SPACE SCIENCE

Space Science
encompasses all of the scientific disciplines that
involve space exploration and study natural
phenomena and physical bodies occurring in outer
space
1 Solar system 2 Stars

Sun Characteristics of a Star

Planets Formation of a Star
Dwarf planets Constellations
Asteriods
Meteors
Comets
 1
Solar System
Our planetary system is located in an outer spiral arm of the
Milky Way galaxy.

Our solar system consists of our star, the Sun, and

everything bound to it by gravity — the planets Mercury,
Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune,
dwarf planets such as Pluto, dozens of moons and millions of
asteroids, comets and meteoroids.
 FORMATION
OF THE SOLAR
SYSTEM
Our solar system formed about 4.5 billion years ago from a dense
cloud of interstellar gas and dust.
The cloud collapsed, possibly due to the shockwave of a nearby
exploding star, called a supernova.
When this dust cloud collapsed, it formed a solar nebula—a
spinning, swirling disk of material.
At the center, gravity pulled more and more material in. Eventually
the pressure in the core was so great that hydrogen atoms began to
combine and form helium, releasing a tremendous amount of
energy. With that, our Sun was born, and it eventually amassed
more than 99 percent of the available matter.
A. SUN
The sun is the most prominent feature in our solar
system.

It is the largest object and contains approximately

98% of the total solar system mass.

The sun is the nearest star to Earth.

The interior can hold over 1.3 million Earths. It is
about 547 km thick
All the planets in our solar system orbit the
sun, in turn, our solar system orbits the
center of our galaxy, the Milky Way. It
takes about 225 million years or one
cosmic year for the sun and the eight
planets to travel around the milky way.
PARTS OF THE
SUN
PHOTOSPHERE
The surface of the sun. its
temperature is around 5500 ºC.
The photosphere is not solid,
but it is the sun’s visible outer
edge.
 SUNSPOTS
Are darker, cooler areas on the
sun’s photosphere, ranging in size
up to thousands of kilometers
across. The spots are caused by
strong magnetic fields within the
sun that slow down the flow of the
heat from inside.
 FLARES
The sun’s surface is a violent place,
and it regularly releases short-lived
bursts of energy
 PROMINENCES
Large eruptions, stretch for many
thousands of kilometers into the
sun’s atmosphere and can last for
months
CHROMOSPHERE
A layer of hydrogen and helium,
about 1500 km thick.
 CORONA
Outer layer of the sun’s
atmosphere, where the temperature
is about 1000,000 ºC.

At this temperature, the particles of

gas are hot enough to escape the
sun’s gravity and they begin to flow
outward into space at a speed of
5000 km.
 SOLAR WIND
The constant stream of particles
which travels through the solar
system.
IMPORTANCE
OF THE SUN
 It supplies us with heat
and light, and it is the
main source of energy in
our planet.

It provides light to most

of the planets.
Its gravitational pull is what holds Earth and
all the other planets together.
 It provides plants with the
energy to grow and produce
oxygen for us to breathe

It provides energy and is

responsible for the photosynthesis
that is needed for the food-making
process of the plants.
It is the prime source of energy that we get
from the food that we eat.
 It provides the
earth with energy
that enables it to
generate the
electricity needed
and is used by
many homes and
establishments
The ROLE of the
SUN in the Solar
System
Our sun is the gravitational anchor that
keeps the planets, asteroids, comets,
and other members of the solar system
orbiting around it, which are strongly
attracted to the sun’s huge mass. This
gravitational attraction keeps these
bodies in the orbit around the sun.
 The region which the solar wind
blows is the heliosphere. It is
estimated to be ranging from 86
The sun also influences the solar to 100 times the distance
system with its diffuse outer between Earth and Sun.
atmosphere that expands outward in
all directions. This expanding
atmosphere fills the solar system with
a constant flow of tiny, fast,
electrically charged particles. This
flow is called solar wind. It also carry
remnants of the sun’s magnetic field,
which affects the planets and larger
satellites’ magnetic fields.
The ROLE of the
SUN in the
Water Cycle
 During the process of the water cycle, the following
processes take place:

1. The sun provides thermal energy to the earth’s surface

water, which is the key to evaporation.
2. The sun heats bodies of water (rivers, lakes, and
oceans), which then evaporates into the atmosphere
and becomes water vapor.
3. The water vapor then condenses and cools, becoming
precipitation like rain, snow, and sleet before falling
back to Earth.
EFFECTS of the
SUN on Living
Things
 Ultraviolet (UV) radiation
from the sun has always
played important roles in our
environment and affects
nearly all living organisms,
which include plants,
animals, and human beings.
PLANETS
 Terrestrial Planets/Inner Planets

a planet that is composed primarily of silicate rocks or metals.

