This document provides information about stars and constellations. It discusses what stars are made of and how they produce energy. It also notes that there are over 100 billion galaxies in the universe, each containing over 100 billion stars. The document then describes different types of stars like dwarfs, giants, and supergiants. It also explains luminosities, magnitudes, and various notable stars like Betelgeuse, Sirius, and Deneb. Finally, it summarizes several zodiac constellations like Taurus, Gemini, and Scorpius.

1. STARS AND
CONSTELLATIONS
PRESENTED BY: G11-20
JOHN NINO GARCIA
RAIN ANGELA CRUZ
PRESENTED TO:
MRS. TADEO

2.  Stars are cosmic energy engines that produce heat,
light, ultraviolet rays, x-rays, and other forms of
radiation. They are composed largely of gas and
plasma, a superheated state of matter composed of
subatomic particles.
 No one knows how many stars exist, but the number
would be staggering. Our universe likely contains
more than 100 billion galaxies, and each of those
galaxies may have more than 100 billion stars.

3.  Some stars have always stood out from the rest.
Their brightness is a factor of how much energy
they put out–known as luminosity–and how far
away from Earth they are.
 Stars in the heavens may also appear to be
different colors because their temperatures are not
all the same. Hot stars are white or blue, whereas
cooler stars appear to have orange or red hues.
 Stars may occur in many sizes, which are classified
in a range from dwarfs to supergiants. Supergiants
may have radii a thousand times larger than that of
our own sun.

4. These stars' energy comes from nuclear fusion, as they convert Hydrogen to Helium. Most
stars (about 90%) are Main Sequence Stars. For these stars, the hotter they are, the brighter
they are. The sun is a typical Main Sequence star.
DWARF STARS
Dwarf stars are relatively
small stars, up to 20 times
larger than our sun and up to
20,000 times brighter. Our
sun is a dwarf star.
YELLOW DWARF
Yellow dwarfs are small, main
sequence stars. The Sun is a
yellow dwarf.

5. RED DWARF
A red dwarf is a small, cool, very faint,
main sequence star whose surface
temperature is under about 4,000 K.
Red dwarfs are the most common
type of star. Proxima Centauri is a red
dwarf.

6.  Stars are born in nebulae. Huge clouds of
dust and gas collapse under gravitational
forces, forming protostars. These young
stars undergo further collapse, forming main
sequence stars.
 Stars expand as they grow old. As the core
runs out of hydrogen and then helium, the
core contacts and the outer layers expand,
cool, and become less bright. This is a red
giant or a red super giant (depending on the
initial mass of the star). It will eventually
collapse and explode. Its fate is determined
by the original mass of the star; it will
become either a black dwarf, neutron star,
or black hole.

7. RED GIANT
A red giant is a relatively old star whose diameter is about
100 times bigger than it was originally, and had become
cooler (the surface temperature is under 6,500 K). They are
frequently orange in color. Betelgeuse is a red giant. It is
about 20 times as massive as the Sun about 14,000 times
brighter than the Sun, and about 600 light-years from Earth.
BLUE GIANT
A blue giant is a huge,
very hot, blue star. It
is a post-main
sequence star that
burns helium.
SUPERGIANT
A supergiant is the largest
known type of star; some are
almost as large as our
entire solar
system. Betelgeuse and Rigel a
re supergiants. These stars are
rare. When supergiants die
they supernova and
become black holes.

8. WHITE DWARF
A white dwarf is a small, very
dense, hot star that is made mostly
of carbon. These faint stars are
what remains after a red giant
star loses its outer layers. Their
nuclear cores are depleted. They
are about the size of the Earth (but
tremendously heavier)! They will
eventually lose their heat and
become a cold, dark black dwarf.
Our sun will someday turn into a
white dwarf and then a black dwarf.
The companion of Sirius is a white
dwarf.
BROWN DWARF
A brown dwarf is a "star"
whose mass is too small to
have nuclear fusion occur at
its core (the temperature and
pressure at its core are
insufficient for fusion). A brown
dwarf is not very luminous. It is
usually regarded as having a
mass between 1028 kg and 84
x 1028.

9. NEUTRON STAR
A neutron star is a very small,
super-dense star which is
composed mostly of tightly-
packed neutrons. It has a thin
atmosphere of hydrogen. It has a
diameter of about 5-10 miles (5-
16 km) and a density of roughly
10 15 gm/cm3.
PULSAR
A pulsar is a rapidly
spinning neutron star that
emits energy in pulses.

