Constellations powerpoint

Pre/Diagnostics Test Star Color A Red B Yellow C White D Blue 1. Which star is the hottest?

2. Which star is very similar to our Sun? 1

3. How do stars appear to move in the night sky?

A. From East to West B. From North to South C. From West to East D. From South to North 4. Stars appear to move in the sky because A. The Earth is rotating on its axis.

B. The Universe is expanding.

C. The night sky is rotating.

D. New galaxies are formed.

5. If you are located at the North Pole, where will you see the Polaris?

A. Overhead B. Just above the horizon C. Around 45° from the horizon D. Polaris will not be seen in the North Pole.

6. Which constellation is prominently seen in the sky during summer?

A. Orion B. Pegasus C. Hercules D. Virgo

Characteristics of our stars approximately 400 billion stars in our galaxy, and there are about 170 billion galaxies. A person can see only about 3,000 stars on the average. ď Ž These stars differ in many ways. We see stars of different sizes, brightness, and color ď Ž

Star color ranges from red to blue. The color of the star indicates its surface temperature.

Star Color Surface Temp(deg Cel) Sun Yellow 5,700 Proxima Centuari Red 2,300 Epsilon Iridani Orange 4,600 Vega White 9,900 Sirius White 10,000 Alnilam Blue 27,000

The brightness of a star as seen from the Earth depends on two factors1. distance 2. actual brightness (or absolute brightness) of the star. *The star’s brightness as seen from Earth is its apparent brightness, depends on how far away a star is from the Earth.

ď Ž

Compared to the Sun, Sirius is about 27 times as powerful as the Sun, but Rigel has the power of many thousands of Suns. In terms of distance from the Earth, Rigel is almost 100 times farther away than Sirius. In terms of apparent brightness, Sirius is about twice as bright as Rigel. Sirius looks very bright when viewed from Earth because it is closer to Earth.

TO BE DONE AT HOME, DUE FRIDAY Activity 1.Apparent Movement of the Stars through the Night Objectives: Describe the apparent motion of stars at night.

Procedure: 1. On a clear night sky, look at the stars from 7 pm to 11 pm.

2. Focus on one or two constellations like the Auriga and Orion which are best seen in the month of December.

3. Look at the stars clearly every hour of the night, from 7 pm to 11 pm.

Q1. Compare the position of the stars in the sky. What do you notice?

Q2. Are the stars visible at 7 pm still visible at 11 pm in their “original position�? Why is this so?

Q3. How do the stars move? Describe the movement of the stars in the night sky.

Q4. How is the motion of stars similar to the motion of the Sun?

ď Ž

By observing Sun’s movement and position in the sky, we can tell what time of the day it is. When it seems to rise in the east, it is morning. When it is above us, it is noon. When it seems to move towards the west, it is afternoon. At night, stars are used to tell the time.

Just like the Sun, stars also seem to move from East to West

Introduction to Constellations

Introduction to Constellations Backyard Astronomy

Star Maps are also called planespheres.

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CONSTELLATIONS -imaginary group of stars -

traced back to early Babylonians and Greek civilizations For example, the Greeks called the large constellation Orion (hunter),prominent in the night sky all over the world during winter. Early Filipinos visualized the same group of stars as Balatik, a trap used in hunting wild pigs.

Christian Filipinos named the three stars (Orion’s belt) Tatlong Maria or Tres Marias.

Finding Polaris and Why Polaris (or the North Star) is where you want to start.

Because Polaris is aligned with the Earth’s axis of rotation, it remains fixed, with all the other planets and stars appearing to move around it. It is the one star that remains fixed at all times.

Polaris and the Star Trail over Mt. Pulag

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ď Ž Polaris

and the star trail are seen.

Star trail is a type of photograph that utilizes long-exposure times to capture the apparent motion of stars in the night sky due to the rotation of the Earth.

