Solar DebrisAsteroids, Meteors and Comets

Asteroids-Locations-Types-Meteors-Impacts

What is an asteroid? A small solar system object in orbit

around the sun composed mostly of rock

Sometimes called “Minor Planets”

Location of Asteroids Near Earth Asteroids:

› Asteroids that orbit within the earth’s orbit› NEA

NEA asteroids Mathilde 1950 DA

› May hit earth in 2880

Location of Asteroids Main Belt Asteroids:

› Asteroids that orbit between Mars and Jupiter

› AKA Asteroid Belt› Have stable orbits› Largest Asteroid - Ceres

Location of Asteroids Trojans:

› Asteroids that are trapped in Jupiter’s orbit due to it’s strong gravitational pull

› Lagrange points 60 degrees in front/behind Jupiter

Location of Asteroids Most asteroids

located in the asteroid belt

Types of asteroids C-type S-Type M-type

C-type Composition-

Carbonaceous (lots of carbon)

Color-Very dark Percent- Most common

type of asteroid (75%) Primitive

› Unchanged since formation

› Can be used to study early solar system

S-type Composition-Silicate

(SiO2) Color-Light in color

› easier to see Percent-Make up

15% of asteroids Some primitive some

differentiated› Geologic activity has

changed some of the rocks

M-Type Composition - Metallic Origin-Metal cores of

larger asteriods that broke apart

Color-Bright and reflective

Percent-Rare (5-10%) Differentiated

› Have melted since they formed.

Solar Debris Day 2Meteorites and Impacts

Meteor vs. Meteorites Meteorites:

› Small pieces of › asteroids that› hits the earth's › atmosphere

Terminology Meteoroid is a small object traveling through

space...it could have once been part of an asteroid 'Shooting Star' occurs when a meteoroid enters the

atmosphere. . Meteor Showers occur when the dust particles

from an aged comet pass through the Earth's atmosphere

Meteor is the bright fireball seen when a sizeable meteoroid enters the Earth's atmosphere and begins to burn...

Meteorite is the resulting body that has traveled through the atmosphere, survived the entry, and has landed on Earth

Meteorites 37,000 – 78,000 tons of material fall to

the earth each year Most are dust sized particles Shooting stars occur when meteriods

enter the atmosphere and start ot burn up

Types of Meteorites Stony Iron Stony-Iron

Stony Composition –

Silicate Rock Most common type Hardest to find

because it looks like rock

Primitive Contain Chondrules

Chondrule Small organic

particles left over from the formation of the solar system

Iron Composition – Metal

(iron and nickel) Not common type Easy to find iron

meteorites because unoxidized iron does not form on earth

DifferentiatedPieces of M-Type

asteroids

Stoney-Irons Composition – Mix

of Silicate and Metal Very Rare Easier to find then

stoneys because of the iron

Location Deserts

› Metal detectors easily detect iron› Very little erosion to destroy meteorites

Location Antartica

› Metal detectors easily detect iron› Very little erosion to destroy meteorites› Meteorites contrast with snow› Moving glaciers push meteorites into piles

Exit Slip Contrast s, m and c type asteriods Compare and Contrast stoney, iron,

iron-stoney meteorites Tell me what a meteor shower is

Warm-up What are the three types of Asteriods? What are the three types of

Meteorites?

Terrestial Impacts a. Asteroids have hit the Earth in the

past and WILL hit the earth in the future

Earth Impacts

Impact Craters Barringer Crater

› (1.2 km Diameter)

Manicouagan Impact Crater › (70 km in

Diameter(

Impact Craters Vredefort Crater

› (140 km Diameter)

Richat Crater › (38 km in

Diameter(

Known Impact Craters

Chiczulub Crater

Moon Impacts

Crater Chain Tycho Crater

Mars Impact

Crater Structure

Crater Ejecta Blanket –

› a layer of debris surrounding an impact layer

Breccia – › crushed rock underneath the impact site

Tektites: › small glassy rocks that were melted during

impact and blown through the air› Found in the Ejecta blanket

Tektites

Shocked Quartz Minerals that get compressed due to

impact Found below the craters

Comets

What is a comet? Small solar system body that orbits the

sun Collections of ice, dust and rocky

particles Different from asteroids because of the

tail

Comet’s Tail Exhibits a visible

coma and tail when it gets close enough to the sun

The tail is a result of solar radiation

Coma/Tail Coma

› Streams of dust and gas released from the atmosphere around the comet

Tail› Streams of dust

and gas that point in slightly different directions

› Dust reflects sun

Locations of Comets

Oort Cloud Large Spherical cloud of billions of

comets Surrounds the solar system 50000 to 100000 AU

Kuiper Belt Kuiper Belt

› A belt of millions of comets from 30 to 100 AU from the sun

› From the orbit of neptune outward› Discovered in 1992

Kuiper Belt Orbit

Kuiper Belt Objects Quaoar

› Distance: 43 AU› Diameter: 800

miles

Quaoar’s Orbit

Kuiper Belt Objects Sedna

› Distance: 86 AU› Diameter: 1000

miles› Probably has a

moon

Kuiper Belt Objects Pluto

› Distance: 39.5 AU› Diameter: 1470 miles› Has moon: Charon

PlutoSimilar size and same composition as

other KBO’s

Large Kuiper Belt Objects:Eris “Xena” 2400 kmPluto 2320 kmSedna ~1800 km136472 1800 km136108 1600 kmQuaoar 1300 km

Meteor Showers Comets leave a trail of debris behind

them that may be meteor showers

Comets

Major annual meteor showers:Shower name Date Comet Comet

Period

Quadrantid Jan 3 ? ?Lyrid April 21 Thatcher 415 yrsEta aquarid May 4 Halley 76 yrsPerseid Aug 11 Swift-Tuttle 105 yrsOrionid Oct 31 Encke 3 yrsLeonid Nov 16 Temple-Tuttle 33 yrsGeminid Dec 13 Phaethon 1.4

Zodiacal Light Comet dust scattered through our solar

system that can be seen directly under a dark/clear sky

Can be seen in the east a few hour before sunrise

Importance of studying CometsSince Comets originate at the edges of our solar system, the Sun’s heat and radiation have not affected comets since their formation.

Because of this, comets still contain volatile elements from the solar system formation that have been baked out of other objects, such as

asteroids and planets.

Therefore, comets are important to study. Their volatile elements give us unique information from the formation of our solar system.

Comet Impacts