界最高

Low orbit satellites cannot always follow natural disasters, but Gaofen-4 can continuously observe a disaster because it moves synchronously with the earth. It improves the response to disasters like earthquakes, landslides and typhoons with its high-precision sensors.

低轨道卫星不能一直监测自然灾害，但是由于与地球同步移动，“高分四号”则可以持续对灾害进行监测。因采用高精度传感器，该卫星还可缩短对地震、泥石流和台风等灾害的响应时间。

Gaofen-4, which was launched in December 2015, has a designed lifespan of eight years, compared to other remote sensing satellites which remain in service for less than three to five years.

“高分四号”于去年12月发射升空，其设计寿命为8年，相比之下，目前仍在服务的其他几颗遥感卫星的设计寿命不足3-5年。

During the in-orbit test, Gaofen-4 has been used to collect imageries of flood-hit areas in south China and monitor fires that occurred in southwest China's Sichuan Province and in Russia.

在在轨测试期间，“高分四号”已被用来收集中国南方遭受水灾的地区的影像，并监测发生在中国西南的四川省以及俄罗斯的火灾。

China started the Gaofen project with the launch of Gaofen-1 in April 2013. It aims to launch seven high-definition observation satellites before 2020, designed for disaster prevention, surveillance of geological disasters and forest disasters and weather forecast.

我国于2013年4月发射“高分1号”，以此拉开了“高分卫星”项目的序幕。该项目的目标是在2020年之前发射7个高分辨率观测卫星，专为防灾、地质灾害监测、森林灾害监测和天气预报而设计。