Red DwarfRed Dwarf

• Cool, Faint and small stars • 1/10 the mass and diameter of the sun

• Estimated lifetimes of 100 billion years or more • Burn very slowly

• Surface temperature of less than 3500K • Generated through nuclear fusion of hydrogen into helium • When Population III Stars burn out, they leave elements that

allow Red Dwarfs to form • Give off very little light

• Red in color • Not visible to the naked eye

• Examples: Proxima Centauri and Barnard’s Star

Jenna Napolitano

Neutron Star

! Results from the gravitational collapse of a massive star

during a supernova

! Composed entirely of neutrons

! Mass between 1.35 and 2.1 solar masses

! Temp 10^11 to 10^12 Kelvin

! Radius 12km- suns radius 60,000 times that

! 1.5 times mass of sun

! The endpoint of a stars journey

! One teaspoonful on earth would weigh a billion tons

! Discovered in 1932

! Magnetic field 1 million times stronger than earth

Brooke Porter

Supernovae

Remnant of Kepler's Supernova Remnant of Tycho's Nova

Stellar explosion caused by death of a star

Luminous and causes a burst of radiation that outshines a galaxy

In several weeks supernovae can create as much energy as sun in its lifetime

Explosion shoots star’s material up to 30,000 km

This draws a shockwave into the interstellar medium

Triggered by nuclear fusion being turned on or off

Supernovae occur once every 50 years

Occur in galaxies bigger than the Milky Way

Shockwaves from Supernovae explosions form new stars

Shines in the Celestial sphere

Last known supernova in our galaxy occurred around 1680 estimate based on the expansion of its remnant, Cassiopeia A

Astronomers use Very Large Array to see Supernovae’s

Catherine Mason

~Star Clusters~

• Star clusters are groups of stars, there are

two types of star clusters that can be

distinguished;

o Globular Clusters: Tight groups of

millions of very old stars which are

gravitationally bound.

o Open Clusters: Loosely clustered group of

stars, generally contain less then a few

hundred stars, and also much younger.

• Star clusters develop from large clouds of

molecular gas.

• Star clusters form in groups becasuse clouds

are composed of hundreds of solar masses of

material. After remnant gas is heated and blown

away, stars collect together by gravitivity.

• The colors and temperatures of stars in a star

cluster will always vary.

• Star clustures visible to the naked eye include

Pleiades & Hyades.

By: Michael Mullen & Shelby Eagan.

• It is much hotter, bluer, and more

luminous than the Sun.

• It runs on Hydrogen.

• They can reach approximately 40 million

degrees Kelvin.

• It has an Iron core, with layers of Silicon,

Oxygen, Carbon, Helium, and Hydrogen.

• They can be from 10-100 times the size of

the sun.

• They are formed from the shockwaves of

supernovas, causing space debris to

gather.

• They die by losing their fuel source.

Red Giants By Andrea Pelayo

A Red Giant

• End of a star’s existence. Stars change hydrogen to helium to produce

light.

• Hydrogen is depleted. Star collapses, the pressure and temperature

rise. To radiate the energy produced by the helium burning, star

expands into a Red Giant

• Temperature rises which causes the size of the star to expand

• Last phase of a star before they collapse. Our sun will become one in

5 billion years.

• Color is yellow orange to red

• Are tens to hundreds of times larger than our sun

• Primary supply of hydrogen at its core

Black Holes

• A Black Hole is a region of space that is so large and super-

massive that nothing can escape it.

• It forms from a star that collapses onto itself at the end of its cycle.

• There is a very large Black Hole in the center of the Milky Way.

• They are made of nothing and run on nothing.

• They bend space, time and light.

• Karl Schwarzschild is credited with the discovery of Black Holes.

• There is no smallest size for a black hole.

White dwarf

*Second most common kind of stars

*Remains of medium mass stars that fused hydrogen and helium, failed to

ignite carbon, drove away their outer layers to form planetary nebulae, and

collapsed and cooled to form white dwarfs.

*Billions of white dwarfs in our galaxy by the remains of medium mass

stars.

*The first white dwarf discovered was Sirius.

*White dwarf, Sirius B, is 10,000 times fainter then Sirius A.

*White dwarfs mass is about 1 solar mass, and its blue white color tells us

that it’s surface is hot, about 25,000 K. it has a low luminosity so it must

have a small surface area.

* The diameter is only twice the size of earth’s.

*A white dwarf cannot generate energy by nuclear fusion.

*It exhausted its hydrogen and helium fuel and produced carbon.

*White dwarf is supported against its own gravity by the inability of its

degenerate electrons to pack into a smaller volume.

