1. LESSON 2. Salient Features of the Sun
Sun- is the largest body in our solar
system.
- it is the nearest star to our
planet.
- it is only one of the many
billions of stars in the galaxy and a
typical main-sequence star.
2. Table 14.1: Data of the Sun
Distance
93 million miles
Diameter
864,400 miles
Volume
1,250,000 times greater than te earth
Mass
2 x 10 kg
Density
1.41 g/cm
Inclination
7 degrees - 10 degrees
Surface Temperature
6,000 degrees celsius
Equatorial
15,000,000 degrees celsius
Rotation Polar
Once every 33 days
Equatorial
Once every 25 days
Life span
11 billion years
Solar constant
1.94 calories/cm/min
Age
4.6 billion years
Type
Yellow dwarf
3. The Sun's Atmosphere
- the most familiar sight as we
observed the sun at early dawn or
during sunset.
- it consists of four layers:
photosphere, chromosphere,
corona, and reversing layers.
4. Photosphere
- is the light sphere and the main body of
the sun.
- this layer is 150 miles thick and with a
temperature of 6,000 degrees celsius.
- this layer of the sun is characterized
with various disturbances: granules,
faculae, and sunspots.
5.
6. 1. Granules- are bubbles of hot gases
that appear in cycles of bright and dark
spots reaching up to 621 miles.
2. Faculae- (small torches) are small, but
sharp eruptions which last for about 15
minutes to one hour.
3. Sunspots- are darker, cooler areas in
the atmosphere. They range size from
800 to 80,000 km in diameter.
7. Chromosphere
- is the color sphere.
- it extends from 5,000 to 8,000 miles
thick.
- when observed during total solar
eclipse or with the use of an
instrument.
- it appears in a rose pink in color.
- it also characterized with disturbances
also referred to as "storms".
8.
9. • Solar Flares- are gigantic eruptions that
bombard the earth electromagnetic
waves (X-rays, gamma rays, ultraviolet
rays, infrared rays) and particles.
• they occur near sunspots and may
spread up to 100,000 miles or more in
space.
• The Electromagnetic waves reach Earth
eight minutes after the initial burst.
10.
11. • These waves cause interference in
radio and telecommunication
operations.
• The particles are the protons and
electrons that are released from
hydrogen atoms that are shattered to
pieces.
- they are driven by the earth's
magnetic field to the southern and
northern hemisphere.
12. Aurora- the colliding with the particles of
our atmosphere, causing the formation
of brilliant displays of light.
- it is also purely electrical charges
that look like neon lights in the sky that
may last for days or weeks.
13.
14. Prominences- are billowing arches of
rose-colored flame, which also occur
near sunspots.
- they may go up to about
500,000 to one million miles in space.
15.
16. Corona- is the outer most layer of the
sun's atmosphere.
- this layer is also visible only
during solar eclipse.
- its shape varies with the elevenyear period of sunspots.
- its formed by the vapors emitted
by the bubbling gases in the
photosphere.
- the temperature of corona
ranges from 1 to 2 million degrees
celsius.
21. Lesson 3: Characteristics of the Eight
Planets of the Solar System
• Eight planets revolve around the sun
with remarkable precision.
• Speed, Eccentricity and Distance from
the sun characterize the orbits of the
planets.
• Possibility of their crossing, allowing
collision of planets and satellites to
occur
- these are the numbers and variety of
orbits in the solar system suggest this
possibility.
22. • Mercury- has a small magnetic field.
• Venus and Mars- have very weak
magnetic fields.
• Earth- has a very significant magnetic
field.
• Jupiter- has a very large and strong
magnetic field.
• Warning process in the atmosphere of
Jupiter, Saturn, Uranus, and Neptune- is
much similar to that of the earth, but
their absorbing materials are different.
23. • Earth- is warmed by the heat
developed in the absorption of
ultraviolet rays by the ozone layer in
the atmosphere while the outer
planets are warmed by the heat
developed by the absorption of solar
radiation of methane and the smog of
some particles.
• Jupiter, Saturn, and Neptune- are
found to be emitting more heat than
they receive from the sun
24. • Planets- are grouped according to
size.
• Terrestrial planets- are small and
they have high densities due to
their bodies made up of rocks and
heavy elements.
• Mercury, Venus, Earth, And Marsare considered terrestrial planets.
• Jovian planets- are larger and
massive and they have low
densities and have dense
25. Characteristics of the Eight Planets of the Solar System
Number
of
Satellite
Distance from
the sun
Inclination
Rotation
MERCURY
58 million km
7 degrees
14 minutes
About 58.7
days
88 days
0
Heavily
cratered
planet
VENUS
67 million miles
3 degrees
39 minutes
243 days
225 days
o
Veiled planet
EARTH
93 million miles
23 degrees
30 minutes
24 hours
365 days
1
Blue planet
MARS
141,700,000 0
miles
25 degrees
1.37
1.88 years
2
Red planet
3 degrees
10 hours
19
Largest planet
23
Pale
yellow,ringed
planet
5
Bluish-green
with righs
2
Planet with a
clear
atmosphere
Planet
JUPITER
Revolution
SATURN
URANUS
NEPTUNE
1.79 billion miles
98 degrees
30 degrees
17.24 hours
14 hours
84 years
165 years
Description
26. Lesson 4. Asteroids, Comets, and
Meteors
• Asteroids- are small chunks of
irregularly shaped objects that occupy
the 350 million miles space between
Mars and Jupiter.
