The Planets Explained
The Planets Explained
There are many planets that make up our solar system - we here at VideoJug give you a brief overview in our film The Planets Explained.
Step 1: The planets
Our Solar system is in a Galaxy very similar to this one about ¾ of the way out from the centre. From the Earth our Galaxy can be seen stretching across the sky, we call it the Milky Way.
Step 2: The Sun
Our Sun is a medium sized, middle aged star amongst about 6 Billion other stars in the Galaxy. It has a surface temperature of over 6,000°C. The dark areas are called sunspots; these are magnetic storms coming up from the interior. The Sun is not 'burning' but instead it is a Nuclear reaction turning hydrogen into helium. And with x-ray it looks very violent indeed. But all life on Earth depends on The Sun.
Step 3: Mercury
Coming out from the Sun, the first Planet is Mercury, the Smallest of all the Planets. Mercury is not much bigger than our Moon and like the Moon it is covered in deep impact craters from meteorites. The surface is so hot it could melt lead. In ancient times Mercury was known as the messenger of the Gods because it moves so quickly. It goes around the Sun once every 88 days.
Step 4: Venus
Next is Venus. Because it is only visible either just after Sunset or before Sunrise it is often known as the Evening star or morning Star. It is the brightest of all the Planets that we can see in the sky. Venus is very similar in size to the Earth, but it is covered in a thick blanket of cloud. However, using radar we are able to see right through the clouds to the surface of the planet. These clouds are causing a runaway greenhouse effect making the temperature on the surface climb to over 400°C, hotter even than Mercury.
Step 5: Earth
Earth, the blue Planet and our home. 153 million km from the Sun, 4/5ths of it are covered in water. It was not until the 16th century that people realised that the Earth was actually a planet! From space the continents are easily visible; this is the straight of Gibraltar. It is the only Planet that we know of that has life on it...up to now!
Step 6: The Moon
The Moon is our nearest neighbour in space at 384,000km. The moon goes around Earth every 28 days but it always keeps the same face pointed towards us. The dark areas are called seas; they are not real seas of water, just areas of a different coloured material than the surrounding areas. The surface is pockmarked with thousands of craters caused mostly from impacts from meteorites over millions of years. There are also many high mountain ranges, some stretching for hundreds of miles. Between 1969 and 1972, 12 American astronauts landed on the Moon. The first two were Neil Armstrong and 'Buzz' Aldrin. Some of the later astronauts even took a car along with them to go exploring.
Step 7: Mars
Mars, the red Planet. Mars has polar ice caps made from frozen carbon dioxide. These grow and shrink throughout the Martian seasons. There are very high winds on Mars that create dust storms, sometimes covering the whole Planet. The surface is coloured red and is very barren and because of the winds it is much eroded. For many years it was believed that Mars had life on it. NASA has sent probes to Mars to search for life, but without much luck unfortunately. Mars has two, tiny, 'potato' shaped moons called Phobos and Deimos.
Step 8: Jupiter
Jupiter is the largest Planet in the solar system, but unlike the Earth it is not made from rock. It is a 'gas giant' made mostly from Hydrogen and Helium. It is so big it could easily swallow all the other Planets. Despite its size Jupiter spins very quickly, a day on Jupiter lasts just 10 hours. Jupiter has over 60 moons, the four largest moons were discovered by the Italian Astronomer Galileo with the very first telescope in the year 1610. The ‘great red spot' is believed to be a giant storm that has been raging in the upper clouds for over 300 years; it is 10 times bigger than the Earth!