用Python脚本从NASA上下载卫星照片

网上找这段脚本，尽然可以下载卫星照片，根据这段代码的思路应该可以写出更多有用的脚本：

#! /usr/bin/env python

import urllib

SAT_ZOOM_LEVEL = 0.0001389 #Like in request form

def retrieveImage(coordinates, image_size, name):
 """Retrieve satellite images from the Nasa's site"""
 request1 = "http://onearth.jpl.nasa.gov/landsat.cgi?"   
                 "zoom=%f&x0=%f&y0=%f&x=%i&y=%i&action=pan&layer=modis%%252Cglobal_mosaic&pwidth=%i&pheight=%i" %  
 (SAT_ZOOM_LEVEL,
  coordinates[0],
  coordinates[1],
  image_size[0]/2,
  image_size[1]/2,
  image_size[0],
  image_size[1])
 for line in urllib.urlopen(request1):
  if line.startswith("<td align=left><input type=image src="):
   request2 = "http://onearth.jpl.nasa.gov/%s" % (line.split("\"")[1],)
   break
 urllib.urlretrieve(request2, name)

if __name__ == '__main__':
 retrieveImage((60.7376856, 56.5757572), (800,600), "test.jpg")
 # Specified coordinates is the point accurately at the image center