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30 Solar System Facts Everyone Should Know

What is the Solar System?

Solar System literally means a collection of objects (here celestial objects) of the Sun. It can be defined as a group or collection of objects with some form of interaction with each other and with the Sun.

Everyone knows about the basic details of our solar system. The solar system consists of the Sun and the objects that revolve around the Sun. The celestial objects are the planets, dwarf planets, asteroids, comets, minor planets, etc.

But there is a plethora of information that you don’t about this system. For example, there are two known dwarf planets of our solar system – Pluto and Eris. Today we are bringing you some less known solar system facts.

Solar System Facts 1-10

1. Solar system consists of only one star, and that is the Sun. There are 8 planets in the solar system. The eight planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Neptune, and Uranus.

2. There are two known dwarf planets – Pluto and Eris. The other three objects that are likely to be considered dwarf planets in the future are Ceres, Haumea, and Makemake.

3. There are around 575 natural satellites known to humanity. Out of the 575 natural satellites, 185 are planetary, and the rest 390 belong to minor planets. The total number of minor planets are 796,354. Known comets are 4,143 in number.

4. The nearest stars of the solar system is Proxima Centauri and Alpha Centauri. The nearest known planetary system is the Proxima Centauri.

5. Mercury is the closest planet to the Sun, but it is not the hottest planet. The hottest planet is Venus. The reason for this is the atmosphere of Venus is quite thick (100 times thicker than Earth’s atmosphere). Hence, the average temperature of Venus is 875 degrees F or 468 degrees Celsius. In contrast, the maximum temperature on Mercury is 840 degrees F or 448 degrees Celsius.

6. The width of Pluto is much smaller than the USA. From Northern California to Maine, the distance is 4,700 kilometers or 2,900 miles. The width of Pluto is 1,473 miles or 2,371 kilometers.

7. Did you know that we live in the Sun’s atmosphere? Yes, you read it right. Though Sun is around 93 million miles away from Earth, we are under its outer atmosphere called the heliosphere.  The heliosphere is considered to have a radius of 10 billion miles or 16 billion kilometers. How do we know this? Because our Earth experiences the Northern Lights and Southern Lights. It is the solar wind that generates these Auroras. Jupiter, Saturn, and even Neptune experience Auroras.

8. The atmosphere of the Sun is likely to have a shape of a tear, and the tail part is considered to extend some tens and thousands of billions of miles!

9. Even minor planets and asteroids have moons. Earlier it was thought that only big planets have moons, but the Galileo probe proved them wrong. In 1993, Galileo probe discovered that a 20-mile wide Ida, an asteroid, has a one-mile-wide moon, Dactyl.

10. It is estimated that Jupiter has the biggest ocean in the entire solar system. Jupiter is made up of hydrogen and helium. As per the mass and chemical composition of Jupiter and physics rules goes, below the clouds, the hydrogen should turn liquid because of the pressure. Computer models show that this would be the largest ocean of the solar system, and it has a depth of 25,000 miles or 40,000 kilometres (which is nearly the depth of our Earth).

Solar System Facts 11-20

solar system facts

11. There are some Martian rocks on our planet. Some of the meteorites found in the Sahara Desert, Antarctica, etc., show that they were from Mars. Some of the meteorites have pockets of gas in them, which is similar to Mars’ atmosphere. It is believed that some asteroid or a meteoroid must have hit Mars, or a huge volcanic eruption took place, which later collided with the Earth.

12. The element composition of Earth is a little different from others. Earth is mostly constituted or rare elements – oxygen, silicon, sulfur, nickel, magnesium, aluminum, etc. They are found rarely in our universe. The most abundant gases like hydrogen and helium escaped from Earth due to Sun’s heat.

13. The solar system’s edge is believed to be a thousand times away from Pluto. Most of us think that the solar system ends with Pluto. Still, many celestial objects were discovered beyond Pluto. Kuiper Belt Objects (KBO) extends around 50 to 60 AU (Astronomical Units).  Oort cloud is around 50,000 AU or at a distance of half a light-year from the Sun.

