Section 4: Other Objects in the Solar System Chapter 12: The Solar System Section 4: Other Objects in the Solar System

A. Comet – dust and rock particles combined with frozen water, methane, and ammonia 1. Halley’s comet orbits the Sun every 76 years

2. Oort Cloud - large group of comets surrounding solar system beyond Pluto

3. Amateur astronomers discovered Comet Hale-Bopp in 1995

4. Comet structure – large dirty snowball of frozen rock and ice a. Ice and dust vaporize as comet nears Sun b. Vaporized material forms bright cloud called coma around comet nucleus

c. Solar wind pushes on gas and dust in the coma, causing the particles to form a tail that always points away from the Sun d. Eventually, most of the ice in the comet’s nucleus vaporizes, leaving only small particles

B. Small pieces of the old comet’s nucleus 1. Meteoroid – name given to small pieces of comet when they move through space

2. Meteor – small meteoroid that burns up in Earth’s atmosphere

3. Meteor showers – occur when Earth’s orbit passes through a group of meteoroids that enter the atmosphere

4. Meteorite - meteoroid that strikes Earth

C. Asteroid – rock similar to that which formed planets 1. Most asteroids lie in an asteroid belt located between Mars and Jupiter

2. Jupiter’s gravity may have kept these asteroids from forming a planet 3. Some planets’ moons may be asteroids pulled from the asteroid belt Phobos (a Mars moon)

4. Asteroid sizes range from tiny to 940 km in diameter

5. The Near Earth Asteroid Rendezvous probe indicates asteroid 433 Eros has been in many collisions over time

Patterns of Stars Constellations are groups of stars that form a “picture” (Ex: Ursa Major, also called Great Bear)

Constellations appear in different parts of the sky at different times of the year.

Aquarius – January 20th to February 18th

Traditional Aquarius Personality Traits Positive Traits Friendly and humanitarian Honest and loyal Original and inventive Independent and intellectual Negative Traits Intractable and contrary Perverse and unpredictable Unemotional and detached

Pisces – February 19th to March 20th

Traditional Pisces Personality Traits Positive Traits Imaginative and sensitive Compassionate and kind Selfless and unworldly Intuitive and sympathetic Negative Traits Escapist and idealistic Secretive and vague Weak-willed and easily led

Aries – March 21st to April 19th

Traditional Aries Personality Traits Positive Traits Adventurous and energetic Pioneering and courageous Enthusiastic and confident Dynamic and quick-witted Negative Traits Selfish and quick-tempered Impulsive and impatient Foolhardy and daredevil

Taurus – April 20th to May 20th

Traditional Taurus Personality Traits Positive Traits Patient and reliable Warmhearted and loving Persistent and determined Placid and security loving Negative Traits Jealous and possessive Resentful and inflexible Self-indulgent and greedy

Gemini – May 21st to June 20th

Traditional Gemini Personality Traits Positive Traits Adaptable and versatile Communicative and witty Intellectual and eloquent Youthful and lively Negative Traits Nervous and tense Superficial and inconsistent Cunning and inquisitive

Cancer – June 21st to July 22nd

Traditional Cancer Personality Traits Positive Traits Emotional and loving Intuitive and imaginative Shrewd and cautious Protective and sympathetic Negative Traits Changeable and moody Overemotional and touchy Clinging and unable to let go

Leo – July 23rd to August 22nd

Traditional Leo Personality Traits Positive Traits Generous and warmhearted Creative and enthusiastic Broad-minded and expansive Faithful and loving Negative Traits Pompous and patronizing Bossy and interfering Dogmatic and intolerant

Virgo – August 23rd to September 22nd

Traditional Virgo Personality Traits Positive Traits Modest and shy Meticulous and reliable Practical and diligent Intelligent and analytical Negative Traits Fussy and a worrier Overcritical and harsh Perfectionist and conservative

Libra – September 23rd to October 22nd

Traditional Libra Personality Traits Positive Traits Diplomaitic and urbane Romantic and charming Easygoing and sociable Idealistic and peaceable Negative Traits Indecisive and changeable Gullible and easily infuenced Flirtatious and self-indulgent

Scorpio – October 23rd to November 21st

Traditional Scorpio Personality Traits Positive Traits Determined and forceful Emotional and intuitive Powerful and passionate Exciting and magnetic Negative Traits Jealous and resentful Compulsive and obsessive Secretive and obstinate

Sagittarius – November 22nd to December 21st

Traditional Sagittarius Personality Traits Positive Traits Optimistic and freedom-loving Jovial and good-humored Honest and straightforward Intellectual and philosophical Negative Traits Blindly optimistic and careless Irresponsible and superficial Tactless and restless

Capricorn – December 22nd to January 19th

Traditional Capricorn Personality Traits Positive Traits Practical and prudent Ambitious and disciplined Patient and careful Humorous and reserved Negative Traits Pessimistic and fatalistic Miserly and grudging