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Venus is often called the Earth's sister planet. The Earth and Venus are very similar in size with only a 638 km difference in diameter, Venus having 81.5% of the Earth's mass.

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Neptune is the eighth and farthest planet from the Sun, at a distance of about 4.5 billion km (2.8 billion miles) or 30.07 AU.

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The largest planet in our solar system by far is Jupiter, which beats out all the other planets in both mass and volume. Jupiter's mass is more than 300 times that of Earth, and its diameter, at 140,000 km, is about 11 times Earth's diameter.

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Jupiter is the fastest spinning planet in our Solar System rotating on average once in just under 10 hours. That is very fast especially considering how large Jupiter is. This means that Jupiter has the shortest days of all the planets in the Solar System.

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75% of the Sun's mass is Hydrogen. Hence, Hydrogen gases is most predominant in the Sun.

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Earth is the fourth smallest of the planets-though in terms of the rocky planets, it's the largest-but it's the most dense.

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In observational astronomy, a double star or visual double is a pair of stars that appear close to each other as viewed from Earth, especially with the aid of optical telescopes. This occurs because the pair either forms a binary star (i.e. a binary system of stars in mutual orbit, gravitationally bound to each other) or is an optical double, a chance line-of-sight alignment of two stars at different distances from the observer.