charles hakes fort lewis college1 photos. charles hakes fort lewis college2 chapter 4, 5 debris -...

Charles HakesFort Lewis College 1

Photos


Chapter 4, 5

Debris -

Asteroids and Comets


Tutor (Shane)

Thursday 5-6 (or longer if needed) BH640


Movie comments

Martian atmosphere Asteroid density


Debris

• Asteroids• Mostly between Mars and Jupiter.• Silicate (rocky) predominate inner region• Carbonaceous more common as you move out

• Meteoroids - Little Asteroids• Micrometeoroids -

• Really little ones (dust)• Often follow comet paths

• Comets - Dirty Snowballs


Chapter 4Asteroid Eros


Asteroids (Minor Planets)

• Most are in the “Asteroid belt” between Mars (1.5 AU) and Jupiter (5.2 AU).

• Largest is Ceres (940 km in diameter).• Orbits generally more elliptical than planets• Trojan asteroids - in stable orbits 60°

ahead of and behind Jupiter.• Vesta - http://apod.nasa.gov/apod/ap110919.html

http://apod.nasa.gov/apod/ap110919.html


Figure 4.4Inner Solar System


Figure 4.6Asteroid Images


Figure 4.7Asteroid Eros


Asteroid Density

• How close are the Asteroids to each other?


Asteroid Density

• How close are the Asteroids to each other?• Number of known asteroids ~100,000.• Distance from sun 2-4 A.U.


Asteroid Density

• How close are the Asteroids to each other?• Number of known asteroids ~100,000.• Distance from sun 2-4 A.U.• Area ~ (4AU)2 - (2AU)2 = 8.5x1017 km2

• Say there are really lots more… (~1,000,000,000)

• Then each one still gets 8.5x108 km2


Asteroid Density

• How close are the Asteroids to each other?• Number of known asteroids ~100,000.• Distance from sun 2-4 A.U.• Area ~ (4AU)2 - (2AU)2 = 8.5x1017 km2

• Say there are really lots more… (~1,000,000,000)

• Then each one still gets 8.5x108 km2 Distance = 3x104 km (~2.5x diameter of Earth)


Asteroids (Minor Planets)

• Over 2000 Earth-crossing asteroids are known.

• Near Earth - http://apod.nasa.gov/apod/ap111001.html

http://apod.nasa.gov/apod/ap111001.html


Discovery 4-1aWhat Killed the Dinosaurs?


Figure 4.15Barringer Crater (near Winslow, AZ ~25,000 years ago)


Figure 4.17Tunguska Debris (Siberia, 1908)


Figure 4.16Manicouagan Reservoir (~200,000,000 years ago)


Discovery 4-1bWhat Killed the Dinosaurs?


Figure 4.18Meteorite Samples a) stony silicate b) iron


This is:

A) A natural rock outcropping

B) New FLC Landscaping

C) Something else


Comets

• Dirty snowballs


Comets

• Nucleus • Dirty Snowballs - “dirt” accumulates on surface• Often only a few km in diameter

• Coma• Bright part around the nucleus• Could be 100,000 km in diameter

• Tail• Could be up to 1 A.U. in length!• Ion Tail - points directly away from the Sun• Dust Tail - points away from Sun, but “drags” a bit.

• Hydrogen Envelope - surrounds all, but not visible


Figure 4.8Halley’s Comet


Figure 4.9Comet Tails a) Giacobini-Zinner b) Hale-Bopp (1997)


Figure 4.10Comet Trajectory


Figure 4.11Halley’s Comet Closeup from Giotto spacecraft


Figure 4.12Comet Reservoirs

•Oort Cloud •huge•spherical•reservoir of long period comets

•Kuiper Belt•outside the orbit of Neptune•in plane of solar system•reservoir of short period comets•e.g. Haley’s comet


Figure 4.14Meteor Showers


Figure 4.13Meteor Trails


Three Minute Paper

• Write 1-3 sentences.• What was the most important thing

you learned today?• What questions do you still have

about today’s topics?

charles hakes fort lewis college1 photos. charles hakes fort lewis college2 chapter 4, 5 debris -...

Documents

debris asteroids

planetstrojan asteroids

number of known asteroids

asteroid densityhow

asteroids minor planetsmost

asteroids minor planetsover

asteroid belt

5x108 km2 distance