10. LUMINOSITY
Luminosity is the total brightness of a star or galaxy.
ABSOLUTE AND APPARENT MAGNITUDE
Apparent magnitude is a measure of the brightness of a celestial object as seen from
Earth. The lower the number, the brighter the object. Negative numbers indicate extreme
brightness. The full moon has an apparent magnitude of -12.6; the sun's is -26.8. We
can see objects up to 6th magnitude without a telescope. Apparent magnitude is
abbreviated m. This system of rating the brightness of celestial objects was developed
by the Greek astronomer Hipparchus in 120 B.C.
Absolute magnitude is a measure of the inherent brightness of a celestial object. This
scale is defined as the apparent magnitude a star would have if it were seen from a
distance of 32.6 light-years (10 parsecs). The lower the number, the brighter the object.
Negative numbers indicate extreme brightness.

11. Rank Star Absolute Magnitude Apparent Magnitude Distance from Earth
(light-years)
. The Sun +4.8 -26.72 .
1 Sirius (in Canis Major) +1.4 -1.46 8.6
2 Canopus (in Carina) -2.5 -0.72 74
3
Rigel Kentaurus (Alpha Centauri) (in
Centaurus)
+4.4 -0.27 4.3
4 Arcturus (in Boötes) +0.2 -0.04 34
5 Vega (in Lyra) +0.6 0.03 25
6 Capella (in Auriga) +0.4 +0.08 41
7 Rigel (in Orion) -8.1 +0.12 900
8 Procyon (in Canis Minor) 2.8 +0.38 11
9 Archenar (in Eridanus) -1.3 +0.46 75
10 Betelgeuse (in Orion) -7.2 +0.50 1,500
11 Hadar (in Centaurus) -4.3 +0.61 300
12 Altair (in Aquila) +2.3 +0.77 17
13 Acrux (in Crux) -3.8 +0.79 270
14 Aldebaran (in Taurus) -0.2 +0.85 65
15 Antares (in Scorpius) -4.5 +0.96 400
... ... ... ... ...
20 Deneb (in Cygnus) -7.2 +1.25 1,500
-- Proxima Centauri (in Centaurus) +15.5 +11.05 (var.) 4.3

12. ANTARES
(Alpha Scorpii) Antares (meaning "Rival of
Mars") is the brightest star in Scorpius, one of
the constellation in the zodiac. Antares is a
M1.5Iab variable red supergiant star that is
about 520 light-years from Earth and is about
230 times as big as the Sun. This incredibly
massive, old, low-temperature (3500 K) star is
the 15th brightest star in the sky; it has a visual
(apparent) magnitude of +0.96 (var.) and an
absolute magnitude of -5.2.
ARCTURUS
(Alpha Boötis) Arcturus is the brightest star in
the constellation Boötes (the herdsman). It is a red
giant (spectral type K1.5IIIp) that is the fourth
brightest star in the sky. Arcturus is 34 light-years
from Earth. It has an apparent magnitude of -0.04
and an absolute magnitude of 0.2.

13. BETELGEUSE
(pronounced "beetle juice") Betelgeuse (alpha
Orionis) is the second-brightest star in
the constellation Orion and one of the brightest stars
in the sky. It is a supergiant star, reddish in color, and
over 600 million miles in diameter (almost 1,000 times
bigger than the Sun but cooler than the Sun). If
Betelgeuse were at the center of our Solar System, it
would extend beyond the orbit of Jupiter. It is
520 light-years from Earth. It is a variable star, varying
in magnitude from 0.3 to 1.2 over a period of about 7
years, averaging about 0.70. It is the only star (other
than our sun) for which we have surface images.
DENEB
Deneb (which means "tail" in Arabic) is the brightest
star in the constellation Cygnus (the swan); Deneb is
also referred to as alpha Cygni, and is the tail of the
swan. This young, bright, white supergiant star is
about 1,500 light years away. Deneb is about 60,000
times more luminous than the sun!