 MERCURY

The closest planet to our sun

and the smallest planet in the
solar system.

It is also the second densest

major body in the solar system
after Planet Earth and its
density is slightly less than the
Earths.
The Greeks gave it two names: Apollo
for when it appeared as a morning star
and Hermes when it came as an
evening star.

In Roman mythology Mercury is the god

of commerce, travel and thievery, the
Roman counterpart of the Greek god
Hermes, the messenger of the Gods.
The planet probably received this name
because it moves so quickly across the
sky
It has no natural satellites and The planet rotates once about
no substantial atmosphere. every 59 Earth days, a rotation
slower than that of any other
Its orbit is most elliptical planet except Venus.
Orbiting the Sun once every 88 As a result of the planet's slow
days. rotation on its axis and rapid
movement around the sun, a
Temperature: ? day on Mercury lasts 176 Earth
days (interval between one
Time to Rotate: 58.6 days sunrise and the next).
Mass: 3.30e23 kg (5.5% of
Earth's)
Explorations on Mercury
Mariner 10 : Planet Mercury was explored in three flybys by
the Mariner 10 spacecraft in 1974 and 1975.

In the future, NASA is planning to explore Mercury with the

MESSENGER Spacecraft and Europe/Japan with
BepiColombo.R Spacecraft.

In 2004, the United States launched the Messenger probe to

Mercury. Messenger was scheduled to fly by Mercury twice in
2008 and once in 2009 before going into orbit around the
planet in 2011. The probe was then to orbit Mercury for one
Earth year while mapping Mercury's surface and studying its
composition, interior structure, and magnetic field.
 VENUS
The second closest planet to the sun.
It is located between our Earth and
Mercury.

It is named after the Roman goddess

of love and beauty.

The hottest planet.

Venus was often considered a "twin
sister" to the Earth because Venus is
the nearest planet to us, and because
superficially the two planets seem to
share many characteristics.

Venus is the brightest object in the sky

besides our Sun and the Moon. It is
also known as the morning star
(Phosphorus or Lucifer) because at
sunrise it appears in the east and and
evening star (hesperus) as it appears
at sunset when it is in the west. It
cannot be seen in the middle of the
night.
Temperature: Ranges Rotation of its axis: 243 Earth days (1
from 900F+/- 50F (about Venusian Day)
500°C +/- 32°C) at the
surface Rotation around the Sun: 225 Earth
days
Atmosphere: Carbon
dioxide (95%), nitrogen, Magnetic Field: No
sulfuric acid, and traces
Venus is covered with thick clouds that
of other elements
create a greenhouse effect that makes
it very hot.
Surface: A rocky, dusty,
waterless expanse of Venus has no moons.
mountains, canyons, and
plains, with a 200-mile Venus rotates from east to west
river of hardened lava (retrograde - opposite to that of earth).
If you were on Venus, the Sun would
rise in the west and set in the east.
 Explorations on Venus
The first spacecraft to visit Venus was Mariner 2 in 1962.
It was subsequently visited by many others (more than 20
in all so far), including Pioneer Venus and the Soviet
Venera 7 the first spacecraft to land on another planet, and
Venera 9 which returned the first photographs of the
surface. The first orbiter, the US spacecraft Magellan
produced detailed maps of Venus' surface using radar.
ESA's Venus Express is now in orbit with a large variety of
instruments.
Comparison between Earth and
Venus
• The slow rotational period.

• The single-plate surface.

• The lack of a satellite or moon.

• The extremely weak magnetic field.

• The lack of water.

• The high surface temperature and dense

atmosphere.
 EARTH

The third planet from the Sun

and the fifth largest planet in
the solar system.
 Surface: 71% of Earth's surface is covered in
Atmosphere: 78%
water.
Nitrogen, 21% Oxygen and
trace amount of Argon, Carbon
Temperature Range: -69 °C to 58 °C.
Dioxide, Helium, Hydrogen,
Methane.
Age: more than 4.5 billion years old.
Natural Satellites: 1 - the Moon
Orbital path: elliptical
(oval shaped)
Earth Year: 365 ¼ days
(revolution around the sun)
Axis of Rotation: 23.5°
Earth rotation : 24 hours or 1
day
 Characteristics of
Earth
A.Mass- most of its mass is in the
mantle and core. It is the densest planet.

atmosphere = 0.0000051
oceans = 0.0014
crust = 0.026
mantle = 4.043
outer core = 1.835
inner core = 0.09675
 Chemical Composition of Earth

34.6% Iron
29.5% Oxygen
15.2% Silicon
12.7% Magnesium
2.4% Nickel
1.9% Sulfur
0.05% Titanium
 B. 71% of the Earth's surface is covered with water.
Liquid water is essential for life. The heat capacity of
the oceans is also very important in keeping the Earth's
temperature relatively stable. Liquid water is also
responsible for most of the erosion and weathering of
the Earth's continents.

