Astronomy Grade 8

Skylab

1973 U.S. space station

What is Earth's period of daytime?

24 hours

How long does it take the moon to cycle through its phases?

29.5 days

What is the diameter of the moon?

3,476 km diameter; 1/4 of Earth's (about the distance accross the United States

What is the length of time it takes for the Earth to orbit the sun once?

365 1/4

What is a satellite?

Any natural or manmade object that revolves around another object in space

Winter Solstice

December 21; First day of winter. shortest day of the year

What causes day and night on earth?

Earth's rotation on its axis

rotation

Earth's spinning on its axis

Who created the first calanders?

Egyptian astronomers

What phase must the moon be in for a lunar eclipse?

Full moon only

Who invented the telescope?

Galileo 1609

Why do you see a certain phase of the moon?

It depends on how much of the sunlit side of the moon faces Earth

Why is the moon's "day" and "year" the same length?

It take the moon 27.3 days to rotate once and 27.3 days to revolve around the Earth

Why do we only see one side of the moon?

It takes the same time to rotate as revolve

When did man land on the moon?

July 20, 1969 - Neil Armstrong

Summer Solstice

June 21; Fist day of summer;longest day of the year

Vernal Equinox

March 21; First day of spring; Equal number of daylight and dark hours

How does sunlight hit the Earth?

Most direct sun at the equator with less direct sun as you approach the poles

Which direction does the sun seem to move?

Rises in east and sets in the west

What was the name of the first person and satellite in space?

Russian Yuri Gagarin; Sputnik I

Autumnal Equinox

September 23; First day of Autumn; Equal number of daylight and dark hours

What calander do we use?

The Roman Calander; 11 months 30 or 31 days plus February with 28 or 29

What causes the seasons?

The tilt of the Earth and its orbit around the sun

When and how was the moon formed?

a large object hit Earth when it was forming and a blob or matter broke off and formed it

What is the moon?

a natural satellite orbitting the Earth

What does eclipse mean?

blocked out

What causes the phases of the moon?

caused by the changes in the relative positions of the moon, Earth and sun

What are maria?

dark, flat areas - used to be thought of as oceans

How do we study the moon?

from rocks gathered by astronauts

What causes the tides?

gravity; differences in how much the moon pulls on different parts of the Earth

What is a spring tide?

greatest difference between the high and low tides; New Moon and Full Moon Phase

Why is a day added to February every 4 years and what is it called?

it takes four years for each 1/4 of a day to add up to an extra day on February 29 called Leap Year

What are highlands?

mountains on the moon

What is latitude?

parallel lines that measure north and south

Shuttle program

reusable U.S. spacecraft; first launched in 1981

What is a geosynchronous orbit?

revolution aound the Earth at the same rate that the Earth rotates

What are craters?

round pits on the surface caused by impacts of meteoroids

What is the shape of Earth's orbit?

slightly flattened circle; oval

astronomy

study of the moon, stars and other objects in space

What is an umbra?

the darkest part of a shadow during an eclipse

axis

the imaginary line that passes through Earth's center and the North and South Poles

What is a neap tide?

the least difference the high and low tides; 1st Quarter and Last Quarter Moon Phase

What is a penumbra?

the lighter part of the shadow during an eclipse

What affects gravity?

the masses of the objects and the distance between the objects

What is a lunar eclipse?

the moon blocked out by Earth's shadow

What is revolution?

the movement of one object around another

What is an orbit?

the path that an object takes around another

What are tides?

the rise an fall of water every 12.5 hours; alternating high and low roughly every 6 hours

What is a solar eclipse?

the sun blocked out by the moon

Why are there satellites in space?

used for communications, navigation, collecting weather data, and research

Which direction does Earth rotate?

west to east

Where do you see a partial solar eclipse?

when you are in the penumbra

Where do you see a total solar eclipse?

when you are inside the umbra