Goal: To compare Neptune to its neighbor Uranus

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Goal To compare Neptune to its neighbor Uranus

• Objectives
• To learn about its Atmosphere
• To explore its Core
• To learn about its Moons
• If time left How the formation of the solar
  system affected the orbits of the gas giants.

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Voyager 2
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Springtime on Neptune
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Neptune in 3 D
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Atmospheric make up

• Molecular hydrogen (H2) - 80.0 (3.2)
• Helium (He) - 19.0 (3.2)
• Methane (CH4) 1.5 (0.5) (Uranus was 2.3)
• Hydrogen Deuteride (HD) 192
• Ethane (C2H6) - 1.5
• Aerosols Ammonia ice, water ice, ammonia
  hydrosulfide, methane ice(?)

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Neptune winds

• With little turbulence to dampen winds, the winds
  on the equator get as high as 1200 miles per
  hour.
• Neptune also emits twice as much energy in the
  infrared that the energy in the optical it gets
  from the sun.
• So, that means Neptune rains diamonds towards the
  core to generate heat!

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Core
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Rings
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Moons

• Neptune has 13 known moons. Very few have images
  which are any good.
• Only one is large, Triton. Two are about 400 km
  in diameter. Rest are much smaller.

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Proteus
Very dark (reflects about 7 of
sunlight). 120,000 km from Neptune Outer most
of Neptunes probable original moons. 5 moons
inside of Proteuss orbit. Nearest to Neptune is
Naiad which is at 48k km from Neptune (29 km in
diameter).
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Triton
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interesting
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Triton up close!

• http//www.space.com/common/media/video/player.php
  ?videoRefSP_090902_triton

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Triton is a captured TNO!

• TNO Trans-Neptunian Object (an object like
  Pluto).
• Diameter 2700 km, which is a little smaller than
  our moon.
• About 10 closer to Neptune than our moon is from
  us.
• Its orbit is retrograde! This is a backwards
  orbit, which can only be if it was captured.
• However, this has some other implications

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Tritons impact on Neptune

• Retrograde orbit means that tidal interactions
  with Neptune bring it CLOSER to Neptune!
• This means it was once further out, and probably
  tossed all of Neptunes original moons which
  started further out that its current position
  away from Neptune.
• Eventually it will do the same to all the inner
  moons.
• Is probably the reason the outer moons have some
  very high eccentricities.

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The death of Triton

• In a billion years (maybe less) Triton will get
  close enough to Neptune for Neptune to rip it
  apart.
• This will create a spectacular ring system around
  Neptune even dwarfing the Saturn ring system.
• Until then, we still get to see fireworks as the
  volcanism on Triton caused by the Tides of
  Neptune continue to increase.

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Conclusion

• Neptune is similar to Uranus in many ways, the
  real difference being the moons because of the
  chaos the captured moon Triton has caused on the
  Neptune moon system.