C. Earth has a modest magnetic field produced by

electric currents in the outer core. The interaction of
the solar wind, the Earth's magnetic field and the
Earth's upper atmosphere causes the auroras .
MOTION OF THE
EARTH

Rotation is the movement of object on its

axis. Earth rotates from west to east
(counterclockwise).The period of one
complete rotation is 23 hours, 56 minutes,
and 4.2 seconds.

APOGEE
PERIGEE
 EFFECTS OF THE
ROTATION OF THE EARTH
Earth’s rotation may result to the occurrence of day
and night. The length of daytime and nighttime
varies as Earth revolves around the sun.

The sun rises in the east and sets in the west, as do

the moon, planets, and the stars. These daily
motions are the result from Earth’s rotation.

Earth’s rotation affects the flow of air and water on

Earth. Flowing air and water are diverted from north
south direction to an east-west direction because of
Earth’s rotation. The diversion of direction is called
the Coriolis Effect.
Revolution is the movement of an object
around the bigger object.

Earth revolves around the sun. Its orbit

around the sun is in the form of a slightly
flattened circle called an ellipse.

Perihelion – earth is closest to the sun.

Aphelion – earth is farthest from the sun

EFFECTS OF THE
REVOLUTION OF THE
EARTH

Occurrence of seasonal
changes – the seasons
change through the year; the
length of days varies; and the
temperature may range from
cold to hot depending on the
latitude where you live.
 MOON

The Earth’s only natural

satellite
 It has a black sky, has almost no atmosphere
Our Moon is bigger than Planet
due to its weak gravity. Without an
Pluto.
atmosphere, there is no wind, no clouds and no
rain.
Galileo in 1609 was the first to
look at it through a telescope.
The Moon shines by reflecting the light of the
Sun. Although it appears bright, it reflects on
The Moon is about 4 and a ½
average only 12 percent of the light that falls on
billion years old.
it.
The moon is about one quarter
(1/4) the size of Earth and it has
about one-sixth of the Earth's
gravity.
Mass: 7.35 X 1022 kg. This about one-
eightieth of the Earth's mass.

Moon's rotation: Rotates about its own

axis in 27 days and 8 hours or 27 1/3
days, which is about the same time it
takes to orbit the earth. Hence the same
face of the moon is always facing the
Earth. The far side always faces away
and cannot be seen from Earth.

Moon Surface: It is covered with craters,

lava plains, mountains and valleys. No
active volcanoes.
Maria- (Latin for “seas”) dark regions on the
face of the Moon but these regions are
now known to be completely dry

The largest of the maria is Oceanus

Procellarum, an oval-shaped plain on the
near side of the Moon 2,500 km by 1,500
km wide.

Craters - circular indentions on the

Moon’s surface
 Explorations on the Moon
The Russian spacecraft Luna 3 in 1959 radioed back
the first photograph of the moon’s far side. Because of this success,
the United States was motivated to have the Apollo Project, which
was to place an astronaut on the moon before 1970.

All six manned landings on the Moon—Apollo 11, 12, 14,

15, 16, and 17—returned samples of rock and soil to Earth.

Apollo 11- first steps on the moon ( Neil Armstrong and

Edwin Aldrin)

Neil Armstrong “ One small step for man, one giant leap for
mankind”
 Movement of the Moon
The moon completes one rotation
in one complete revolution. So the time it
takes to fully rotate is the same time it takes
to revolve. The moon rotates on its axis one
1
and revolves around the sun every 27 days.
3
Because these two movements take the
same amount of time, the same side of the
moon always faces Earth. A day on the moon
is equivalent to two Earth weeks. After two
weeks, the moon starts to be in darkness.
This lasts for another two weeks. The lunar
1
day is 27 Earth days with about 14 days of
3
daylight and 14 days of darkness.
 Phases of the Moon