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ď Ž

In Metro Manila, when you face North, Polaris, which is 11.3o from the horizon, is seen at around 15° due to atmospheric refraction. In some parts of the country (i.e. Southern Philippines), it would be very difficult to locate Polaris since starlights near the horizon are washed out by lights lit by men, and /or obstructed by man-made or topographical structures and/or trees.

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To locate the Polaris, face North and locate the Big Dipper. Two stars (Merak and Dubhe) in the Big Dipper are called pointer stars because they seem to point to Polaris.

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Another Way to Find Polaris There is another way to find Polaris. Find the Big Dipper, the two stars that form the front of the cup of the dipper define a line pointing to Polaris.

The Big Dipper

ď Ž

Figure 5a. March Night Sky (9 p.m.)

Figure 5a. March Night Sky (9 p.m.)

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Figure 5b. June Night Sky (9 p.m.)

Figure 5c. September Night Sky (9 p.m.)

Figure 5d. December Night Sky (9 p.m.)

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How Early People Used the Constellations Before the calendars, people had no way of determining when to sow or harvest except by looking at these patterns in the sky. Ancient people developed a way to remember the patterns by giving these patterns names and stories. For example, in the northern hemisphere, the constellation Orion indicates the coming of cold season. Gemini is seen in the Philippines during the months of April and May. Farmers interpreted the appearance of Gemini as the end of planting

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Table 2: Stars and Constellations Used by Matigsalug Manobo of Bukidnon Local Name

Month of Appearance

Related Activity Western Equivalent

Baha

December to February

Clearing of forest

Taurus

Pandarawa

January

Start of planning

Pleiades

Balatik

February

Start of planting

Orions’s Belt

Gibbang

April and May

End of planting season; Gemini

Malara

May

Stop planting

Canis Minor

Lepu

Late May

time to clean or clear t

Aquila

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Other Uses Another use of constellations was in navigation. The Polaris is widely used in navigation because it does not change its position at any time of the night or year. Also, one can figure out his/her latitude just by looking at how high Polaris appears in the night sky. This allowed sailors to find their way as they sail across the seas.

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A Few Constellations...

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Ursa Minor Once you’ve located Polaris, you’re ready to identify your first constellation. Polaris is the last star located in the handle of the asterism, the Little Dipper.

The name of the constellation that contains the Little Dipper is Ursa Minor or Little Bear.

Ursa Minor There are several mythological stories behind these famous constellations. In Greek myth, Zeus was having an affair with the lovely Callisto.

When his wife, Hera, found out she changed Callisto into a bear. Zeus put the bear in the sky along with the Little Bear, which is Callisto's son, Arcas.

Ursa Minor

Ursa Major Ursa Major is probably the most famous constellation, with the exception of Orion. Also known as the Great Bear, it has a companion called Ursa Minor, or Little Bear. The body and tail of the bear make up what is known as the Big Dipper.

Ursa Major

Draco, the Dragon.

The easiest way to spot Draco is by finding his head. It consists of four stars in a trapezoid, burning brightly just north of Hercules. From there, the tail slithers through the sky, eventually ending between the Big and Little Dippers. It can be difficult to trace Draco in the night sky. From the head, follow the body north towards Cepheus. It suddenly shifts south and west, ending up between the two dippers. The end of the constellation is held by Thuban, which was the pole star over 4,000 years ago.

Draco

Orion’s Belt

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Signs of the Zodiac Common Constellations

Aquarius: The Water Bearer In Greek mythology Aquarius was Ganymede, "cup-bearer to the gods". Alpha Aquarii ("Sadalmelik") and beta Aquarii ("Sadalsuud") are twin supergiants with nearly identical names. The names mean, respectively, "The Lucky One of the King" and "The Luckiest of the Lucky". Gamma Aquarii shares in the good fortune: "Sadachbia": "The Lucky Star of Hidden Things�

Aquarius: The Water Bearer

Aries: the Ram Aries, "The Ram", is an ancient constellation which was of considerable importance since the sun passed through it at the vernal equinox. ď Ž This point has now moved into Pisces, but the vernal equinox is still known as the First Point of Aries. In another six hundred years the point will have moved

Aries: the Ram

Cancer The Crab The name comes from the Latin; cancer means crab.