*A white dwarf is not a true star, since it generates no nuclear energy, is

almost totally degenerate and the surface contains no gas.

* As a white dwarf radiates energy into space its temperature gradually falls.

Supergiant

Key Facts

• One of the largest stars

• Masses from 10-70 solar masses

• Vary greatly in Solar Radius

• Short life spans

• Observed in young galactic structures

• Occur in every spectral class

• Several magnitudes brighter and several times larger then

giant stars

• 10 to 1000 times the size of sun

• Example- Betelgeuse in Orion

• Any color, from red to blue on the scale

• The temperature is around 73832 Fahrenheit

• Form in same way as ordinary stars

• Cloud of hydrogen gas and interstellar dust compresses to

fuse hydrogen to form helium.

• Must have mass 6-10 times the sun

• If mass of core is three times the suns, disappears from

universe becoming a black hole.

Sam Simmons

Pulsars

• Are highly magnetized neutron stars that give off a

beam of electromagnetic radiation?

• They are a type of neutron star and are formed by a

nebula exploding in a supernova.

• The pulse that you get flashes from yellow to blue.

• The temperature of a pulsar can be up to 100,000k

• The size of a pulsar is about 20km and it burns nuclear

fuel.

• When a neutron star spins it creates light like a

lighthouse thus creating the look like a pulse.

• If the neutron star dies off and doesn’t spin then we

will not see a pulse

Greg Martin

Hyper-nova/Collapsar

Color and Size

• Does not have any specific color

• Is mostly just dust and decay

• Can seem orange or red

Temperature and Fuel

• Size is much larger than sun

• Explosion would destroy and kill

everything in a 1600ly radius

• Very rare

• Larger than supernovas

• Extremely hot

• Blast could possibly be hotter

than the sun at one point in the

explosion.

How does it form/Characteristics

• A large star collapses into a black

hole.

• Emits twin energetic jets at both

ends.

• Then it’s surrounded by an

accretion disk.

• Produces powerful dangerous

gamma ray blast

• Very rare to happen.

• Is fueled by the decay of 56 Ni

from the explosion of the star.

• Only happens with massive sized

stars

Anatomy

• It has radioactive neon and nickel

in the core of the hyper-nova.

• Consist of extreme heat.

• After, cools down into a dust

cloud.

• White dwarfs are formed and the

cycle starts again.

Matthew Theriault

Entering

The next Phase

• Star

explodes

into

black

hole

• A black

hole is

formed

• Nothing

is left but

the black

hole

Brown Dwarf/ Black Dwarf

• Formed when a forming star does not have enough

mass to begin hydrogen fusion

• Color: Varying deep red to magenta depending on

temperature

• Temperature: 1000K

• Size in relativity to the Sun: mass less than .075 that of

the sun, Less than 8% of the Sun’s mass

• Fuel: Deuterium (Heavy Hydrogen with an extra

neutron) to Helium

• The Next Phase: Brown Dwarf star cools off further

until it becomes a Black Dwarf star

Maya Lee

Binary Stars

• Pairs of stars that orbit each other

• Each star moves in it’s own orbit

• Emerges from a cloud of gaseous material

• They collapse and form more than one star at the same

time

• They form in the same area

• Three distinct binary stars, Visual , Spectroscopic, and

eclipsing

• More than half of all stars are in binary systems

• They are masses of stars

• Held by the force of gravity

• Some pairs are the same brightness

• When their different, one is blue and the other is red

• Fuel: Hydrogen

• Temperature can vary (hot or cold)

• Small in size

Kayla Woodsum

Medium Mass Star

Sun

• Lives by fusing the hydrogen within the core into helium (nuclear fusion

reactions)

• Surface temperature is 5000 degrees Celsius

• Center core temperature is 15600000 degrees Celsius

• 1390000km in diameter, over 100 times the diameter of Earth

• Yellow in color

• 3 main layers: core, radiative zone, convective zone

• Evolve by turning into red giants and undergoing a core helium burning

phase

• Made of 70% hydrogen, 28% helium, 2% of metals such as iron

• Mass = 2 x 1030 kilograms, 300000 times greater than Earth

• 149600000km (92 million miles) from Earth

• Makes up 99.86% of solar systems mass, provides energy that both

sustains and endangers us.