As the moon orbits Earth,

it appears to have different shapes.
These are called phases. The
moon’s phases are the changing
appearances of the moon as seen
from Earth. The phases of the
moon are determined by the
relative positions of Earth, the
moon, and the sun.
 Eclipse

Eclipses can be predicted

because they happen only when
Earth, the sun, and the moon are in
a straight line. An eclipse occurs
when one object moves into the
shadow cast by another object.
SOLAR ECLIPSE
Observers within that shadow on
Earth see the sky turn dark as the
moon blocks out the sun. This is
called a solar eclipse. During a
total solar eclipse, you can see a
ring of light around the moon. The
places that receive the darker side
of the shadow, which is called the
umbra, will experience a total solar
eclipse while those places that
receive the penumbra side of the
shadow will have the partial
eclipse.
LUNAR ECLIPSE

When the moon is

full, it may pass into
the shadow of Earth.
Observers on Earth
can see the full moon
become temporarily
darken as it passes
through Earth’s
shadow.
 TIDES
Tides pertain to the regular rise
and fall in the level of the ocean
water.

Earth’s rotation causes the

formation of two tides and two
low tides each day. If Earth
does not rotate, high and tides
occur every two weeks as the
moon passes into the different
positions in its orbit.
 SPRING TIDE
Twice each month, the high and the
low tides are respectively higher and
lower than usual. This occurs during
new moon and full moon. At such
times, Earth, sun, and moon fall in
line. The gravitational pull of the sun,
although weaker than that of the
moon because of its great distance,
also causes the formation of bulges
on Earth. As a result, the tidal effect
of the moon and the sun are added
together.
 NEAP TIDE
Twice a month, the high tides are
lower than usual and the low tides
are higher than usual. This
happens during the first and last
quarter phases of the moon. The
sun, Earth, and the moon are at a
right angle with each other. The
gravitational pulls of the sun and
moon tend to cancel each other.
 MARS

The fourth planet from the Sun

and the seventh largest planet
Mars is named for the Roman god Martian surface temperatures range
of war. widely from as little as 140 K (-133 C,
-207 F) at the winter pole to almost
It is also called the red planet 300 K (27 C, 80 F) on the day side
because it appears fiery red during summer.
caused by iron(III) oxide, more
commonly known as hematite, or
rust

Less dense than Earth

Though Mars is much smaller than

Earth, its surface area is about the
same as the land surface area of
Earth.
Mars has a very thin atmosphere
composed mostly of

carbon dioxide (95.3%)

nitrogen (2.7%),
argon (1.6%) and
traces of oxygen (0.15%) and
water (0.03%).
 Its surface, peppered with vast The solar day (or sol) on Mars/ one
volcanoes such as Olympus complete rotation is only slightly longer than
Mons and rift valleys such as an Earth day: 24 hours, 39 minutes, and
Valles Marineris, shows 35.244 seconds.
geological activity that may have
persisted until very recently.

Revolution around the sun is 687

(Earth) days or 23 Earth months

A Martian year is equal to

1.8809 Earth years, or 1 year,
320 days, and 18.2 hours
Olympus Mons
the highest
mountain/volcanoes in the
solar system, at 27km
Its axis is tilted at 25° angle Both satellites were discovered in 1877
by Asaph Hall, and are named after the
Mars's seasons are the most Earth-like, characters Phobos (panic/fear) and
due to the similar tilts of the two Deimos (terror/dread).
planets' rotational axes

Mars has two tiny natural satellites

(Deimos and Phobos)

Deimos ("DEE mos") is the smaller and

outermost of Mars' two moons. It is one
of the smallest known moons in the
solar system.
Explorations on Mars
The Viking 1 and 2 space probes arrived
on Mars in 1976 with an orbiter and a
lander. The orbiters took photographs of
the surface of Mars. The landers touched
down on Mars and carried equipment
designed to detect the possible life on
Mars and to analyze gases given off by
Martian soil.
 JUPITER

The fifth planet from the Sun

and the largest planet in
the solar system
A gas giant is a giant planet composed mainly
of hydrogen and helium. Gas giants are
sometimes known as failed stars because they
contain the same basic elements as a star.

It do not have solid surface, its gaseous

material simply gets denser with depth

Jupiter is about 90% hydrogen and 10% helium

with traces of methane, water, ammonia and
"rock". This is very close to the composition of
the primordial Solar Nebula from which the
entire solar system was formed. Saturn has a
similar composition, but Uranus and Neptune
have much less hydrogen and helium.
Jupiter is more than twice as massive as
all the other planets combined (the mass
of Jupiter is 318 times that of Earth).

