WHAT IS A STAR & HOW MANY

DIFFERENT KINDS ARE THERE?

By: ADRIAN SEAN D. APARILLA Aaron Kyle R. Daug Environmental science Grade 6 - Neil Armstrong

OutlineSean : • All About stars• Classifications• History• Descriptions• Life Cycle

Aaron : • Types of Stars• Definitions for every Star

ALL ABOUT STARS

CLASSIFICATIONS

Star Type

Color Approximate

Surface Temperature

Average Mass (The Sun = 1)

Average Radius (The

Sun = 1)

Average Luminosity

(The Sun = 1) Main Characteristics Examples

O Blue over 25,000 K 60 15 1,400,000

Singly ionized helium lines (H I) either in emission or

absorption. Strong UV continuum.

10 Lacertra

B Blue 11,000 - 25,000 K 18 7 20,000 Neutral helium lines (H II) in

absorption. Rigel Spica

A Blue 7,500 - 11,000 K 3.2 2.5 80 Hydrogen (H) lines strongest for A0 stars, decreasing for

other A's. Sirius, Vega

F Blue to White

6,000 - 7,500 K 1.7 1.3 6 Ca II absorption. Metallic lines become noticeable.

Canopus, Procyon

G White to Yellow

5,000 - 6,000 K 1.1 1.1 1.2 Absorption lines of neutral

metallic atoms and ions (e.g. once-ionized calcium).

Sun, Capella

K Orange to Red

3,500 - 5,000 K 0.8 0.9 0.4 Metallic lines, some blue

continuum. Arcturus, Aldebaran

M Red under 3,500 K 0.3 0.4 0.04

(very faint) Some molecular bands of

titanium oxide. Betelgeuse,Antares

An easy mnemonic for remembering these is:

• O - oh• B - be• A - a• F - fine• G - girl• K - kiss• M - me

HISTORY

Ancient people: quadrant

1584 : Giordana Bruno

Greek astronomers: Ptolemy and Hipparchus20th century

DESCRIPTIONS OF STARS

• a luminous globe of gas• nebulae & consist of hydrogen and

helium gas• 2000°C to above 30,000°C• brightest stars - 100 times that of the

Sun• smallest mass for a star is about 8%

that of the Sun

DIFFERENT KINDS OF STAR

The different kinds of stars are:

• Yellow dwarf stars• Orange dwarf stars• Red dwarf stars• Brown dwarfs• Blue giant stars• Red giant stars• Red super giant stars• White dwarfs• Black dwarfs• Neutron stars

Yellow Dwarf Stars (the sun, Alpha Centauri A, Kepler-22)

• Lifetime: 4 - 17 billion years• Evolution: early, middle• Temperature: 5,000 - 7,300 °C• Spectral Types: G, F• Luminosity: 0.6 - 5.0• Radius: 0.96 - 1.4• Mass: 0.8 - 1.4• Prevalence: 10%

Brown Dwarfs

• Lifetime: unknown (long)• Evolution: not evolving• Temperature: 0 - 1,800 °C• Spectral Types: L, T, Y (after M)• Luminosity: ~0.00001• Radius: 0.06 - 0.12• Mass: 0.01 - 0.08• Prevalence: unknown (many)

Orange Dwarf Stars(Alpha Centauri B and Epsilon Eridani)

• Lifetime: 17 - 73 billion years• Evolution: early, middle• Temperature: 3,500 - 5,000 °C• Spectral Types: K• Luminosity: 0.08 - 0.6• Radius: 0.7 - 0.96• Mass: 0.45 - 0.8• Prevalence: 11%

Red Dwarf Stars(Proxima Centauri, Barnard's Star and Gliese 581)• Lifetime: 73 - 5500 billion years• Evolution: early, middle• Temperature: 1,800 - 3,500 °C• Spectral Types: M• Luminosity: 0.0001 - 0.08• Radius: 0.12 - 0.7• Mass: 0.08 - 0.45• Prevalence: 73%

Red Supergiant Stars (Betelgeuse and Antares)

• Lifetime: 3 - 100 million years• Evolution: late• Temperature: 3,000 - 5,000 ºC• Spectral Types: K, M• Luminosity: 1,000 - 800,000• Radius: 100 - 1650• Mass: 10 - 40• Prevalence: 0.0001%

Blue Giant Stars(Rigel)

• Lifetime: 3 - 4,000 million years• Evolution: early, middle• Temperature: 7,300 - 200,000 °C• Spectral Types: O, B, A• Luminosity: 5.0 - 9,000,000• Radius: 1.4 - 250• Mass: 1.4 - 265• Prevalence: 0.7%

hubpages.com

Red Giant Stars(Aldebaran and Arcturus)

• Lifetime: 0.1 - 2 billion years• Evolution: late• Temperature: 3,000 - 5,000 °C• Spectral Types: M, K• Luminosity: 100 - 1000• Radius: 20 - 100• Mass: 0.3 - 10• Prevalence: 0.4%

White Dwarfs(Sirius B and Van Maanen's star)

• Lifetime: 1015- 1025 years• Evolution: dead, cooling• Temperature: 4,000 - 150,000

ºC• Spectral Types: D (degenerate)• Luminosity: 0.0001 - 100• Radius: 0.008 - 0.2• Mass: 0.1 - 1.4• Prevalence: 4%hubpages.com

Black Dwarfs

• Lifetime: unknown (long)• Evolution: dead• Temperature: < -270 °C• Spectral Types: none• Luminosity: infinitesimal• Radius: 0.008 - 0.2• Mass: 0.1 - 1.4• Prevalence: ~0%

Neutron Stars

• Lifetime: unknown (long)

• Evolution: dead, cooling

• Temperature: < 2,000,000 ºC

• Spectral Types: D (degenerate)

• Luminosity: ~0.000001

• Radius: 5 - 15 km• Mass: 1.4 - 3.2• Prevalence: 0.7%

References & Sources:

> kidsastronomy.com> Wikipedia, the free encyclopedia> en.wikipedia.org> www.space.com> www.universetoday.com> hubpages.com> http://www.universetoday.com/25156/history-of-stars/#ixzz38l9lLV4U> http://planetquest.jpl.nasa.gov/science/science_index.cfm> http://cosmology.carnegiescience.edu/timeline/1838>www.google.com.ph/search?q=LIFE+CYCLES+of+stars+ASTRONOMY&tbm=isch&ei=tTLWU8fhKIL48QWapIFA#facrc=_&imgdii=Uqcwn9o5Dk63TM%3A%3B5i7DEMwbIdTJ8M%3>www.google.com.ph/search?q=description+of+stars+ASTRONOMY&source=lnms&sa=X&ei=icbWU9LqI4yl8AWcgoHQCA&ved=0CAUQ_AUoAA&biw=1280&bih=699&dpr=1

THANK YOU