Just returned last night from my field trip. I found a screen shot of the About page I had taken early on the morning of the 10th July (assignment deadline). It clearly shows that there was no spelling error in the first line of text:
I still cannot understand how the error appeared but I just noticed another – on the Carl Sagan page, the last letter in ‘Correspondence’ is missing. I have no screen shot of this page before the site went live. Perhaps this one was my own fault.