The crab in question is the one sent by Hydra to attack Heracles. It was only a bit part, but one which secured its immortality.

Cancer

Gemini The Twins Gemini, the Twins, are really only halfbrothers. They share the same mother (Leda) but have different fathers. Castor's father was a king of Sparta, Tyndareus who would be chased from his throne but later rescued by Heracles (who nevertheless wound up killing him). The father of Pollux was none other than Zeus, or Jupiter. Zeus visited Leda on her wedding night in the guise of a swan. Thus the twins would be born. (In fact two twins came from this double union, but let's not complicate the matter even more...)

Gemini

Leo: The Lion The first on the list of Heracles' labors was the task of killing the Nemean Lion, a giant beast that roamed the hills and the streets of the Peloponnesian villages, devouring whomever it met.

Heracles' arrows harmlessly bounced off the lion; his sword bent in two; his wooden club smashed to pieces.

So Heracles wrestled with the beast, finally choking it to death. He then wrapped the lion's pelt about him.

Leo

Libra: The Scales Libra means "The Scales" or "Balance", the sun passed through this constellation at the autumnal equinox (21 September).

At the two equinoxes (Spring and Autumn) the hours of daylight and darkness are equal. As a symbol for equality, the constellation came to represent Justice in several middle Eastern cultures. However, the Greeks had a different perspective; at one time Scorpius, which lies just to the east, was much larger, and the stars that make up Libra were then known as the Claws of the Scorpion.

Libra

Pisces: The Fish Pisces is an ancient constellation derived, some say, from the story of the terrible Greek god Typhon. (means "cyclone".)

Pisces

Sagittarius It was the Romans who named the constellation Sagittarius ("sagitta" is Latin for `arrow'), although several stars carry Arabic names which identify just which portion of the constellation they represent.

Sagittarius has a muddled history. In ancient times the asterism of three bright stars in a curved line was seen as a bow to some, leading both Greek and Roman writers to confuse the constellation with Centaurus.

Sagittarius

Scorpius: The Scorpion Gaia may have sent the scorpion to kill the mighty hunter, as he had vowed to rid the earth of all wild animals. Or Apollo might have told Gaia of Orion's boast, fearful that Orion had designs on Apollo's sister Artemis. In any case it was Gaia who sent the scorpion to kill Orion. Later the animal would chase Orion across the heavens, but it could never catch him, for the scorpion was so placed that it would rise in the east only after Orion had safely disappeared over the western horizon.

Scorpius

Taurus: The Bull Is Taurus attacking Orion, the Hunter, or are the Horns of the Bull the real story? The horn was a symbol of fertility and bountiful riches in many cultures for thousands of years, and it is probably the case here, for the constellation would have announced the Vernal Equinox at around 4000 BC.

Taurus

Virgo: The Virgin Virgo is the second largest constellation (after Hydra). The Sun passes through Virgo in midSeptember, and is therefore the constellation that announces the harvest. Virgo is often represented as a "maiden" (as its name indicates). In antiquity, she may have been Isis, the Egyptian protectress of the living and the dead and the principal mother goddess.

Virgo

Characteristics of our stars approximately 400 billion stars in our galaxy, and there are about 170 billion galaxies. A person can see only about 3,000 stars on the average. ď Ž These stars differ in many ways. We see stars of different sizes, brightness, and color ď Ž

Star color ranges from red to blue. The color of the star indicates its surface temperature.

Star Color Surface Temp(deg Cel) Sun Yellow 5,700 Proxima Centuari Red 2,300 Epsilon Iridani Orange 4,600 Vega White 9,900 Sirius White 10,000 Alnilam Blue 27,000