Planets
By the current count of astronomers, our solar system includes 8 planets and 5 dwarf planets. The planets were formed during the process of solar system formation, when clumps began to form in the disk of gas and dusk rotating about our young Sun. Eventually, only the planets and other small bodies in the solar system remained. The four rocky planets at the center of the solar system Mercury, Venus, Earth, Mars, are known as the inner planets. Jupiter, Saturn, Uranus, and Neptune are all composed primarily of gas and are known as the outer planets. Find out more about the planets through the links below.
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Explore Planets
What is a Planet?
Do you know what a planet is? Guess what... astronomers are not quite sure what a planet is! ...Read more
Mercury
Mercury, the planet nearest the Sun, is the second smallest planet in the solar system. Only ...Read more
Venus
Fair but inhospitable Venus, a "Sister" planet to the Earth that is very different from our ...Read more
Mars
Mars, Earth's outer neighbor, is the fourth planet from the Sun. Mars' bright appearance and ...Read more
Jupiter
Jupiter is the largest planet in the solar system. When approached from afar, its fantastic ...Read more
Saturn
Saturn, the sixth planet from the Sun, has the most spectacular set of rings in the solar system. ...Read more
Uranus
Uranus, the seventh planet from the Sun, has its spin axis almost in the plane of its orbit ...Read more
Neptune
Neptune, the eighth and furthest planet from the Sun, is a very cold place. Its bluish color ...Read more
Dwarf Planets
In 2006 the International Astronomical Union (IAU) approved a new classification scheme for ...Read moreMore about Planets
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Did you know?
Did you know that there are no seasons on Venus?Did you know that Uranus is tilted so that its rotational axis is almost in the plane of the ecliptic?
Earth and Space Science Concept of the Day
Do you know what this word or phrase means?S-wave
xS-wave : An s-wave (for shear wave) is a seismic body wave that shakes the ground back and forth perpendicular to the direction the wave is moving
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Research Highlights
“Missing” Heat May Affect Future Climate Change
Scientists know that more of the Sun’s energy gets to our planet than leaves. It hasn’t always been this way. More energy is sticking around as heat because there are more heat-trapping greenhouse gases...Read more
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