1 / 20

Pic/Puzzle of the Day & Announcements for Nov 3, 2008

Pic/Puzzle of the Day & Announcements for Nov 3, 2008. Quiz #4: Wednesday. HW4 solns: Posted later today. Other: Office hours today, until 3 (other by appt) Guest Lecture on Mars! (Wednesday/Monday). Today:. 1. Geology of Mercury & Venus 2. Venusian Atmosphere

plato
Télécharger la présentation

Pic/Puzzle of the Day & Announcements for Nov 3, 2008

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. Pic/Puzzle of the Day & Announcements for Nov 3, 2008 Quiz #4: Wednesday HW4 solns: Posted later today • Other: Office hours today, until 3 • (other by appt) • Guest Lecture on Mars! (Wednesday/Monday)

  2. Today: 1. Geology of Mercury & Venus 2. Venusian Atmosphere 3. Earth vs. Venus - This planet is TOO HOT

  3. Mercury - An “Extreme” Planet • Closest Planetto the Sun • 0.38 AU, 2.5 x closer than Earth • sunlight is 6.25 x more intense! • Highest Density other than Earth • Largest Temperature Swings • more than 1000 F! • Interesting Rotation • Global Magnetic Field

  4. Mercury in the Sky • Closest Planetto the Sun • Hard to observe What time of day is Mercury observable?

  5. Mercury - Early Observations • Closest Planetto the Sun • Hard to observe (imagination required!) Giovanni Schiaparelli (1835-1910) • Mercury Rotates Slowly • Synchronous? • T?

  6. Mercury - Synchronous Rotation? 1962 - Radiation from Mercury not so cold X Not Synchronous 1965 - Dyce & Pettengill DOPPLER EFFECT How??

  7. Mercury - Synchronous Rotation? 1962 - Radiation from Mercury not so cold X Not Synchronous 1965 - Dyce & Pettengill Rotation Period = 59 Days (Orbital Period = 88 Days)

  8. Earth rotates on its axis ~365 times for each revolution around the Sun Mercury rotates on its axis exactly 1.5 times for each revolution around the Sun (3:2 spin-orbit resonance) How long is a day on Mercury? Rotation Period = 59 Days (Orbital Period = 88 Days) 1 day on Mercury = 176 Earth days Longer than 1 year!

  9. ? Mercury & Einstein Observation: Mercury’s Orbit Precesses General Relativity! Space is curved by Sun’s mass! WHY??

  10. Mercury - Overview Planet of Extremes

  11. Large iron core Small Magnetic Field (1% Earth) Mercury - Spacecraft data Mariner 10: Venus/Mercury flyby (1974) Flew by 3x before it ran out of fuel! Imaged 45% of surface Calculated HIGH density (4.4g/cm3)

  12. Mercury’s Magnetic Field - Why? Small Magnetic Field (1% Earth) 2007 - Mercury has a small molten core!

  13. Mercury - Spacecraft data Messenger - Recent close approach Feb. 1 & Oct. 6, 2008! Mercury orbit - March 18, 2011

  14. Messenger Terrain South Pole

  15. Messenger Terrain - Similar to Moon!

  16. Mercury - Surface Features Heavily Cratered Areas - Old (Heavy Bombardment) Large smooth Basins - Younger, Lava from Large impacts?

  17. Mercury - Surface Features Messenger Images

  18. Mercury - Surface Features Caloris Basin - largest feature on Mercury -size of Texas -jumbled terrain opposite -caused by large impact

  19. Mercury - Surface Features Scarps: Large cliffs caused by contraction of surface -3 km high -100s of km across -contraction from cooling (planet shrank by ~20km!) -closed off volcanic vents

  20. Mercury - Unsolved Mysteries - “Mysterious dark blue material??” -Ice on Poles? -size of molten core?

More Related