However, after some research, it is possible these were naval target balloons, and the USS Trepang was conducting a weapons test of some kind. As indicated and referenced/sourced above, "From 22 February to 22 March [1971], the nuclear attack submarine operated beneath the northern ice cap, conducting extensive tests to provide data for her weapons systems, as well as carrying out scientific experiments concerning the movement, composition, and geological history of the cap itself."
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n July 12th, 2015, another updated was released by Alex Mistretta, working with Steve Murillo:
Steve spoke with the Admiral Dean R Sackett and I have been in touch with John Klika, both named by the source who released the pictures as principal participants in this saga. Both men were indeed on the Trepang SSN 674, in March of 1971 in the Arctic. Admiral Sackett denied seen anything unusual while onboard the Trepang. He gracefully took two phone calls from Steve and checked out the pictures that we sent him privately. He could not identify what was in the pictures. John Klika also confirmed that he was also on the Trepang in March of 1971, but told me that neither himself or anyone else saw anything unusual while in the Arctic. He found the investigation interesting reading, and doesn't know what the pictures represent. I believe them. I feel confident in saying the Trepang was not involved in the taking of the photographs. The photographs remain a mystery, no doubt. This investigation is far from over. The veracity, or lack off, of the photographs themselves is partly removed from the location and said provenance. They may be authentic and highly unsual, or they may be more mundane objects that in time I will identify. Furthermore, there is the issue of provenance, which is unknown. Are they really from the Arctic, and from an American sub? On the later point, there was another sub in the region, just a month before the Trepang, and that is the USS Skate USN 578. Ergo, the investigation continues.