Observers in the Nineteenth Century Reported Seeing Many Straight-Line Features

question 60

Multiple Choice

Observers in the nineteenth century reported seeing many straight-line features crisscrossing the surface of Mars and interpreted them to be canals constructed by intelligent beings. What is the MOST likely present-day explanation for these observations?

• A) The lines were rifts in the Martian surface at the boundaries of geological tectonic plates.
• B) The lines were linear, stationary cloud formations (mountain lee wave clouds) and weather fronts moving around with the planet.
• C) The lines were optical illusions caused by vague shadings on the planet's surface.
• D) The lines were groups of dark volcanoes similar to those of the Hawaiian Islands on Earth.

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Definitions:

Photosynthetic Production

The creation of organic compounds from carbon dioxide and water by plants, algae, and certain bacteria, using sunlight as an energy source, essentially the output of photosynthesis.

Ant Species

Varieties within the family Formicidae, characterized by their social organization and roles in ecosystems.

Warm Season

The period of the year characterized by higher temperatures, typically resulting in increased biological activity and growth in many organisms.

Harsh Conditions

Environmental situations that are extreme and potentially detrimental to living organisms, such as high salinity, extreme temperatures, or low oxygen levels.