14. A supermassive black hole is present at the center of our Milky Way galaxy. Our Sun is 25,000 and 30,000 light-years away from the center of the galaxy. Milky Way is a spiral galaxy with curved arms of stars emerging from the center. The arm in which our Sun is present is called Orion Arm or Orion-Cygnus Arm.

15. If you are wondering how big our galaxy is, if you compare your hand to the Orion Arm, then the rest of the galaxy is the USA’s size!

16. The gravitational influence of the Sun extends around 122 AU, which is 93 million miles or 150 million kilometers.

17. Mercury experiences the most extreme fluctuations in temperature. In the day, the temperature may rise to 840 degrees F or 450 degrees Celsius. At night the temperature may drop down to -275 degrees F or -170 degrees Celsius.

18. The Earth is the densest planet in the solar system. It has a density of 5.52 grams/cubic centimeter. Mercury is the second densest planet. With a density of 0.687 g/cc or grams/cubic centimeter, Saturn is the least dense of all the planets.

19. Moon is the brightest object in the night sky. The next brightest object is Venus. On a clear day, you can actually see Venus during the daytime.

20.Venus can be seen before and after sunrise, and hence Romans and Greeks thought Venus to be two different entities. Romans called the two entities Lucifer and Vesper, while Greeks called them Phosphorus and Hesperus. Venus is famously known as the Morning Star and Evening Star.

Solar System Facts 21-30

solar system facts

21. Moon is moving away from the Earth by 3.78 centimeters or 1.48 inches every year. We see the same side of the moon all the time. It happens because the moon’s rotation and revolution around Earth take almost the same time.

22. Mars is named after Mars, the God of War for Romans. The tallest mountain of the solar system is present on Mars. It is called Olympus Mons and is 21 kilometers high and has a diameter of 600 kilometers.

23. It is believed that Mars had water in the past. The claim was supported by the dark stripes or dark stains on the cliffs and crater walls, as seen in the satellite images. It is also believed that Mars still has water in the form of ice.

24. Jupiter is so massive that it is 2.5 times massive than all the 8 planets combined! It is 318 times the size of Earth.

25. The fastest rotating planet in the solar system is Jupiter. It takes mere 10 hours to complete one rotation. The famous Red Spot on Jupiter measures 24,000 kilometers in diameter and is 12,000 to 14,000 kilometers high. The Red Spot itself can accommodate 2 to 3 Earths. The spot is present for the last 350 years.

26. Saturn is not the only planet to have rings. Jupiter and Uranus also have rings. An asteroid, too, can have rings. It takes 29 Earth years to complete one revolution, but it takes only 10 hours and 14 minutes to complete one rotation.

27. Pioneer 11, Voyager 1, Voyager 2, and Cassini-Huygen are the four spacecraft that visited Saturn. Cassini entered Saturn’s orbit in 2004 and sent information till 2017. Winds around the equator of Saturn can reach 1,800 kilometers an hour. The fastest winds of Earth reach only 400 kilometers an hour.

28. Venus and Uranus rotate in a retrograde direction or anti-clockwise direction. It is the only planet that rotates sideways and rolls around the Sun. It is also the first planet to be discovered using a telescope. William Herschel, the discoverer, wanted to name it ‘Georgian Sidus’ after King George III.

29. Uranus has 27 moons, and most of the moons are named after the characters from the literary works of Alexander Pope and William Shakespeare. It has the coldest planetary atmosphere in the solar system. The minimum surface temperature of Uranus is -224 degrees Celsius. Similar to Jupiter and Saturn, the rotation time is short, i.e., 17 hours. Still, it takes 84 Earth years to complete one revolution.

30. Neptune takes 16 hours to complete one rotation. It is the coldest planet of the solar system, with temperatures dipping to -221.45 degrees Celsius. Triton, one of Neptune’s moons, is captured in a synchronous rotation with Neptune. It rotates around the planet in an anti-clockwise direction and hence gives the notion that Triton is not formed the way other moons of Neptune are formed.

If you want us to write more solar system facts, do let us know in the comments.