Jupiter is the fourth brightest object in

the sky (after the Sun, the Moon and
Venus).

One complete revolution: 11.86 years

One complete rotation: less than 10

hours/is 9h 55m 40.6s

Surrounding the planet is a faint

planetary ring system and a powerful
magnetosphere.
Jupiter and the other gas planets have
high velocity winds which are confined
in wide bands of latitude.

Slight chemical and temperature

differences between these bands are
responsible for the colored bands that
dominate the planet's appearance. The
light colored bands are called zones;
the dark ones belts.
The outer atmosphere is visibly
segregated into several bands at
different latitudes, resulting in
turbulence and storms along their
interacting boundaries.
Great Red Spot
A prominent result is the Great Red Spot,
a giant storm which can hold 2 earths.
It has least 63 moons, including the
four large moons called the Galilean
moons that were first discovered by
Galileo Galilei in 1610. Ganymede,
the largest of these moons, has a
diameter greater than that of the
planet Mercury.
 GANYMEDE CALLISTO
largest of Jupiter's known satellites the second largest. It is the
the third of the Galilean moons outermost of the Galilean moons.
 IO EUROPA
the third largest; it is the innermost the fourth largest; it has a thin
of the Galilean moons outer layer of ice. Europa's surface
It has active volcanoes is exceedingly smooth
Explorations on Jupiter
Pioneer 10
Pioneer 11
Voyager 1
Voyager 2
Ulysses
Cassini
New Horizons
 SATURN

The 6th planet from the Sun and

the 2nd largest planet and
famous for its beautiful rings.
 It has at least 31 moons. These include
Titan, Hyperion, Mimas, Enceladus,
Rhea, and Phoebe.

Diameter: 120,660 km. It is about 10

times larger than our Earth

Temperature: –178°C

Rotation of its axis: 10 hours, 40 min, 24

sec

Rotation around the Sun: 29.5 Earth years

 TITAN
largest moon of Saturn
second to Ganymede

has an atmosphere of
nitrogen, argon, and
methane
 The outer atmosphere of Saturn consists of
about 96.3% molecular hydrogen and 3.25%
helium. Trace amounts of ammonia, acetylene,
ethane, phosphine, and methane have also
been detected.

Saturn's hazy yellow hue is marked by broad

atmospheric banding similar to, but fainter than,
that found on Jupiter.

Saturn is the only planet of the Solar System

that is less dense than water. Although Saturn's
core is considerably denser than water
Saturn's ring system makes the planet
one of the most beautiful objects in the
solar system composed of mostly of ice
particles with a smaller amount of rocky
debris and dust.
 URANUS

The third largest planet in the

solar system and is the
seventh planet from the
sun.
Uranus is an ice giant. Most of its mass is a hot,
dense fluid of "icy" materials – water, methane and
ammonia – above a small rocky core.

Uranus' atmosphere is about 83% hydrogen, 15%

helium and 2% methane. There are also traces of
water and ammonia. The methane gas above the
cloud layers gives it a blue-green colour.

It was initially named as “the Georgium Sidus"

(the Georgian Planet)

Uranus is the only planet in our Solar System to

spin on its side. The axis of rotation tilt is 98
degrees. The severe tilt to its rotational axis may
have resulted from a great collision long ago.
It was discovered by William Herschel on March
13, 1781

Temperature: -197.15 C (-322.87° F)

Revolution: Takes 84 years to complete an

orbit.

Moons: 27

Period of Rotation: 17.24 hours (retrograde:

spins backwards compared to most other
planets)
It is the coldest planetary atmosphere in
the Solar System

The rings are composed of extremely

dark particles, which vary in size from
micrometers to a fraction of a meter.
Thirteen distinct rings are presently
known, the brightest being the ε ring.
 TITANIA
largest moon of Uranus
 Explorations on
Uranus

Voyager 2 is the only spacecraft to

fly by Uranus. No spacecraft has
orbited this distant planet to study it
at length and up close.
NEPTUNE

The 8th and the outermost-

known planet in the solar
system. It is also known as
the Blue Giant
it is the fourth-largest planet by diameter and
the third-largest by mass.

