The Solar System:

A Family Portrait

Q.How did the solar system form?A. (possible) The Nebular Theory

1. Nebular Cloud2. This massive loosely-bound cloud of dust, ice particles, and gases

(primarily hydrogen and helium) had some small rate of rotation due to the method in which it was formed.

3. Over time, this nebular cloud began to collapse inward. The collapse may have itself been triggered by a supernova that sent shockwaves through the cloud causing it to compress.

4. As the cloud compressed on itself, the gravitational attraction of the matter within increased and pulled the material in even further.

5. The nebula continued to contract under the influence of gravity causing it to spin faster. The more the cloud contracted, the faster it rotated due to the conservation of angular momentum.

6. The rate of contraction was greatest near the center of the cloud where a dense central core began to form.

7. As the rate of rotation of the nebula continued to increase, centrifugal effects caused the spinning cloud to flatten into a disk with a bulge at its center.

Q.How did the solar system form?A. (possible) The

Condensation with Accretion Model

http://physics.uoregon.edu/~jimbrau/astr121-2005/Notes/Chapter15.html

Nebular Theory, Illustrated

Sun

Basic Motion Vocabulary

http://www.youtube.com/watch?v=lkWyM-M8o0c

The Zodiac: Nothing to live by, but something to dance to!

Definition: The set of constellations that the sun, moons, and major planets move across.

Due to the fact that the planets revolve around the Sun’s center of gravity, the 8 major planets form a fairly flat disk, which from Earth is seen as a linear path in the sky, called the ecliptic. The background constellations for the ecliptic form the zodiac.

Members of the Kuiper Belt and Oort Cloud are less restricted to the ecliptic, due to the sun’s weaker gravity at that distance. So comets can be seen in almost any constellation.

Ecliptic and Equator

How the Dance Works…

http://www.astronomynotes.com/nakedeye/s5.htm

Zodiac, cont.

The sun takes about a month to pass through each zodiacal constellation.

Since the sun and moon both occupy about the same area in our sky (~ one degree, or one fingertip), eclipses can occur when the two are in the same constellation – hence the term, ecliptic.

Basic Overview of the Solar System

• http://www.space.com/12288-solar-system-photo-tour-sun-planets-moons.html

Mercury

• Smallest major planet• rotates three times in

two of its years. • Very little atmosphere;

looks very much like moon.

• Inferior orbit to earth; goes through phases.

The Phases of Mercury

http://www.aaa.org/month0901

Venus Earth’s “twin” due to

being close in size.Retrograde rotation. Extremely thick

atmosphere of CO2 and H2SO4 makes for “Greenhouse Effect” run amock.

Venus is hottest and most volcanic planet in Solar System.

♀

Phases of Venus

http://apod.nasa.gov/apod/ap060110.html

Earth

Only place in universe known to have…

Water in liquid form Large amounts of O2

Life

MarsTantalizing with its bright red

color due to iron oxide surface, polar ice caps, and evidence of water having once flowed on its surface. A Martian day is almost the same as an Earth day.

Largest volcano in Solar System – Olympus Mons (or Tharsis Rise?)

Largest Canyon – Valles Marineris

Through the telescope – what you’ll see

Martian Moons – Phobos & Deimos

Jupiter Largest planetMostly composed of H2

Colorful bands actually mark global wind belts.

“ Great Red Spot” – huge storm that continues to blow around the southern hemisphere for eternity(?)

Has four major (“Galilean”)moons – Io, Europa,

Ganymede, Callisto – plus

many, many more

From Earth – what you’ll see

Io

Innermost of Jupiter’s moons

First extraterrestrial object discovered to have active volcanoes; Extremely tectonically active due to tidal forces exerted by Jupiter

More on Io

Io is the most volcanically active body in the solar system.

http://www.astro.washington.edu/courses/labs/clearinghouse/labs/Io/volcanoes_io.html

Europa – an icy world

Thought to be covered with water ice, which occasionally erupts out in geyser form

What’s in those cracks?

Callisto & Ganymede

Callisto has pockmarked surface due to comet impacts

Ganymede

Largest moon in Solar System

Asteroids

Fire from the heavens

• http://neo.jpl.nasa.gov/images/ida.html

Saturn

Most beautiful telescope object in solar system

Planet is naked-eye; rings are not.

Rings composed of ice and rock

Saturn through the telescope

Titan – Saturn’s unusual moonYou “will find a tropical world

where temperatures plunge to minus 274 degrees Fahrenheit, methane rains from the sky and dunes of ice or tar cover the planet's most arid regions.”

http://www.sciencedaily.com/releases/2007/10/071002114345.htm

Uranus Blue due to CH4 in its upper

atmosphere. Completely bizarre axis tilt – why? this planet is so tilted that it's poles

are alternately facing the Sun. This means that while one pole is getting 42 years of continuous sunlight, the opposite pole gets 42 years of darkness. This would lead one to believe that the polar region facing the Sun would be the hottest point on the planet, but it isn't, the equator is hotter than any of the poles during their days in the Sun.

Uranus through the telescope

Uranian MoonsNamed after

Shakespearian characters.

The Broken Moon - Miranda

Was it shattered by a comet impact – then came back together?

Neptune

Last of the major planets.

Neptune through the telescope

Largest of Neptune’s moons – Triton

Contains ice volcanoes? Retrograde orbit is bringing it ever closer to

Neptune.

Beyond the Planets:

Kuiper Belt v. Oort Cloud

Kuiper Belt

http://www.solstation.com/stars/kuiper.htm

Oort Cloud

http://www.solstation.com/stars/oort.htm

Comets and Meteors – related?

Comets – Kuiper & Oort objects that somehow get bumped out of their orbit and so begin making trips into the inner solar system, sublimating as they near the sun, thus forming beautiful tails. This tail material refreezes and remains suspended in space.

Meteors – As Earth passes through these comet remains, our atmosphere catches them up like a vacuum cleaner and they disintegrate as a streak of light.

Current Positions for Planets

http://www.fourmilab.ch/cgi-bin/Solar/action?sys=-Sf

How old will you be when each of these planets RETURNS to its current place?