following pdf file contains the resized Project Blue Book
document below and is now housed on the NICAP site for security
The original over-sized doc from the Blue Book site is listed below:
July 23, 1952; Fragment / Found where map shows the Saucers have been observed on July 20 and 26, 1952, between Herndon, VA, and Washington, D.C. The map shows sightings near Vienna, Virginia. This is where the 'Alvin Moore' "Fragment" was found.
I was just checking the maps for that area and those tracks shown on the newspaper article take the saucers very near the Pentagon at Arlington, VA. then on to Boiling AFB and if you continue, on to Andrews AFB. I think this may have been a show of force, the Shot Across The Bow.
Compare to Paragraph 24 part (a), on page 7 of this document at the bottom of page.
MEMORANDUM 8 August 1952
From: Comdr. Alvin Edward Moore, USNR
To: Captain Edward J. Ruppelt, USAF, Head, "Operation Blue Book,"
Wright-Patterson Air Force Base
Subj: The discovery and preliminary investigation of a stone-like object,
which apparently fell from from the air near Washington, D. C.