Near twin planet of Uranus

It was discovered by Urbain Le Verrier, John

Couch Adams and Johann Galle

Number of known satellites: 8

Length of Year or revolution: 164.8 Earth-years

Length of Day or rotation: 16.11 hours, 0.67

Earth-day
Atmospheric components: 74% hydrogen,
25% helium, 1% methane

As with Uranus, this absorption of red light by

the atmospheric methane is part of what
gives Neptune its blue hue, although
Neptune's vivid azure differs from Uranus's
milder aquamarine.
Neptune's weather is
characterized by extremely
dynamic storm systems.

GREAT DARK SPOT

 TRITON
the largest moon of
Neptune and discovered
by William Lassell.

Unlike all other large

planetary moons in the
Solar System, Triton has a
retrograde orbit, indicating
that it was captured rather
than forming in place
known to have “ice volcano”
 Explorations on
Neptune

Neptune has been visited by only

one spacecraft, Voyager 2 on Aug
25 1989. It was the last stop in 1989
for the Voyager 2 spacecraft on its
grand tour of the solar system.
DWARF PLANETS
 PLUTO
Pluto was considered the ninth planet in the
solar system until 2006. In the early 21st century,
many objects similar to Pluto were discovered in
the outer solar system. In August 2006, the
International Astronomical Union (IAU) defined
the term planet and excluded Pluto from the list.
Pluto was reclassified as a member of the new
category of dwarf planets.

Pluto's rotation period- 6.387 days

Revolution- 249 year orbit.

It was the first and only planet to be
discovered by an American, Clyde W.
Tombaugh.

Pluto orbits beyond the orbit of Neptune

(usually).

Pluto is smaller than seven of the solar

system's moons (the Moon, Io, Europa,
Ganymede, Callisto, Titan and Triton).

Pluto's orbital period is exactly 1.5 times

longer than Neptune's.
Due to the eccentricity of its orbit, it is
closer than Neptune for 20 years out of its
249 year orbit.
Charon- is the pluto’s largest satellite

Charon was discovered in 1978 by Jim

Christy

Pluto has an icy surface, which is composed

of 90% nitrogen and 8% carbon dioxide and
2% methane.

Data from the Hubble Space Telescope

shows that there is a vast disk of icy objects
beyond the orbit of Neptune. The vast icy
objects are known as the Kuiper Belt. One
object found is about 1,300 km in diameter.
Many astronomers think that Pluto and
Charon are members of the Kuiper Belt.
 ERIS
Eris was discovered in July 2005 by
astronomer Mike Brown. It was almost 10
billion miles from the sun, located in the
orbit around the sun beyond Neptune.
Eris was called then as UB 313 or Xena
by the Astrophysical Institute and
University before it was officially named
as Eris.

Orbital period- 203,600 days or 557 years

Satellite- one (Dysnomia)

Found in the scattered disc
The largest known dwarf planet in the
Solar System
 CERES
It was discovered by G. Piazzi on January
1, 1801 (45 years before Neptune)

considered a planet for half a century

before reclassification as an asteroid.

Classified as a dwarf planet on

September 13, 2006.

While the asteroid belt is composed

primarily of rock and metal
the Kuiper belt objects are composed
largely of frozen volatiles (termed "ices"),
such as methane, ammonia and water.
SMALL SOLAR SYSTEM
BODIES
 ASTEROID
Asteroids, also known as
planetoids, are small pieces of
rocks and metals that orbit around
the sun between Mars and Jupiter.

Asteroids that crash into Earth are

known as meteors. Sometimes
asteroids change orbit and move
out of the asteroid belt. These
asteroids cross the orbit of planets
as the planets go around the sun.

Formed in the Asteroid belt

 METEORS
A meteor is a bright streak of light in the sky (a
"shooting star" or a "falling star") produced by the
entry of a small meteoroid into the Earth's
atmosphere.

Meteoroids are pieces of dust and rocks that

break from a comets nucleus. When a meteoroid
enters Earth’s atmosphere, pieces of rocks and
dust are burned. The burning rocks that enter
Earth’s atmosphere are called meteors. When
more meteors are seen in the atmosphere, the
event is called a meteor shower. Some
meteoroids are large enough and do not burn up
completely in the atmosphere. If this big
meteoroid reaches Earth’s surface, it is called
meteorite.
METEORITES
 COMETS
Comets are sometimes called dirty snowballs or
"icy mudballs".

