Halley''s orbit period is, on average, 76 Earth years. This corresponds to an orbital circumference around the Sun of about 7.6 billion miles (12.2 billion kilometers). The period varies from appearance to
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Mars is the fourth planet from the Sun, and the seventh largest. It''s the only planet we know of inhabited entirely by robots.
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During a "full moon," the hemisphere of the Moon we can see from Earth is fully illuminated by the Sun. And a "new moon" occurs when the far side of the Moon has full sunlight, and the side facing us is
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Without the Sun''s energy, life as we know it could not exist on our home planet. From our vantage point on Earth, the Sun may appear like an unchanging source of light and heat in the sky. But the Sun is
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Our solar system consists of our star, the Sun, and everything bound to it by gravity – the planets Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune; dwarf planets such as Pluto;
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The Sun is the star at the heart of our solar system. Its gravity holds the solar system together, keeping everything – from the biggest planets to the smallest bits of debris – in its orbit.
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The inner, main region of the Kuiper Belt ends around 50 AU from the Sun. Overlapping the outer edge of the main part of the Kuiper Belt is a second region called the scattered disk, which continues
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NASA''s real-time science encyclopedia of deep space exploration. Our scientists and far-ranging robots explore the wild frontiers of our solar system.
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Solar System Our Solar System Sun Kuiper Belt Oort Cloud Beyond Our Solar System Eclipses
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