The Collaborative International Dictionary
Hesperian \Hes*pe"ri*an\, a. [L. hesperius, fr. hesperus the
evening star, Gr. ? evening, ? ? the evening star. Cf.
Vesper.]
Western; being in the west; occidental. [Poetic]
--Milton.
Hesperian \Hes*pe"ri*an\, n.
A native or an inhabitant of a western country. [Poetic]
--J.
Barlow.
Hesperian \Hes*pe"ri*an\, a. (Zo["o]l.) Of or pertaining to a family of butterflies called Hesperid[ae], or skippers. -- n. Any one of the numerous species of Hesperid[ae]; a skipper.
Wikipedia
The Hesperian is a geologic system and time period on the planet Mars characterized by widespread volcanic activity and catastrophic flooding that carved immense outflow channels across the surface. The Hesperian is an intermediate and transitional period of Martian history. During the Hesperian, Mars changed from the wetter and perhaps warmer world of the Noachian to the dry, cold, and dusty planet seen today. The absolute age of the Hesperian Period is uncertain. The beginning of the period followed the end of the late heavy bombardment and probably corresponds to the start of the lunar Late Imbrian period, around 3700 million years ago (Mya). The end of the Hesperian Period is much more uncertain and could range anywhere from 3200 to 2000 Mya, with 3000 Mya being frequently cited. The Hesperian Period is roughly coincident with the Earth’s early Archean Eon.
With the decline of heavy impacts at the end of the Noachian, volcanism became the primary geologic process on Mars, producing vast plains of flood basalts and broad volcanic constructs ( highland paterae). By Hesperian times, all of the large shield volcanoes on Mars, including Olympus Mons, had begun to form. Volcanic outgassing released large amounts of sulfur dioxide (SO) and hydrogen sulfide (HS) into the atmosphere, causing a transition in the style of weathering from dominantly phyllosilicate ( clay) to sulfate mineralogy. Liquid water became more localized in extent and turned more acidic as it interacted with SO and HS to form sulfuric acid.
By the beginning of the Late Hesperian the atmosphere had probably thinned to its present density. As the planet cooled, groundwater stored in the upper crust (mega regolith) began to freeze, forming a thick cryosphere overlying a deeper zone of liquid water. Subsequent volcanic or tectonic activity occasionally fractured the cryosphere, releasing enormous quantities of deep groundwater to the surface and carving huge outflow channels. Much of this water flowed into the northern hemisphere where it probably pooled to form large transient lakes or an ice covered ocean.
Usage examples of "hesperian".
In gratitude the emperor was happy to give the Hesperians what they next asked for: permission to take a certain small number of Roman youths back to Hesperia for advanced education.
Picaro, the advances to our society that are owed to the Hesperian technology.
The steamship had entered the Hesperian Gulf, the wide arm of the North Atlantic that separated the enormous island and its smaller attendants from the continent to the west.
Only a few stands of redwoods and Atlantean pines declared that the Hesperian Gulf lay just a few miles to the west.
The same held true for island warblers, which flitted through the trees after insects like their counterparts on the far side of the Hesperian Gulf.
He could go back to his inn and wait there until it was time to enter the Hesperian embassy tonight for the I-Screen jump back to Earth.
On the west side of the square was a high wall topped with sharp spikes, with trees and a brick tower beyond: the palace of the Hesperian embassy.
Two Hesperian attendants, dressed in white linen tunics, met Pierce inside the gates.
Windhome the country rolled low for a while, then lifted in the Hesperian Hills.
A hound, of the lean heavy-jawed Hesperian breed, was the only other life in sight.
In short, they stood in a relationship to their employers quite similar to that in which the Hedins, and other Hesperian yeomen, stood to Windhome.
Austin he had always associated with his Lucy in that Hesperian palace of the West.
Maybe I had been suffering from hesperian depression or evening melancholy.
Islands to judge by the course, and one was standing out to the Hesperian Sea, which flared silver where the sun struck it and, elsewhere, ran sapphire till it purpled on northern and southern horizons.
Middle Ocean, its eastern the Hesperian Sea in the northern hemisphere and the South Ocean beyond the equator.