Venus

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Venus

• By Angela Jekal
• Friday, December 5th

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Venus Earths Sister Planet

• Venus and Earth are both terrestrial planets
• Venus is only slightly smaller than Earth (95 of
  Earth's diameter, 80 of Earth's mass
• Venus surface gravity and average density is
  close to Earths
• Both have craters that indicate young surfaces
• Both have similar chemical compositions
• This leads to the following question If Venus is
  so similar to Earth, can it support life?

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Differences between Venus and Earth

• Closer to the Sun
• Much more heated
• Virtually waterless
• Thick, dense atmosphere
• Thick cloud layer of sulfuric components
• Makes Venus very difficult to learn about
• All these characteristics prove that Venus
  cannot support life

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Brightness

• At brightest, Venus is 16 times brighter than
  the brightest star, only outshone by the moon and
  the sun
• Oftentimes it is called the evening star or the
  morning star
• Reasons
• - big size (about Earth-size)
• - proximity to the Sun
• - proximity to the Earth
• - reflects 59 of the sunlight that falls on
  the planet

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Motion

• Venus rotates very slowly one sidereal
• period takes 243 days, which is longer
• than its orbital period around the sun
• It is believed that Venus lacks a
• magnetic field because of its slow prograde
  rotation
• rotation
• Venus spins on its axis in retrograde
• rotation, where the planet rotates in
• the opposite direction in which it orbits
• the sun
• retrograde rotation

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The Terrain

• Volcanism leads scientists to believe
• that Venus has a molten interior
• Venus has the most volcanoes of all the
• planets in the solar system over 1600
• volcanoes are mapped, but there may be
• about 100,000 to a million volcanoes
• pancake volcanoes

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• Not much elevation contrast
• Highlands
• Ishtar Terra
• Highest point on Venus Maxwell Montes
• Aphrodite Terra
• Biggest land feature on Venus
• Wraps around 16,000 km around equator
• 2,000 km wide
• Craters
• There are about a thousand craters,
• which tells us Venuss surface is relatively
  young

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The atmosphere and the Greenhouse Effect

• The atmospheric pressure is 90 times that of
  Earth
• Venus has a thick cloudy layer of sulfur
  components from volcanic activity
• The atmosphere is 96.5 CO2, a major greenhouse
  gas
• Venus suffered from Runaway Greenhouse Effect

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Exploring Venus

• Mariner 2
• First close flyby in 1962
• Measured radiation with microwaves of wavelengths
  1.35 cm and 1.9 cm
• Venera 7
• Transmitted data by 1970 by the Soviet Union
• First to descend into the atmosphere
• Discovered the exact 460ºC (860ºF) surface
  temperature
• Discovered the atmospheric pressure to be 90
  times the atmospheric pressure on Earth
• Magellan
• Went into orbit in 1990
• Mapped out 98 of the planet and over 1600
  volcanoes
• Provides our most detailed images thusfar

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Venus is Interesting!

• Almost all terrain features of Venus are named
  after female figures in history or legend
• Galileo disproved the Ptolemaic system by
  observing the moonlike phases of Venus
• Solar transit will happen on June 8, 2004 and
  June 6, 2012 the last two times this happened
  was in 1874 and 1882

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Bibliography

• Freedman, R. Kaufman, W. (2002). Universe.
  New York W.H. Freeman and Company.
• http//imagine.gsfc.nasa.gov/docs/ask_astro/answer
  s/981026a.html
• http//www.nasm.si.edu/ceps/etp/venus/
• http//www.reachoutmichigan.org/funexperiments/age
  subject/lessons/images/diagrampage.html
• http//seds.lpl.arizona.edu/nineplanets/nineplanet
  s/pxvenus.html
• http//spacelink.msfc.nasa.gov/Instructional.Mater
  ials/Curriculum.Support/Space.Science/Our.Solar.Sy
  stem/Venus/
• http//www.spaceweather.com/planets/gallery_07may0
  3.html
• http//volcano.und.nodak.edu/vwdocs/planet_volcano
  /venus/intro.html