3/12/021 Old Mars Mars is further away, we see a smaller image so we need much better telescopes

3/12/022 Mars Reddish color, easily seen with naked eye –on Earth, red colored rocks are found in deserts Roman god of war color of blood (second to Jupiter) Astrological symbol is a shield and spear

3/12/023 Until photography, all images drawn or painted very difficult to compare observations - intervention of the observer first image due to Fontana (1636)

3/12/024 Refractor telescopes Simple refractor not a sharp image colors have a different focus

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6 First accurate drawing - Huygens 1659 first showing of polar caps Huygens 1672 Mars was seem to have dark and light areas –Dark – water (oceans, seas, bays lakes) –Bright – continents (reddish color)

3/12/027 Syrtis Major

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3/12/029 Herschel observed tilt to be ~30 degrees (like Earth) therefore, 4 seasons (like Earth) concluded that the inhabitants would enjoy a life similar to that on Earth

3/12/0210 Big improvement Invention of the achromatic objective lens Chester Hall, 1729 Two different kinds of glass in the objective

3/12/0211 Problems with glass 1799 Swiss, Pierre Louis Guinand cast high quality lenses as large as 6” worked with Joseph von Fraunhofer, a German optician who did the grinding and polishing later lenses were much larger

3/12/0212 Applications of new telescopes Heinrick Mädler - school teacher (seminary), amateur astronomer met Wilhelm Beer - banker and amateur astronomer looked at Mars (map in 1830) did not name features mapped Moon

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3/12/0214 More observations Mountains of Mitchell, 1845 (B & M) use of the term canale; Angel Secchi, 1858 (referred to a channel) Dawes, 1860s, names features –also determines relation between size of telescope and resolution –begins a race for big telescopes No standard nomenclature

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3/12/0216 Next opposition 1877 new telescope (Alvan Clark) 26” at US Naval Observatory new observer; Asaph Hall not a professional astronomer observed two satellites; Phobos (fear) and Deimos (flight) - reference to Iliad only terrestrial planet (except Earth) with satellites

3/12/0217 At the same opposition Giovanni Schiaparelli accurate measurements of lat. & long. of features introduced a nomenclature that stuck (1877) showed long, straight, narrow dark makings called them canali, again meaning channels got translated into canals, artificial

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3/12/0219 New features Schiaparelli - observed gemination, a splitting of canals canals had to be several miles wide to be seen must have been vegetation on the banks of the canals showed dark areas where canals crossed

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3/12/0221 Names Light areas - terrestrial or imaginary lands –Arabia, Hellas, Syria, Amazonis dark areas - bodies of water –seas - Tyrrhenum mare –bays - Sabaeus sinus –gulfs - Golfo sabeo –lakes - Solis lacus

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3/12/0223 Problems in viewing Mars Opposition every 2 years and 50 days best oppositions every 15 or 17 years difficult image at opposition next (great) opposition: August 28, 2003 –Best in thousands of years!

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3/12/0227 New player Percival Lowell an amateur but a serious one was convinced that the canals were artificial constructed to irrigate deserts (red color) view of Mars as a planet drying out Dark areas were not seas but marshes Wave of darkening (primary evidence)

3/12/0228 If there is water on Mars Dark areas, light areas (yes) clouds (yes) storms (yes) reflection of Sun on water (no) –Reflected light not polarized (no) –but suppose the dark areas are vegetation polar caps (yes) red color (yes)

3/12/0229 Implications of water On Earth, water comes from volcanic activity volcanoes indicate geologic activity volcanoes indicate plate tectonics moderate temp. & atmospheric pressure as we understand it, life can form under these conditions

3/12/0230 General conclusions, 1877 Moderate climate water available large desert areas planet losing water an ideal place for life sentient organisms living there

3/12/0231 Requirements for life Moderate temperatures (between 0 and 100 C) free water an atmosphere –does not have to be oxygen