The most straightforward way to start whittling down the possibilities is to focus on the two most tangible items cited:
- the photo itself (as a physical artifact that ended up in the National Archives), and
- the ship in the background, alleged to be the Japanese vessel
Koshu.
On the photo front, the first thing is to check any logs or catalogues for reference points on this particular photo. I have yet to read any article on this latest claim that specifies what, or how much, was done in this regard.
The ship in the new (-ly publicized) photo is claimed to be named
Koshu. The
Koshu was a Japanese oceanographic / survey vessel. This photo:
SOURCE:
https://earharttruth.files.wordpress.com/2015/01/koshu-circa-1918.jpg
... is purported to be a picture of
Koshu circa 1918. This earlier photo appears generally consistent with the vessel in the currently-publicized photo to my eye.
I find it interesting that this photo from two decades earlier shows
Koshu towing(?) what seems to be the same smaller craft one sees in the new photo - the craft that is purported to be a barge carrying the Electra. It makes sense to me that a survey ship would travel with a sizable satellite craft.
This vessel shouldn't be confused with the freighter Koshu Maru, which was Lloyd's-registered under its inaugural name Teishu Maru as of 1937 (the same year as its entry into service). The name apparently changed once the vessel was turned over to the IJA (Imperial Japanese Army) for / during WWII. This freighter was sunk in 1944 while carrying POW's in the area of Java(?).
Citing research originally done by a Vincent Loomis, this blog page:
https://earharttruth.wordpress.com/tag/koshu/
... claims
Koshu was at Ponape on July 2, 1937, set out for the Marshalls on July 6, reached Jaluit on July 13, re-coaled and headed for Mili on July 14, and returned to Jaluit on July 19.
If subsequent info indicates this photo dates earlier than July 13 it can't be Earhart / Noonan plus
Koshu, because
Koshu hadn't reached Jaluit yet.