The source of the Yangtze fascinated but eluded generations of Chinese living along the lower reaches of the river. Western explorers of the 19th and 20th Century also found it illusive. Up until the Ming Dynasty in the 14th to 17th Century, the river was thought to originate from the Min River of Sichuan. It was the Ming scholar explorer Xu Xiake (1587-1641) who successfully traced the upper reaches to the Jinsha River, the correct upper tributary of the Yangtze. Geographers in the Qing Dynasty (1644 – 1911) further identified the Tongtian He which flows into the Jinsha. It wasn’t until 1976 that PRC geographers defined the Yangtze source as originating from Tuotuohe high up in western Qinghai Province.

However, this finding was still erroneous. Wong How Man and CERS made multiple attempts and finally defined what is now recognized as the scientific, geographic and officially accepted source of the mighty Yangtze River, third longest river in the world.

32°36'14"N 94°30'44"E, 5,170 m above sea level, 13:15 15 June 2005

Between 1985 and 1986, Wong How Man led a National Geographic Expedition studying the entire Yangtze River from mouth to source. His team arrived at Jianggendiru glacier of Geladandong Mountain, which was defined by China’s geographers as the river’s source in 1976. The glacier is the source of the Tuotuohe, one of three main tributaries of the upper Yangtze.

Wong How Man used satellite images (MSS and TM data), Shuttle Image Radar (SIR-A and SIR-B) as well as Large Format Camera (LFC) on the Space Shuttle to explore and define a newer and longer source, that of Dam Qu, another tributary of the Tongtian He. His team reached a main source of Dam Qu at the high-elevation basin of Kaxigong on September 3, 1985. Results of this expedition were subsequently published as a book, magazine articles, as well as in a journal of the Institute of Geography in Beijing. Film footage was also released, including a short feature on Discovery Channel.

In the summer of 1995, Wong led a CERS team including several geographers from China and revisited the Dam Qu source he had established in 1985. Following this expedition, a map of the source area was prepared, and more articles released.

In 2005, with the latest and higher-resolution satellite images on hand, Wong, with the help of NASA scientist Martin Ruzek, realized that there was a longer tributary of the Dam Qu. In earlier space images a section of the upper reaches was hidden by cloud cover. A large-scale international expedition involving 24 members, including geographer, remote sensing expert, biologist, anthropologist, expedition doctor, car mechanic, support staff and two film crews, was organized to tackle this newer source.

After much efforts, the multidisciplinary expedition force reached Jashigela, a snow peak, with its melting snow stream adding 2.4 kilometers to the length of the Yangtze River over the previous source established by Wong in 1985 and 1995. Today, this new source is recognized as the real source of the Yangtze.