The report is being made public because of a provision inserted by Senator Marco Rubio of Florida, the top Republican on the Senate Intelligence Committee, into a huge spending bill passed by Congress.

“This report is an important first step in cataloging these incidents, but it is just a first step,” Mr. Rubio said in a statement. “The Defense Department and Intelligence Community have a lot of work to do before we can actually understand whether these aerial threats present a serious national security concern.”

Of the incidents examined by the task force, there are “no clear indications that there is any nonterrestrial explanation” for them, said a senior official, adding that the government would “go wherever the data takes us” as the inquiry continued.

The report avoids any real discussion of the possibility the unexplained phenomenon are extraterrestrial in nature. It was not the purpose of the government’s task force to search for extraterrestrial life, a responsibility that falls to NASA, said a senior governmental official.

Perhaps as a result, government officials said that going forward they would only focus on making observations of the phenomena and had no plans to try to communicate with the objects.

Government officials said that on further examination, the 21 reports that show unusual acceleration or movement could prove to have normal explanations. Government analysts have scrutinized the cameras and sensors that recorded the phenomena for potential flaws, a senior government official said.

There are plausible, but dry, explanations for each of the Navy recordings that are more likely than some sort of extraordinary technology, said Mick West, a science writer who focuses on debunking conspiracy theories.

“If you just say, ‘Oh, it’s aliens,’ that’s actually quite a simple explanation,” Mr. West said. “The actual explanation is kind of complicated, which is why a lot of people miss it. But yet the mundane explanations exist for all of these videos.”

The Pentagon and the Office of the Director of National Intelligence are considering research and development programs that could improve and standardize data collection, the officials said. With more data, better pattern analysis of the episodes could be done, said a senior government official.

This content was originally published here.