14. POLARIS
Polaris (alpha UMi) is the current pole star for the Northern
Hemisphere; it is 1 degree from the exact Northern
celestial pole. In 1780, Sir William Herschel discovered
that Polaris was a double star with a faint companion star.
Polaris is a blue-green Cepheid variable star (its size
brightness changes periodically, with period of 3.969778
days; it varyies between mag 1.92 and 2.07). Polaris has a
relatively dim companion star (9th magnitude). Polaris'
distance from Earth has been estimated to be from 360 to
820 light years. At its brightest, Polairs is about 6,000 to
10,000 times brighter than our Sun. It is the larger star at
the end of the handle of the Little Dipper (Ursa Minor).
Polaris is also called the Lodestar or the Cynosure.
ORION
Orion, also known as "The Hunter," is a constellation in
the zodiac. The brightest stars in Orion
are Rigel, Betelgeuse, and Bellatrix. The Horsehead
Nebula and the nebulae M42 and M43 are also in this
constellation.

15. RIGEL
Rigel (beta Orionis) is the brightest star in
the constellation Orion and one of the brightest
stars in the sky. It is a blue (very hot) supergiant,
over 60 million miles in diameter (almost 100 times
bigger than the sun). It is more than 50,000 times
more luminous than the Sun. It has an absolute
magnitude of -7.1 and an apparent magnitude of
+0.12. It is over 900 light-years from Earth.
SIRIUS
Sirius (meaning "scorching" in Greek), also known
as the dog star, is the brightest star in the sky
(except for the sun). It is in the constellation Canis
Major (The Great Dog). Sirius is a main sequence
star that is about 70 times more luminous than the
sun. It is about 8.6 light-years from Earth. It has
an apparent magnitude of -1.46 and an absolute
magnitude of +1.4. Sirius has a companion star
(called the Pup), which is a white dwarf.

16. NORTH STAR
The north star is a star that is located almost due
north and is useful for navigation. Polaris is
currently the pole star of the Northern
Hemisphere.
VEGA
Vega (Alpha Lyrae) is a very bright star in the
constellation Lyra. It is also known as the Harp
Star and Fidis. Vega is the 5th brightest star in
the sky and is pale blue. It is about 25 light
years from Earth. Its spectral type is A0Va. A
disk of dust surrounds Vega, from which
planets might form. Vega, together
with Deneb and Altair form the Summer
Triangle.

17. CONSTELLATION
• group of stars that, when seen from Earth,
form a pattern. The stars in the sky are
divided into 88 constellations.
ZODIAC
CONSTELLATION
http://www.enchantedlearning.com/subjec
ts/astronomy/stars/constellations.shtml
https://image.shutterstock.com/z/stock-
vector-zodiac-with-constellations-and-
zodiac-signs-95268319.jpg

18. ARIES Mar. 21 - April 19
Located in the northern
hemisphere. Its name means “the
ram” in Latin.
Autumn constellation, and can be
best viewed in the night sky during
the month of November.
Aries is the 39th largest
constellation in the sky, occupying
441 square degrees.
http://www.constellation-
guide.com/constellation-
list/aries-constellation/

19. TAURUS April 20 - May 20
• Taurus constellation lies in the
northern sky. Its name means “bull”
in Latin.
• In Greek mythology, the
constellation is associated with
Zeus.
• Autumn constellation, and can be
best viewed in the night sky during
the month of December.
• Taurus is the 17th largest
constellation in the sky, occupying
an area of 797 square degrees.
http://www.space.com/17101-taurus-
constellation.html
http://www.constellation-
guide.com/constellation-
list/taurus-constellation/

20. GEMINI May 21 - June 21
• Gemini constellation is
located in the northern
hemisphere of the sky. Its
name means “the twins” in
Latin.
• Gemini is the 30th largest constellation in the sky,
occupying an area of 514 square degrees.
• Winter constellation, and can be best viewed in the night
sky during the month of January.
http://www.constellation-
guide.com/constellat ion-list/gemini-
constellation/

21. CANCER June 22 - July 22
• Cancer constellation is located in
the northern sky. Its name means
“the crab” in Latin.
• Cancer is the faintest of the 12
zodiac constellations
• Cancer is the 31st largest
constellation in the sky, occupying
an area of 506 square degrees.
• Winter Constellation, and can be
best viewed in the night sky during
the month of February.
http://www.constellation-
guide.com/constellation-list/cancer-
constellation/

