Important Facts About Solar Systemt
The Solar System was formed approximately 4.6 billion years ago and consists of the Sun, planets, dwarf planets and other astronomical objects bound in its orbit. The formation was cause by the collapse of a giant molecular cloud, the mass at the center collecting to form the Sun and a flat disk of dust around it which the planets and other bodies would eventually be formed from.
• 99.86% of the system’s mass is found in the Sun and the majority of the remaining 0.14% is contained within the solar system’s eight planets.
• The four smaller inner planets, also known as the “terrestrial planets” (Mercury, Venus, Earth and Mars), are primarily composed of rock and metal.
• The four outer planets, also known as the “gas giants” (Jupiter, Saturn, Uranus and Neptune), are substantially larger and more massive than the inner planets.
• The two innermost gas giants, Jupiter and Saturn, are the larger of the four and are composed mainly of hydrogen and helium.
• The two outermost gas giants, Uranus and Neptune, are composed largely of ices, (water, ammonia and methane) and are sometimes also referred to as the “ice giants“.
• Other objects of note in the Solar System are the dwarf planets (Ceres, Pluto, Haumea, Makemake & Eris),moons, asteroids, the asteroid belt, comets and the Kuiper belt.
Below is a brief overview of the eight primary planets in our solar system, in order from the inner solar system outward:
1. Mercury
2. Venus
3. Earth
4. Mars
5. Jupiter
6. Saturn
7. Uranus
8. Neptune
9. Pluto (Dwarf Planet)
1.MERCURY:
• Discovery: Known to the ancients and visible to the naked eye
• Named for: Messenger of the Roman gods
• Diameter: 3,031 miles (4,878 km)
• Orbit: 88 Earth days
• Day: 58.6 Earth days
IMPORTANT FACTS:
1. Mercury is the closest planet to the sun and is also the smallest of the eight planets in our solar system.
2. For every 2 orbits of the Sun, which takes around 88 Earth days, Mercury completes three rotations of its axis.
3.It is gravitationally locked and this rotation is unique to the solar system.
4. Every seven years or so, Mercury can be seen from Earth passing across the face of the Sun.
5. Mercury is the smallest planet in the solar system.
6. After the Earth, Mercury is the second densest planet.
7.Mercury has no moons or rings.
8. The planet has just 38% of the gravity on Earth.
9. Mercury is only the second hottest planet.
10. Only two spacecraft have ever visited Mercury.
2.VENUS:
• Discovery: Known to the ancients and visible to the naked eye
• Named for: Roman goddess of love and beauty
• Diameter: 7,521 miles (12,104 km)
• Orbit: 225 Earth days
• Day: 241 Earth days
IMPORTANT FACTS:
1. Venus, the second planet from the sun.
2. enus does not have any moons or rings.
3. Venus is nearly as big as the Earth with a diameter of 12,104 km.
4. Venus is thought to be made up of a central iron core, rocky mantle and silicate crust.
5. A day on the surface of Venus (solar day) would appear to take 117 Earth days.
6. A year on Venus takes 225 Earth days.
7. The surface temperature on Venus can reach 471 °C.
8. Venus is also known as the Morning Star and the Evening Star.
9. Venus is often called the Earth’s sister planet.
10. Venus is the second brightest object in the night sky.
3.EARTH:
• Diameter: 7,926 miles (12,760 km)
• Orbit: 365.24 days
• Day: 23 hours, 56 minutes
IMPORTANT FACTS:
1. Earth is the Only Planet Known to Have Life.
2. Earth is the third planet from the Sun and is the largest of the terrestrial planets.
3. The Earth was formed approximately 4.54 billion years ago and is the only planet to support life.
4. Earth is Almost a Sphere.
5. Earth is the only planet not named for a mythological god or goddess.
6. Earth’s atmosphere is composed of 78% nitrogen, 21% oxygen.
7. Earth has a very powerful magnetic field.
8. The highest point found on Earth is Mount Everest.
9. Earth is the most dense planet in the solar system.
10. Earth’s atmosphere divided in 5 sections from the surface: Troposphere (0-13 km), Ozone Layer (13-25 km), Stratosphere (25-50 km), Mesosphere (50-75 km), and Thermosphere (75-150 km).
4. MARS:
• Discovery: Known to the ancients and visible to the naked eye
• Named for: Roman god of war
• Diameter: 4,217 miles (6,787 km)
• Orbit: 687 Earth days
• Day: Just more than one Earth day (24 hours, 37 minutes)
IMPORTANT FACTS:
