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82 Cards in this Set

  • Front
  • Back
A _______ is described as a giant dirty snowball. It is composed of frozen gases, water,______ and icy lumps.
comet, dust
A distinguishing feature of Jupiter is _____ _______ ______ Spot. This spot is a giant storm that is 30,000 miles long and _______ miles wide.
The Giant Red, 10,000
________ is a region beyond the Earth’s atmosphere where there is very little molecular activity.
Many people generally agree that space occurs at about _____ miles outward from Earth.
The _________ includes everything, stars, planets, galaxies, animals, plants and humans.
Space is characterized by a lack of __________.
Small or low gravity is called ______________.
Our sun, which is the center of our solar system, is but a tiny spot in our _________. In fact, there are 200 billion _____ in our galaxy, and our galaxy is just one of millions of galaxies.
galaxy, suns
A _________ is an enormous collection of stars, and these stars are arranged in a particular shape.
The three main shapes of galaxies are _________, _________ and __________.
elliptical, spiral and irregular
Elliptical galaxy is oval shaped. _________ galaxy has arms spiraling outward from a center. _________ galaxy has no particular shape.
spiral, irregular
Our galaxy is called the ________ ______. It is ________ shaped.
Milky Way, spiral
Galaxies contain giant clouds of gas and dust called ___________.
_________ are bodies of hot gases.
The _______________ is a part of the atmosphere divided by its electrical activity.
The ______ is the primary cause of the Van Allen belts.
Most stars are composed of __________ and ________ in their gaseous state.
hydrogen and helium
About half of all stars come in pairs with the stars sharing the same gravitational center. These are called _________ stars.
A ___________ is a grouping of stars that look like imaginary figures.
The Big Dipper is an example of a ______________.
Our _______ _______ is the sun and the bodies that orbit around it.
solar system
Without heat and light, the Earth would be a lifeless, _____-_________ planet.
The central star of our solar system is the _______.
The Earth is _____ _________ miles from the sun.
93 million
The sun is composed of about ____% hydrogen, ___% helium and minor amounts of several other elements.
90, 9
The temperature of the sun ranges from ______degrees C in its coolest regions to over ____ _______ degrees C at its center.
4200, 15 million
_________ are darker, cooler areas of the sun.
_______ _______ are short-lived high-energy discharges.
solar flares
_______ _____________ are larger and longer lasting high-energy discharges.
solar prominences
The Earth’s Moon has a diameter of about ______ miles, which is about ___ of the Earth’s diameter.
2155, ¼
The distance from the Earth to the Moon varies from approximately ______ miles at its farthest point to ________ miles at its nearest point.
252,000 221,000
The Moon rotates on its axis in the same amount of time it takes to orbit the Earth, _______ days. Therefore, the same side of the Moon, the near side, always faces the Earth.
When the Moon is on the side of the Earth nearer the sun, the Moon is ______.
When it is on the opposite side of the Earth, the Moon is _______.
Primarily, the Moon has two types of terrain, ___________ and ___________.
highlands lowlands
Temperatures on the Moon range from about _____degrees in the day, to below ______degrees at night.
250, -250
___________ is the closest planet to the sun, and it revolves around the sun every _____ days.
Mercury, 88
_________ is the closest planet to Earth. It revolves around the sun in _____ days.
Venus, 225
Venus is the ________ planet in the solar system with temperatures in excess of _____degrees.
hottest, 850
__________is the only known planet to rotate in a clockwise manner.
The atmosphere of Venus is 96% _________ __________ and 4% nitrogen.
carbon dioxide
The Earth’s atmosphere contains 78% ___________ and 21% ____________.
nitrogen, oxygen
The surface of our planet is covered with over 67% __________.
The Earth revolves around the sun in _______ days.
Mars is known as the _____ planet and even with the naked eye we can see this _______ color.
red, red
The red color of Mars is due to the ______ and _______ covering the surface.
rock, dust
The surface of Mars is covered with deserts, high mountains, deep craters and huge ____________.
One of Mars’ ____________ is the highest known mountain in our solar system.
The atmosphere of Mars consists of 95% _________ ___________.
carbon dioxide
Daytime temperatures on Mars reach ____degrees F, while nighttime temperatures can dip to______degrees F.
65, -130
In July 1997, the space probe called the ______ _____________ landed on Mars. The next day the rover, Sojourner Truth began its exploration of the planet. The rover was ____ feet long and _____ foot tall.
Pathfinder, two, one
Next to Earth, _______ has the most favorable conditions for life of any of the other planets in our solar system.
__________ is the largest planet in our solar system.
Jupiter is ____ times larger than Earth.
Jupiter is a gas giant, with ___________ accounting for about 90% of the atmosphere, followed by helium, __________ and ammonia.
Jupiter is known for its ____ moons.
The rings are the most recognizable feature of ________.
Saturn's rings are made of icy chunks of ______ ranging from tiny particles to large _________.
rock, boulders
Saturn's main rings are made up of hundreds of narrow __________.
Saturn's entire ring system is about one mile thick and extends about _________ miles from the planet.
Saturn has an _____ _____ core surrounded by metallic hydrogen with an outer layer of hydrogen and helium.
icy, rock
It takes Saturn ____ years to revolve around the sun.
The winds of Saturn have been known to reach ______ mph.
Saturn is ____ _______ miles from the sun.
900 million
________, one of the moons of Saturn, is the only moon in the solar system to have its own ______________.
Titan, atmosphere
___________ is about 1.7 billion miles from the sun. It has a rocky core surrounded by water, ammonia and methane, in both ice and _________ form.
Uranus, liquid
Uranus revolves around the sun in ____ years.
Daylight on Uranus lasts for ___ years followed by ___ years of night.
42, 42
Uranus also has 11 very narrow and black ________ around it.
Neptune is about ___ ________ miles from the sun and takes ____ Earth years to complete an orbit.
3 billion, 165
Neptune’s atmosphere consists of ___________, helium and __________.
hydrogen, methane
The ___________ gives Neptune a bluish color.
___________ is the most windy planet in the solar system. It has recorded winds of _______ mph.
Neptune, 1340
________ is the smallest planet in our solar system. It is a dark and ________ planet.
Pluto, frozen
Pluto's surface is made up of __________ ________.
methane frost
Asteroids, comets and meteoroids are collectively thought of as _________ orbiting in space.
______________ are chunks of rock that range in size from particles of dust to some that are a few hundred miles across.
Most _______ travel in an orbit between Mars and Jupiter. This area is known as the ________ ______.
asteroids, asteroid belt
_______ are tiny particles of dust and sand that are usually leftover from a comet.
If a meteoroid enters the Earth’s atmosphere it is called a _______.
Meteors that actually hit the Earth are called ______________.
Mercury's daytime temperature reaches_____degrees F, while its nighttime temperatures reach _____degrees F.
800, -300