A comet is made up of dust and rock particles mixed

with frozen water, methane, and ammonia. Comets
also orbit around the sun. as a comet approaches
the sun, the sun’s rays heat it up. The heat causes
the frozen rocks and dust to melt and evaporate. The
molecules are blown away from the comet by the
action of solar wind. The ice particles of the comet
brighten enormously and develop a brilliant tail. The
tail is generally directed away from the Sun, even as
the comet returns.
Parts of a Comet
 HALLEY’S COMET

Edmond Halley predicted, using Newton's

newly formulated laws of motion, that the
comet seen in 1531, 1607, and 1682 would
return in 1758 (which was, alas, after his
death). The comet did indeed return as
predicted and was later named in his honor.
STARS
 STAR
A star is a hot ball of glowing gases. It is formed as a
result of the force of gravity acting on particles and
dust in an area of space.

Stars are used in telling directions. Without an

instrument, you can tell Earth’s north, south, east, and
west sky by looking at the stars and constellation. The
Polaris tells where Earth’s north location is. Rigel is
the brightest star of the Orion constellation that is
visible from January to March. It can tell Earth’s east
and west because it seems to move from east to
west. Our Sun, which is a yellow star, tells where the
east and west directions are. The sun rises in the east
and sets in the west.
 FORMATION OF A STAR
A star is born in a low-density cloud of dust
and gas called nebula. The nebula contains an
abundant amount of hydrogen atoms. As the particles
of the cloud begin to attract each other and form
larger masses, the temperature of the nebula rises.
When the temperature in the nebula reaches up to 10
million degrees Celsius, nuclear fusion begins.

Hydrogen atoms fuse together in the

process called thermonuclear reaction to become
helium. When the outward push from the fusion and
the inward pull from the gravity balance, a star is born.
Energy from the fusion produces light that reaches the
surface. This is what we see on Earth as starlight.
When the hydrogen in the core is used
up, the core collapses, causing the
temperature to rise even more. The
energy makes the outside of the stars
swell. As the star grows bigger, it cools.
Cooler stars look red. Thus, a red star
is called a red giant star or a
supergiant star. A red giant can be a
hundred times bigger than the sun.

https://www.youtube.com/watch?v=EF
O_bsg1sw8
 STARS VARY IN MASS
Mass is the amount of matter in an
object. Stars are usually made of around 80%
hydrogen, 18% helium, and the remaining
amounts are elements like copper, nickel, iron,
calcium, sodium, and aluminum.

The mass is an important factor that

will determine what a star will be. The time it will
go through at different stages will depend on its
mass. The stars that have high mass have short
lives that usually end in a supernova explosion
while low mass stars have longer lives and
usually end as white dwarfs.
 STARS DIFFER IN SIZE
Supergiants – they are the largest stars. Ex. Are Antares and Betelgeuse. Antares
has a diameter that is 330 times that of the sun. Betelgeuse has a diameter of 375
to 595 times that of the sun.

Giants – they have diameters that are about 10 to 100 times larger than the sun’s.
Aldebaran has a diameter that is 36 times that of the sun.

Medium-sized Stars – they are as big as the sun. Other stars in this group are
Altair, Sirius, and Rigel.

White Dwarfs – they are the small stars. The smallest dwarf is Van Maanin’s star.
It has a diameter of 8,370 km, less than the distance across Asia.

Neutron Star – they are the tiniest stars. Their mass is less than that of the sun but
is so compact. Their diameter is about 20 km.
 Stars Differ in Color and Temperature
Stars differ widely in color. A star color is a guide to its temperature. Red stars
have the coolest temperature, and blue stars have the highest temperature.
Astronomers classify stars according to the characteristics of the light that the
stars emit. The color also tells which star is the hottest. O stars are the hottest
and M stars are the coolest. Our sun is a G star, which it is a hot star.
 Stars Differ in Brightness
The brightness of stars is measured using absolute magnitude and apparent
magnitude as bases. Magnitude allows astronomers to rank how bright stars
appear to humans. Magnitude is given in terms of absolute and apparent
values.

Absolute magnitude is a measurement of how bright a star would appear if

viewed at equal distances with other stars. The sun’s absolute magnitude is
4.8. The brightest known stars have absolute magnitudes of about -9, and the
dimmest known stars have absolute magnitudes of about 20. The lower the
star’s magnitude, the brighter it is. Stars with negative magnitudes are the
brightest of all.
CONSTELLATIONS
A group of stars that form a certain pattern
is called a constellation. Today,
astronomers listed a total of 88
constellations.
NORTH HEMISPHERE
Ursa Major, Ursa Minor, and
Cassiopeia are constellations visible in
the north sky. As Earth rotates, the
constellations circle around Polaris.
Because of this, they are called
cimcumpolar constellations. Polaris
is located at the end of the little dipper
in the constellation Ursa Minor. Near
the celestial pole is a group of five
stars facing Polaris, forming a rough
letter W or a big M depending on the
season. This constellation is called
Cassiopeia.
Ursa Major Ursa Minor Cassiopeia
 EAST
The Orion constellation is located at the celestial equator east of
Taurus. It is visible from January to March. It is named in Greek
mythology as the hunter.