1. Mars and Earth have approximately the same landmass.
2. Mars has the largest dust storms in the solar system.
3. Only 18 missions to Mars have been successful ( As of September 2014).
4. This is the fourth planet from the sun, is a cold, dusty place.
5. Mars is sometimes called the Red Planet because of the brownish-red color of its surface.
6. Mars is the second smallest planet in the solar system.
7. Mars Used To Have A Thicker Atmosphere.
8. Mars Has Two Moons And One Of Them Is Doomed.
9. Mars Has Methane In Its Atmosphere.
10. On mars sunsets is blue.
5.JUPITER:
• Discovery: Known to the ancients and visible to the naked eye
• Named for: Ruler of the Roman gods
• Diameter: 86,881 miles (139,822 km)
• Orbit: 11.9 Earth years
• Day: 9.8 Earth hours
IMPORTANT FACTS:
1. The fifth planet from the sun, Jupiter is huge and is the most massive planet in our solar system.
2. Jupiter has the shortest day of the eight planets.
3. Jupiter has at least 67 moons in satellite around the planet.
4. Jupiter is the fourth brightest object in the solar system.
5. It is so big that more than 1300 Earths could fit inside it.
6. Jupiter has many moons circling around it. Four of these moons are bigger than Pluto.
7. Jupiter has a very strong magnetic field, you would weigh two and a half times as much as you would on Earth.
8. Jupiter has a very unique cloud layer.
9. Jupiter orbits the Sun once every 11.8 Earth years.
10. Jupiter has a thin ring system.
6.SATURN:
• Discovery: Known to the ancients and visible to the naked eye
• Named for: Roman god of agriculture
• Diameter: 74,900 miles (120,500 km)
• Orbit: 29.5 Earth years
• Day: About 10.5 Earth hours
IMPORTANT FACTS:
1. The sixth planet from the sun is known most for its rings.
2. Saturn is the second largest planet in our solar system.
3. The most common nickname for Saturn is “The Ringed Planet”.
4. Saturn is the flattest planet.
5. Saturn can be seen with the naked eye.
6. Saturn has 150 moons and smaller moonlets.
7. Saturn has the fastest winds of any other planet in our solar system.
8. Saturn is 1,424,600,000 km from the Sun. This is around 0.9 billion miles.
9. Saturn is the least dense planet in the Solar System.
10. Saturn has only been visited 4 times by spacecraft.
7.URANUS:
• Discovery: 1781 by William Herschel (was thought previously to be a star)
• Named for: Personification of heaven in ancient myth
• Diameter: 31,763 miles (51,120 km)
• Orbit: 84 Earth years
• Day: 18 Earth hours
IMPORTANT FACTS:
1. The seventh planet from the sun, Uranus is an oddball.
2. Uranus was officially discovered by Sir William Herschel in 1781.
3. Uranus is often referred to as an “ice giant” planet.
4. Uranus cannot be seen from the Earth without a telescope.
5. It has the third-largest planetary radius and fourth-largest planetary mass in the Solar System.
6. Uranus wind speeds can reach up to 900 km per hour.
7. Uranus is the coldest planet in the solar system.
8. Uranus has 27 moons.
9. A year on Uranus is equal to 84.01 Earth Years (orbit around the sun).
10. In 1986, Voyager 2 visited Uranus, until then, little was known about this planet.
8.NEPTUNE:
• Discovery: 1846
• Named for: Roman god of water
• Diameter: 30,775 miles (49,530 km)
• Orbit: 165 Earth years
• Day: 19 Earth hours
IMPORTANT FACTS:
1. The eighth planet from the sun, Neptune is known for strong winds, sometimes faster than the speed of sound.
2. Neptune is a gaseous planet, composed of hydrogen, helium, methane, with traces of ammonia and water.
3. The only spacecraft ever to visit Neptune was Voyager 2 in 1989.
4. It takes Neptune 164.8 Earth years to orbit the Sun.
5. Neptune has the second largest gravity of any planet in the solar system second only to Jupiter.
6. If you weigh 100 lbs, your weight on Neptune would be 113 lbs. (multiply your actual weight by 1.13).
7. One Neptune day is equal to 16 hours in Earth time.
8. One Neptune year is equal to 164.83 Earth Years.
9. Neptune has 14 moons.
10. Neptune spins on its axis very rapidly.
9.PLUTO (DWARF PLANET):
• Discovery: 1930 by Clyde Tombaugh
• Named for: Roman god of the underworld, Hades
• Diameter: 1,430 miles (2,301 km)
• Orbit: 248 Earth years
• Day: 6.4 Earth day
IMPORTANT FACTS:
1. Once the ninth planet from the sun, Pluto is unlike other planets in many respects. It is smaller than Earth's moon.
2. Pluto was discovered on February 18th, 1930 by the Lowell Observatory.
3. Pluto has five known moons.
4. Pluto is one third water.
5. Pluto has a heart shape on its surface.
6. Pluto is the only known dwarf planet with an atmosphere.
7. It takes about five hours for sunlight to reach Pluto.
8. No spacecraft has ever visited Pluto. However, the spacecraft New Horizons, which was launched in 2006, is scheduled to fly by Pluto in 2015.
9. Officially, Pluto’s name is now asteroid number 134340 after being downgraded from a planet to a dwarf planet.
10. On Pluto, the sun rises and sets about once a week.
ADDITIONAL FACTS ABOUT SOLAR SYSTEM
BLACK HOLE:
IMPORTANT FACTS:
1. A region of space having a gravitational field so intense that no matter or radiation can escape.
2. You can’t directly see a black hole.
3.Famous black holes are Cygnus X-1, Sagittarius A*, M87 and Centaurus A.
