The Sun is a star found at the center of the Solar System. It makes up around 99.86% of the Solar System’s mass. At around 1,392,000 kilometers (865,000 miles) wide, the Sun’s diameter is about 110 times wider than Earth’s. Around 74% of the Sun’s mass is made up of hydrogen. Helium makes up around 24% while heavier elements such as oxygen, carbon, iron and neon make up the remaining percentage. Light from the Sun reaches Earth in around 8 minutes. The Sun’s surface temperature is around 5500 degrees Celsius (9941 degrees Fahrenheit), so pack plenty of sunscreen if you plan on visiting!
Mercury is a small planet which orbits closer to the sun than any other planet in our solar system. As well as being very hot, it features a barren, crater covered surface which looks similar to Earth's moon. Being so close to the Sun, the daytime temperature on Mercury is scorching - reaching over 400 Degrees Celsius. At night however, without an atmosphere to hold the heat in, the temperatures plummet, dropping to -180 Degrees Celsius. Mercury has a very low surface gravity. Mercury has no atmosphere which means there is no wind or weather to speak of. There is also no water on the surface of Mercury, it is possible however that there could be water underneath the surface.
Venus is a fascinating planet that is similar in size to Earth but very different in regards to atmosphere and surface conditions. Its thick clouds lock in the heat while the surface rages with active volcanoes. The atmosphere of Venus made up mainly of carbon dioxide. Venus is surrounded by clouds consisting of mercury, ferric chloride hydrocarbons and sulphuric acid. These clouds create the most corrosive acid rain found anywhere in our solar system. The clouds are so thick that little light even reaches the surface. The light that does reach the surface is converted to heat and cannot escape the atmosphere making Venus the hottest planet at around 500 Degrees Celsius. The surface of Venus is often described as a "stormy desert" full of many craters and very active volcanoes. The surface is also likened to molten lead. Venus features no liquid water.
The Moon is the Earth’s only natural satellite. A natural satellite is a space body that orbits a planet, a planet like object or an asteroid. The Moon orbits the Earth every 27.3 days. Mons Huygens is the tallest mountain on the Moon, it is 4700 metres tall, just over half the height of Mt Everest (8848m). The effect of gravity is only about one fifth (17%) as strong on the surface of the Moon compared to the strength of gravity on the surface of the Earth. The surface of the Moon features a huge number of impact craters from comets and asteroids that have collided with the surface over time. The Moon is very hot during the day but very cold at night. The average surface temperature of the Moon is 107 degrees Celsius during the day and -153 degrees Celsius at night. The Earth’s tides are largely caused by the gravitational pull of the Moon.
Mars, or the 'Red Planet' as it is sometimes known, has a dusty, rocky surface and a thin atmosphere. Its relatively calm conditions and close proximity to earth make it the most likely destination for future planet exploration by humans. It has already been visited by a number of Mars Rovers in successful (and unsuccessful) robotic missions. These highly advanced robots gather samples and record important scientific data for scientists back on Earth to study. Mars has many massive volcanoes and is home to Olympus Mons, the largest volcano in our solar system, at 21km high and 600km wide. Mars has many channels, plains and canyons on the surface which could have been caused by water erosion in the past.
Jupiter is the largest planet in our solar system. Its famous 'Red Spot' and raging gas storms give it an impressive if not intimidating appearance. As well as having many moons, Jupiter also has a number of rings similar to that of Saturn but much less noticeable. Jupiter is the largest planet in our solar system. It is so big that more than 1300 Earths could fit inside it. Thick, colorful clouds of deadly poisonous gases surround Jupiter. Jupiter has many storms raging on the surface, most notably the big red spot which is the largest hurricane in our Solar System. It's been raging for over three hundred years. Jupiter has many moons circling around it. Four of these moons are bigger than Pluto.
Perhaps the most beautiful planet in our solar system (other than earth of course) due to its spectacular ring system, Saturn is a gas giant that features many extreme physical features and atmospheric conditions. Saturn is the second largest planet in our solar system and is another gas giant. It is surrounded by a system of rings that stretch out into space for thousands of kilometres. The rings are made up of millions of ice crystals, some as big as houses and others as small as specks of dust. Saturn is very light as it is made up of more hydrogen than helium so it is less dense. If we could fit Saturn into a bathtub it would float (but that would have to be one big bathtub!).
Uranus likes to be a bit different. It shows off a majestic blue/green haze due to its high levels of methane gas and rolls like a barrel rather than spinning like Earth and the other planets in our Solar System. Uranus spins lying on its side (like a barrel), this is perhaps due to a large collision early in its formation. Uranus was the first planet discovered by telescope. Uranus’s atmosphere is mostly hydrogen but it also contains large amounts of a gas called methane. Methane absorbs red light and scatters blue light so a blue-green methane haze hides the interior of the planet from view. Scientists have theorized that under the hydrogen-methane atmosphere is a hot, slushy ocean of water, ammonia and methane thousands of miles deep wrapped around a rocky core.
Neptune is a large planet that experiences extreme atmospheric weather conditions. After the demotion of Pluto, it now holds the distinction of being further away from the sun than any other planet in our solar system. Neptune is a large planet, nearly four times the size of Earth. Neptune suffers the most violent weather in our Solar System. Storms have been spotted swirling around its surface and freezing winds that blow about ten times faster than hurricanes on Earth make it the windiest planet. Neptune is a large, water planet with a blue hydrogen-methane atmosphere and faint rings. Neptune is covered in thin wispy white clouds which stretch out around the planet.
Don't forget Pluto! Sure it may not be officially recognized as a planet anymore but it's still there and offers a lot of interesting facts and cool information. Pluto was the smallest and furthest planet from the Sun in our solar system, now it is not even officially recognized as a planet! In 2006 Pluto was demoted to the status of dwarf planet. Because it is so far away from the sun it is very cold with temperatures ranging from -235 Degrees Celsius to -210 Degrees Celsius. Pluto consists of rock with a very thick coating of ice. The atmosphere of Pluto consists of nitrogen with some carbon monoxide and methane.
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