• They orbit the sun in a belt following
the same direction as those of the
planets.
- the asteroid belt range in size.
If all the asteroids were put together
they would form a body no more than
1,500 km in diameter.
27. • Their number is estimated to
be about 30,000 but only about
7,000 have been identified..
• They vary in size, shape,
color, and composition.
• A German astronomer Johan Bode
accidentically discovered the
existence of these miniature
planets in 1800.
28. • Ceres- is the largest asteroids, 940
km in diameter.
Giuseppe Piazzi discovered it
on January 1, 1801. Ceres was named
after
the
Roman
goddess
of
agriculture and also known as the
protecting goddess of Sicily.
Pallas- is the second largest, 540 km
in diameter.
Vesta- which is 510 km in diameter.
About
500
other
asteroids
are
between 50 to 100 km in diameter
and the rest are smaller than 50 km.
29. 3 types of asteroids as their color and
composition
• C-type asteroids- are very dark
and carbonaceous. There are
75% of known asteroids.
• S-type asteroids- are rusty red in
color and they are composed of
iron and magnesium silicate.
• M-type asteroids- are rich with
metallic substances.
30. 3 types of asteroids according to
position:
1.Athensis
the
first
type
of
asteroids.They lie near the orbit of
Mars. Some examples are Ceres, Pallas,
Juno, and Vesta.
2.Apollosis
the
second
type
of
asteroids. They lie near Jupiter and
they have highly elliptical orbits.
Eros,
Geographos,
and
Icarus
are
examples. These asteroids constantly
cross the earth's orbit.
Icarus reached the earth about 6
million km.
31. Geographos- reached the earth at a
distance of about 9 km.
Eros- at about 485,000 miles.
3.Trojans- are the third type. They
lie within the main asteroid belt
and they circle the sun for 12
years.
Examples are Hector, Diomedes,
Agamemnon, and Petrocius.
32. COMETS
it is known since ancient times.
they were once associated to bad
omens and disaster.
Oort Cloud- comet originated
from a dense shell of material
surrounding the outer edge of
the solar system.
Jan Oort- Dutch Astronomer.
Comets- orbits are big and
33. • As they revolved around the
sun some can reach the outer
edge of the solar system and
then
back,
moving
closer
towards the sun.
• As they get closer to the sun,
they become very bright and
start forming a tail.
34. 3 Basic Parts of Comets
1. NUCLEUS- which is believed to be
solid and composed of frozen gases,
water vapor, and dust particles.
2. COMA- a cloudlike structure that
surrounds the nucleus which is
composed of gas and small bits of
rocks and dust.
3. TAIL- that is composed of gas or
dust particles or both. Comets may
have one or several tails.
35. • When the comet is away from the
sun, it has no tail.
• Comets appear in the sky from time
to time.
• Some comets return on a cycle every
few years.
2 Groups of Comets according to their
order of appearance:
1. Short-period comets- have orbits
that take less than 200 years.
2. Long-period comets- have orbits
that take more than 200 years.
36. • Haley's comet appears every 76 years
.
• Edmund Haley- predicted its
appearance in 1910.
• The last time it reappeared was in
1986 and it is predicted to reappear
again in the year 2062.
• Kuiper Belt Objects(KBO)
- this is the name given to many
small bodies found orbiting the sun
from beyond Neptune and Pluto.
37. • Oort Cloud- is a theoretical, spherical
gathering of rocks at the outer edge
of the solar system.
• Meteors- are the bright streak of
light that dart the night sky which
are referred to as "shooting star".
• In reality meteors are "space debris"
or stray pieces of stony or metallic
rocks that pass through the earth's
atmosphere.
38. • Meteors travel in great speed that sometimes
exceeds 100,000 miles per hour.
• Friction with the earth's atmosphere caused
them to glow and vaporize completely in
space.
• Meteorites- the large ones reach the earth's
surface.
• Meteor shower- is a celestial event in which
a number of meteors are observed to radiate
from one point in the night sky.
- it is a regular sight sometime in the midmonth of
August because in this month Earth crosses the
path of comets and meteors are seen in the
Esrth's atmosphere.
39. Summary in lesson 2;
• The sun is the largest celestial body in the solar
system.It has a various characteristics.
• The sun's atmosphere is the most prominent
layer that we see in the sky. The solar
atmosphere
consists
of
four
layers:
Photosphere, Chromosphere, Reversing layer,
and Corona.
• The
photosphere
is
characterized
by
disturbances. The most familiar to us are the
sunspots.
• The chromosphere is likewise characterized by
disturbances. The solar flares are disturbances
that have profound effect on Earth's
atmosphere.
40. Summary in lesson 3:
• The planets are classified according
to size. The terrestrial planets are
Mercury, Venus, Earth, and Mars,
while Jovian Planets are Jupiter,
Saturn, Neptune, and Uranus.
• The eight planets differ in terms of
distance from the sun, rotation,
revolution,inclination,and number of
satellites.
41. Summary in lesson 4:
• Impact of asteroids larger than 500 meters on
the earth's surface can cause global
devastation. But this is an extremely rare
phenomenon.
• Astronomers consider all three celestial
objects as space debris.
• Comets have large and elliptical orbits and
return on a predictable cycle of few years.
• Asteroids are chunks of irregularly shaped
objects that occupy the space between Mars
and Jupiter.
• Meteors are stray pieces of objects that
appear in the night sky as shooting stars.
