Mars has an unusual atmosphere and features an outer crust comprised of rocks covered by an extremely thick layer of water-ice.
Mars is home to Olympus Mons, the tallest volcano in our solar system. Some astronomers have observed seasonal dark lines on Mars’s surface which might represent canals created by intelligent Martians – an idea championed by Percival Lowell who proposed they be made permanent through artificial means.
The discovery of Mars
Mars, the fourth planet from the Sun and first visible with naked eye, has long fascinated humanity. With its distinctive red appearance making it easy to spot from Earth, its iconic color has come to symbolize many cultures worldwide. While its exact discovery remains unclear, ancient Egyptians, Babylonians, and Greeks all recognized Mars as a celestial body at some point during its long existence.
In the 19th century, telescopes revolutionized astronomical observation. This technology permitted more detailed examination of planet Earth and its moons. Italian astronomer Giovanni Schiaparelli and American astronomer Percival Lowell both claimed they saw long canals on Mars which they believed signified civilizations or life forms; their claims, however, have since been disproven by scientific analysis.
Visual studies of Mars led to numerous discoveries, such as its 24-hour rotation period and two natural satellites. Visual examination also helped scientists establish that its atmosphere consists of predominantly nitrogen with only trace amounts of carbon dioxide and oxygen present. Finally, visual observations demonstrated that Mars does not orbit in an exact circle but instead follows an ellipse path – this finding proved pivotal to developing Isaac Newton’s theory of gravity as well as understanding solar system dynamics.
In the 1970s, spacecraft sent to Mars were used to map 85 percent of its surface and take photographs. These early missions discovered giant volcanoes and canyons, evidence that Mars experiences dust storms every so often, that its tilted on its axis is caused by iron oxide present on its surface, giving it its distinctive red hue, as well as evidence that its dust storm season occurs once every five months or so.
Recent studies of Mars have uncovered evidence of its past liquid water resources. Dry river beds hint that Mars once experienced a flowing water cycle similar to Earth, although liquid water cannot exist due to the thin atmosphere; its water ice caps cover an area that would cover 11 meters or 36 feet if melted completely.
The discovery of Phobos and Deimos
Phobos and Deimos, two natural satellites orbiting Mars, were first observed by American astronomer Asaph Hall in August of 1877 and named for two characters who accompanied Ares (Mars in Roman mythology) into battle.
Phobos is a small space rock that resembles a potato-shaped space rock in shape and color; much smaller than Earth’s Moon but darker than coal. It is covered with heavily cratered surfaces. Although its precise cause remains unknown, one theory suggests that an asteroid fragmented during collision with another object in its distant past and then got captured by Mars’ gravity could have contributed to Phobos’ unique form.
Phobos is thought to have formed from an explosion, like that caused by a meteor strike, leaving debris scattered in orbit that eventually collected to form its own moon. Finally, another possibility suggests Phobos and Deimos once formed part of Earth itself, leading to their similar composition comprising carbon-rich rocks with some water ice inclusions.
Phobos and Deimos’ discovery sparked much discussion regarding their origin. At first, many astronomers proposed the Capture Hypothesis which postulated that Phobos and Deimos may once have been D-type asteroids; this theory relied upon similarities in chemical composition as well as size between Phobos and Deimos.
Recent studies, however, have offered alternative explanations for the Martian moons. Close-up observations made by Mariner 7 in 1969 and Mariner 9 in 1971 indicate that Phobos isn’t one solid object but instead is made up of chunks held together by gravity; additionally studies of how Phobos interacts with Mars Express reveal it is not very dense.
Deimos, on the other hand, is more conventional-looking moon. Its surface is dark with only a few craters; Stickney covers six miles. Stickney features long shallow grooves radiating out from it suggesting that once flat it may have been broken by collision or been part of an orbit around Red Planet ring system.
The discovery of oceans on Mars
Telescopic observations have provided much of the research done on Mars thus far, helping scientists map its surface and locate its polar caps, while giving an idea of its climate and seasons. Unfortunately, however, no direct evidence for liquid water had ever been discovered on this distant world until now.
Scientists’ discovery of evidence for an ancient Martian ocean has revolutionized their views of Mars’ history. It rewrote scientific understandings about how water on the red planet developed over time – from trickling streams to river deltas to lakes and oceans; now scientists believe water was an integral component of early Martian history, not simply an occasional event.
Scientists have long debated whether Mars ever hosted an ocean in its lower elevation northern hemisphere, yet using topographic maps and software created by the United States Geological Survey, Cardenas and his team were able to demonstrate that it did in fact once have one using sediment accumulation evidence and sea level rise rates over large areas as evidence of Aeolis Dorsa basin filling slowly with sediment over time forming into an Aeolis Dorsa ocean basin – which they call Aeolis Dorsa for short.
Cardenas believes this to be the strongest evidence to date of an ocean existing on Mars, which would also demonstrate how conditions on its surface might have differed significantly than we originally assumed. “Had an ocean like this existed there, it would have had an immediate effect on understanding of potential life,” according to him.
Scientists hope that discovering an ocean on Mars will enable them to gain greater insight into how life began there and whether any signs of life still remain today. An ocean may also provide clues as to where to search for future signs of life on the red planet.
The discovery of canals on Mars
With the development of telescopes, Mars quickly became a favorite target of astronomers who trained their lenses upon its pale disk. Numerous drawings were produced documenting what was seen through these lenses; but what most amazed them were dark lines on Mars’ surface that later came to be understood as canals, sparking widespread scientific discussions regarding “watery” Mars.
Italian astronomer Giovanni Schiaparelli first noticed these dark streaks on Mars in 1877 and created an accurate map for that time. He called these lines “canali,” not canals as this term suggested waterways in English-speaking astronomers’ minds; American Percival Lowell was among those early advocates for an ecofriendly Mars.
Lowell wrote a bestseller entitled Mars that sold well and funded his own observatory in Flagstaff, Arizona where he conducted observations to support his theories. Lowell was an enthusiastic and imaginative individual; however, his interpretations of what he saw on Mars often alienated his assistants and even Schiaparelli himself.
Mars had long been thought to be in an advanced stage of evolution compared to Earth, which would explain its canal systems. His theory gained further support upon discovering Phobos and Deimos as moons provided further proof that intelligent life existed on Mars.
Mars fever reached an all-time high during the 1930s. Orson Welles took full advantage of public fascination with Mars’ canals with his radio drama War of the Worlds, depicting an imagined Martian invasion. By 1907, most astronomers thought these features were optical illusions but continued speculation on them; Mariner 4’s flyby of Mars proved otherwise; many modern astronomers believe these canals likely resulted from dust movement on its surface rather than alien invasion.