It is not crazy in astrobiology circles these days to hold the opinion that the life that now envelops Earth started on Mars and then some pilgrim microbe was brought here on an errant asteroid. We know now that the sky is an endless conveyor belt with cosmic riffraff shuffling debris from planet to planet, even star to star, as personified by Oumuamua, the wandering comet from outside our solar system that cruised blithely through the planets last winter. In the fullness of time, everything gets everywhere.

[Sign up to get reminders for space and astronomy events on your calendar.]

We could all be Martians, then, which could help explain the seemingly endless lure of the Red Planet. The dream of the exile to return to what might once have been Eden. Elon Musk has said he wants to die there, but he’s not r ead y to go there quite yet.

I grew up terrified as well as curious about the place, after I saw the previews of “Invaders From Mars.” The film showed a boy my age seeing a flying saucer go under a hillside, after which the townspeople, including his parents, were kidnapped and turned into robots. My parents never let me see the whole movie.

It paid homage to a part of a mythology that dated to the beginning of the century, of Mars being the dying home of a dying civilization of super smart beings — little green men — hunkered by canals bringing water from the poles. Those visions sprang from a misunderstanding of the work of the Italian astronomer Giovanni Schiaparelli, who in 1877 thought he saw long, thin lines he called canali, (channels in Italian) lacing the surface of Mars. Percival Lowell, a socialite and astronomer took the notion seriously and proceeded to map what he thought were cities and canals on the planet.