22. LEO July 23 - Aug. 22
• Leo constellation lies in the
northern sky. It is one of the zodiac
constellations and one of the
largest constellations in the sky.
• Leo represents the lion and is
usually associated with the
Nemean lion in Greek mythology.
• Leo is the 12th largest constellation
in size, occupying an area of 947
square degrees.
• Winter constellation, and can be
best viewed in the night during the
month of March. http://www.constellation-
guide.com/constellation-list/leo-
constellation/

23. VIRGO Aug. 23 - Sept. 22
• Virgo constellation lies in the southern
sky. Its name means “virgin” in Latin.
• It contains Spica, one of the brightest
stars in the night sky.
• Virgo is the second largest
constellation in the sky, occupying an
area of 1294 square degrees.
• Spring constellation, and can be best
viewed during the month of April.
http://www.constellation-
guide.com/constellation-list/virgo-
constellation/

24. LIBRA Sept. 23 - Oct. 23
• Libra constellation lies in the
southern sky.
• The constellation’s name means
“the weighing scales” in Latin.
• Libra is the only zodiac
constellation that represents an
object, not an animal.
• Libra is the 29th constellation in
size, occupying an area of 538
square degrees.
• Spring constellation, and can
be best viewed in the night sky
during the month of May.http://www.constellation-
guide.com/constellation-
list/libra-constellation/

25. SCORPIUS Oct. 24 - Nov. 21
• Scorpius constellation lies in the southern sky.
• Scorpius pre-dates the Greeks, and is one of the oldest
constellations known.
• Scorpius is the 33rd constellation in size, occupying an
area of 497 square degrees.
• Spring constellation, and can be best viewed in the night
sky during the month of June.
http://www.constellation-
guide.com/constellation-
list/scorpius-constellation/

26. SAGITTARIUS Nov. 22 - Dec. 21
• Sagittarius constellation lies in the southern
sky.
• It represents the archer.
• Sagittarius is usually depicted as a centaur
holding a bow and arrow.
• Sagittarius is one of the largest southern
constellations.
• It is easy to find because it lies on the Milky
Way and its brightest stars form an
asterism known as the Teapot.
• Sagittarius is the 15th largest constellation
in the sky. It occupies an area of 867
square degrees.
• Summer constellation, and can be best
viewed in the night sky during the
month July. http://www.constellation-
guide.com/constellation-
list/sagittarius-constellation/

27. CAPRICORNUS Dec. 22 - Jan. 19
• Capricornus constellation is
located in the southern sky.
• Its name means “the goat”
in Latin.
• It is one of the faintest
constellations in the sky.
• Capricornus is the 40th
biggest constellation in the
sky, occupying an area of
414 square degrees.
 Summer constellation with an
astronomical name of Capricornus, and
can be best viewed in the night sky during
the month of August.
http://www.constellation-
guide.com/constellation-
list/capricornus-constellation/

28. AQUARIUS Jan. 20 - Feb. 18
• Aquarius lies in the region of the sky
which is sometimes referred to as the
Sea.
• The constellation’s name means “the
water-bearer” (or “cup-bearer”) in Latin.
• Aquarius is the 10th largest
constellation in the sky, occupying an
area of 980 square degrees.
• Summer constellation, and can be best
viewed in the night sky during the
month of September.
http://www.constellation-
guide.com/constellation-
list/aquarius-constellation/

29. PISCES Feb. 19 - Mar. 20
• Pisces constellation lies in the
northern sky.
• Its name means “the fish” (plural) in
Latin.
• Pisces lies between Aries
constellation to the east
and Aquarius to the west.
• Pisces is the 14th constellation in
size, occupying an area of 889 square
degrees.
• Autumn constellation, and can be
best viewed in the night sky during the
month of October.
http://www.constellation-
guide.com/constellation-list/pisces-
constellation/

30. References:
 http://www.nationalgeographic.com/science/space/universe/stars/
 http://www.enchantedlearning.com/subjects/astronomy/stars/
 http://www.enchantedlearning.com/subjects/astronomy/stars/lifecycle/
 http://www.enchantedlearning.com/subjects/astronomy/stars/startype
s.shtml
 http://www.enchantedlearning.com/subjects/astronomy/stars/bright.sh
tml
 http://www.enchantedlearning.com/subjects/astronomy/stars/majorsta
rs.shtml