text: The Sun's Travels and Why Fall is Nigh (SPACE.com) SPACE.com - Wednesday, Sept. 22 marks what scientists call the fall equinox in the Northern \  Hemisphere, when night and day are of equal length and cooler weather is on \  the way -- if it hasn't already arrived.
inputs: The Sun's Travels and Why Fall is Nigh (SPACE.com) SPACE.com - Wednesday, Sept. 22 marks what scientists call the fall equinox in the Northern \  Hemisphere, when night and day are of equal length and cooler weather is on \  the way -- if it hasn't already arrived.