• Standing on the sun makes you feel 38 times heavier than on Earth

• Once the core collapses a shock wave forms and blasts out the outer layers

brighten rapidly and are ejected at speeds approaching the speed of light,

turning into a supernovae

Meghan Griswold

Planetary Nebula

o Forms when a star can no longer support itself by fusion reactions in its center.

o Color-Variety of colors o Temp-10,000 K o Size-One light year across. Consists of

extremely rarefied gas, with a density generally around 1000 particles per cm!.

o Fuel-Hydrogen and helium (Nuclear Fuel) o Anatomy-Oxygen, nitrogen, carbon, and

sulfur o

• Collapses and creates new stars

HyperGiant By Leah Brown

! Largest and brightest known stars

! Made of hydrogen, helium, carbon,

neon, and oxygen…. later on silicon right before supernova

! Can be up to 40 million times brighter

than the sun

! Have a diameter between 100 and 2100

times that of the sun

! Canis major is the largest known hypergiant

! There are red, blue, and yellow

hypergiants

! Last for a few million years till they

supernova ! Supernovas in hypergiants happen after

silicon fuses with their iorn core

A reflection nebula is a cloud of dust that reflects’ the light of a nearby star or stars.

• Like fog around a street lamp, a reflection nebula shines only because the light from an embedded source illuminates its dust; the nebula does not emit any visible light of its own.

• A reflection nebula that can be seen surrounds the stars of the Pleiades.

• Also the giant star Antares is surrounded by a large, red reflection nebula.

Savannah Richardson

Reflection Nebula

Low Mass Stars

This is the inside of a low mass star

Joe Pelletier

FACTS

! Low mass stars start life as

part of an interstellar cloud

! The cloud picks up dust and

space junk over time

! The cloud collapses as a

result of gravity

! As it collapses it gets

smaller and hotter

! The Low mass type star

burns at a temperature

slightly higher than that of

the sun

! The fuel of the low mass

star is primarily helium

! The low mass star has

various colors ranging from

blue, orange, yellow, etc...

! Most low mass stars are

relatively the same size as

the sun.

Evolution of a Low Mass Star

! Hydrogen shell continues to

fuse

! Helium ash builds up in the

core

! Pressure and temperature

rise

! The ash in the core turns to

carbon ash

! The carbon ash compresses

! The outer layers flex and

shed the planetary nebula

! Then the carbon core (white

dwarf) remains.

This is the late stage of low mass

star evolution.

Dark

Nebulae

• Formed from the result of supernovas exploding stars

• The Nebulae is then formed from the excess gas and dust

• Largest dark nebulae can be seen by the naked eye

• Some of the largest nebulae are a million times as big as the sun

• They are dark like shadows, sometimes darkish red, they block the light from

behind

• Can be 150 light-years across

• 100 to 300 molecules per cubic centimeter

• - 447 to – 432 degrees below Fahrenheit

• Stars are formed in Dark Nebulae

• Horsehead Nebula is the most famous

• Radiation is released often

Interstellar Medium

Definition)-In astronomy, the interstellar medium (or ISM) is the gas and dust that take up interstellar space: the matter that exists between the stars within a galaxy.

It fills interstellar space and blends smoothly into the surrounding intergalactic

space.

The interstellar medium.

• Gas in the Interstellar Medium • Of the gas in the Milky Way, 90% by mass is hydrogen, with the remainder

mostly helium. The gas appears primarily in two forms

• Cold clouds of atomic or molecular hydrogen • Hot ionized hydrogen near hot young stars

• The clouds of cold molecular and atomic hydrogen represent the raw

material from which stars can be formed. • Interstellar dust grains are approximately the wavelength of blue light,

irregularly shaped, and composed of carbon and/or silicates.

• These dust clouds are visible if they absorb the light coming through them. • We then refer to these clouds as dark nebulae such as the adjacent

Horsehead Nebula.

• On the other hand, light can reflect from clouds of dust and gas.

• The dust dims the light. • The light that does pass through the dust is depleted in blue wavelengths

because the size of the dust grains favors scattering blue light.

• This is called interstellar reddening, because the transmitted light is redder than it would have been.

• On Earth, the blueness of the sky is due to similar effects in scattering of

light from molecules in the atmosphere. • Temperatures of all components. HI gas ~5 x 109 0.1-10 100-1000)- H2 gas

1-5 x 109 105-106 103-105 ~10)-Dust ~5 x 107 ~40)- HII gas 100-1000 103-104

10,000

• The colors range from red blue brown and black.

Protostar

• A protostar is a phase that each star goes through when it becomes a star.

• The center of this star formation reaches a

temperature of 10,000,000 degrees celcius.

• The temperature increases as the star cloud continues to contract in size.

• The size of a protastar can be almost 10 times the size

of the sun.

• Once a protostar uses up its fuel, it begins to cool and it will eventually shrink.

• Colors are usually close to red.

Dylan Stuart