Orion
 USES OF
CONSTELLATIONS
 Constellations tell general directions

Constellations are useful to navigators. Ursa Minor, Ursa

Major, and Cassiopeia are constellations that are used by
navigators to tell the north directions. Polaris, found at the
last star of the handle of the Little Dipper, tells north. It is
visible in the northern hemisphere. This star is pointing
toward the axis of Earth. It gives direction and location of
the north celestial pole.

The Orion constellation tells Earth’s east and west sky.

The Southern Cross or Crux constellation is located at the

southern hemisphere. It contains four bright stars so
situated that they depict the extremities of a Latin cross.
This constellation tells the south sky.
Constellations measure and tell seasons

The 12 constellations which we called as the

Zodiac keep a definite circular belt or path in the
sky. Sagittarius, Capricorn, and Aquarius are
visible during winter. Pisces, Taurus, and Aries
are visible during the spring season. Gemini,
Cancer, and Leo are visible during summer.
Virgo, Libra, and Scorpio are visible during
autumn.

The Zodiac is an imaginary belt or path in the

heavens that includes the paths of the planets.
The different constellations can be seen in a
particular month and season.
Constellations are used to locate stars
and galaxies

Constellations are used by astronomers to

locate stars, nebulae, and galaxies. The Flame
Nebula, also called NGC 2021, is a region of
dust and gas in the constellation Orion. The
Horsehead Nebula is also in the Orion
constellation. This dark nebula is visible from
Earth only because it blocks light coming from
young stars located behind the nebula.
Astronomical Instruments
 Optical Telescope

The telescope used by Galileo is an optical

telescope. Optical telescopes collect visible
light from the outer space. These telescopes
come in two varieties: the refracting and
reflecting telescope. The refracting telescope
collects and focuses light into a glass lens and
focuses light directly into the eyepiece, while
the reflecting telescope reflects light on a glass
mirror and sends it to the eyepiece.
 Radio Telescope

Radio telescopes have very sensitive

receivers with wide antennas. With
them, astronomers can study objects
too far to be seen by ordinary
telescopes by detecting the radio
waves the objects give off.
 Satellites

Hundreds of artificial satellites have leapt into orbit

since 1957. Satellites also have a great impact on
human life by tracking weather and providing fast
phone, TV, and radio communication. Other
satellites are astronomical observatories looking at
distant stars and galaxies. Satellites can also study
cosmic rays and high-frequency radiation from
deep space, and learning about supernovas and
neutron stars. Probes to other planets provide
pictures and measurements of the strange worlds
nearby.
Suggested Strategies in
Teaching Space Science
 Creating Models or Realia
is a term for real things – concrete
objects- that are used in the classroom
to build background knowledge and
vocabulary. Realia is used to provide
experiences on which to build and to
provide students with opportunities to
use all the senses in learning. Ex.
Solar system, planets, moon, galaxy,
constellations, and spacecraft.
tours usually are outside classroom activities that promote
active learning and demonstrate real-world operations. In
gallery walk, students explore multiple texts or images
placed around the room. You can use this strategy when
you want to have students share their work with peers,
examine multiple historical documents, or respond to a
collection of quotations. Because this strategy requires
students to move around the room, it can be engaging to
kinesthetic learners. On tour, it can be a video, slide
presentation, or an interactive 3D Tour of the Solar System.

Tour/Gallery Walk
 Making Simulation

is the imitation of the operation of a

real-world process or system over
time. Simulations require the use
of models; the model represents the
key characteristics or behaviors of
the selected system or process,
whereas the simulation represents
the evolution of the model over time.
Example: revolution of the planets
around the sun, effects of UV rays
from the Sun, the reasons for
Seasons, rotation of the moon and
others.
 Gamification
developing approach for increasing
learners’ motivation and engagement
by incorporating game design
elements in teaching space science.
Example: Scavenger Hunt, Space
Maze, Gross Motor Moon Phases,
Space Exploration Crossword,
Space Word Search, Space Quiz
 Space Place Art
create a station that helps pupils
learn about space through art.
Example: Art Challenge, Outer
Space Painting, Space Story
Challenge using puppets,
creating constellations from
different materials and others.