The statement taken from the paragraph is most likely to be an opinion rather than fact is "Humans will never travel to planets around even the nearest stars. "
Explanation:
"Humans will never travel to planets around even the nearest stars" is a conclusion that the writer has made after presenting all the information that has its fundament in real data from scientific facts since all the other points are proved and presented with details that are part of astronomy studies around the world.
The definition of a convention is a meeting or assembly of people who share a common interest or a convention is a method, practice, rule or custom. An example of convention is a national meeting of English teachers
A convention, in the sense of a meeting, is a gathering of individuals who meet at an arranged place and time in order to discuss or engage in some common interest. The most common conventions are based upon industry, profession, and fandom
a way in which something is usually done. "to attract the best patrons the movie houses had to ape the conventions and the standards of theatres"
an agreement between states covering particular matters, especially one less formal than a treaty. "the convention, signed by the six states bordering on the Black Sea, aims to prevent further pollution"
Convey meaning by reinforcing, substituting for, or contradicting verbal communication. Nonverbal communication is also used to influence others and regulate conversational flow.
