Changes in Lit Area in the Yellow River Zone, Inner Mongolia Autonomous Region, 1992-2003:

...dramatic changes in Urban Area in Northern China Night-Time Lights from the Defense Meteorological Satellite Program's
Operational Linescan System (OLS) instrument. A 2007 conference paper on these results is here (PDF) (English text .... Chinese text)

In the animated map below, the longitudinal extent is about 630 kilometers (~400 miles)

In the static maps below, the longitudinal extent is about 644 kilometers (~400 miles)

1992 layers :

2003 layers :

Change image (red is increased area, green is decreased area of stable lights, white is no change, light blue is mapped "urban areas" from a pre-1990 map):