1 / 25

Mars

Mars. ASTR-3040 Astrobiology Day 18. Homework. Chapter 8 Due Thurs. March 31 3, 7, 13, 23, 30, 32, 41, 46, 51, 52 Plus (49 or 50) if you've read one of the books or seen one of the movies. Civilization. Mars holds a special place in human fantasies about space and aliens.

zelig
Télécharger la présentation

Mars

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Mars ASTR-3040 Astrobiology Day 18

  2. Homework • Chapter 8 • Due Thurs. March 31 • 3, 7, 13, 23, 30, 32, 41, 46, 51, 52 • Plus (49 or 50) if you've read one of the books or seen one of the movies.

  3. Civilization • Mars holds a special place in human fantasies about space and aliens. • Herschels (lae 1700s)‏ • Schiaparelli (1877)‏ • Lowell (1895)‏ • Canals • civilizations

  4. Literature • H.G. Wells – War of the Worlds (1898)‏ • ER Burroughs • Ray Bradbury

  5. Movies • Capricorn 1 • Total Recall • The Ghosts of Mars • Mars Attacks

  6. Exploration of Mars • http://en.wikipedia.org/wiki/Exploration_of_Mars

  7. Modern View • Began in the late 1960s – Mariner 4, 6, 7 • Dust storms, volcanoes, craters • First landers – Vikings – 1976 • No hard evidence of life, weather station, no liquid surface water.

  8. Seasons 25 degree tilt vs. 23.5 for Earth 0.093 orbital eccentricity 1.38 – 1.66 AU Strong winds driven by seasonal changes (temperature gradients)‏

  9. HST monitoring program Mars Global Surveyor Polar caps – change with seasons Water ice and Carbon Dioxide ice Phoenix lander (N. Pole) confirmed water ice.

  10. Dust Storms HST monitoring program Dust Devils – Spirit rover

  11. Geological History • Volcanoes • Big, shield type • Recent evidence of underground water • Flowing water? • Resurfacing in North

  12. Surface evidence of water in the past. Pathfinder landed in what appears to be a floodplain. Spirit – Gustev crater – an ancient lake? Opportunity – rock structures are only seen in standing water environments on Earth (“blueberries”).

  13. Opportunity – rock structures are only seen in standing water environments on Earth (“blueberries”). Mars Express orbiter images - floodwaters?

  14. Flood channel? Water-carved channels on slopes of volcanoes. Hadriaca Patera (center).

  15. Mars Water Today Relief map. Was the entire northern hemisphere an ocean at one time? Blue is below “sea level”. Hydrogen content map. Blue is highest hydrogen area. Maybe the top meter or so contains water ice. Distributed mostly in the polar regions.

  16. Mars Water Today Water flow gullies in crater rim. Slumping material at bottom. N.B. Fig. 8.22 in book is different. It shows recent changes which resemble water flow in last 4-5 years. Mars Global Surveyor image.

  17. Mars Water Today View from Mars Express which resemble frozen ice rafts covered with soil. Similar patterns are seen on Earth in the Antarctic and on Europa.

  18. Climate History • Mars was most likely warmer and wetter in past. • Today, thin atmosphere, weak greenhouse. • 95% CO2 • In past, a thicker atmosphere would support a stronger greenhouse effect. • 400 X as dense atmosphere; • Would give surface Pressure about 3 times that of Earth today; • Temperature above freezing • Ocean hundreds of meters deep.

  19. Why did Mars Change? • Probably lost significant amount of CO2. • Core cooled and solidified • Loss of magnetic field • Solar wind stripping of atmosphere • UV breakdown of water • As cooled, oxygen would also leave or “rust” rocks • Inverse greenhouse effect.

  20. Is Mars Habitable? • Liquid water is the key. • Probably was 2-3 Gyr ago, but for how long? • Not habitable at the current time. • Terraforming

More Related