Short Notes – Space and Solar System – General Knowledge Update
Last updated: December 16, 2011 by Sarbjit+
Here is another GK Update from GJ Tutorial. This information is useful for General Knowledge section of various entrance examinations and recruitment exams.
This is very general information meant specifically for people who have not studied science as a subject after class 10 (So you forgot all this!! Right!!). This is meant to be a refresher and we believe you do not need to read more for this as far as GK is concerned.
So Lets Recall what we learnt when we were young!!
Part 1: Space
Everything that exists.
All of space and time taken together.
Our Solar System is a part of galaxy called "Milky Way". The nearest galaxy is "Andromeda Nebula".
The Sun and the collection of celestial bodies that orbit it. These include the nine planets (Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto) and their 60 moons, the asteroid belt, the comets and other heavenly bodies. (Diameter: 1170 Crore Km Approx).
The solar system's nearest neighbor in the galaxy is the triple star system Alpha and Proxima Centauri, which is 4.3 light-years away from the sun.
The planets were formed out of the gas clouds surrounding the newly born Sun (a Star). This gave birth to the Solar System.
Age of Solar System:
About 4600 million years.
1. Sun is an average sized Star (A Dwarf Star).
2. Forms 99% of the mass of Solar System.
3. Surface Temperature: 5,800 kelvins (K)
4. Core Temperature: 15,000,000 K
5. Provides us heat and light, generated by a nuclear reaction.
6. Photosphere: Glowing Surface of Sun.
7. Chromospheres: The inner reddish region.
8. Corona: The outermost layer of sun, visible during eclipse.
The bodies revolving around the sun (at the same time rotating on their own imaginary axis).
Nine Planets are:
2. Venus (Rotates clockwise)
7. Uranus (Rotates clockwise)
9. Pluto (Not considered a planet any more)
Note: Pluto had been considered a planet from the time of its discovery in 1930 until 2006, when the International Astronomical Union (the organization that classifies astronomical objects) created the dwarf planet category.
How to Remember All The Planets in Order:
use the phrase "My Very Educated Mother Just Showed Us Nine Planets" where the first letter of each word reminds us of a planet starting from Mercury to Pluto.
Types of Planets:
1. Inferior planets: Mercury and Venus, whose orbits lie between the sun and Earth
2. Superior Planets: The planets whose orbits lie beyond Earth's orbit are the superior planets
OR: based on similarity of structure.
1. Inner Planets: (Mercury, Venus, Earth, and Mars)
2. Outer Planets (Jupiter, Saturn, Uranus, and Neptune). Also called Jovian (Jupiter Like) Planets.
They revolve around planets.
1. Earth has only one moon.
2. Mars has two moons
3. Jupiter and Saturn have more than 50 known moons each
4. Uranus has more than 25
5. Neptune has more than 10.
6. Saturn's moon Titan is Largest Satellite (larger than mercury).
7. Rings: Jupiter, Saturn, Uranus, and Neptune have planetary rings made up of innumerable tiny satellites.
They are many smaller bodies that circle the sun in orbits that lie in a belt between Mars and Jupiter.
Ceres is the largest asteroid.
Meteoroids, Meteors (Shooting Star), Meteorites
Small chunks of stony or metallic matter from outer space that enter the Earth's atmosphere and vaporize.
1. Before they encounter Earth's atmosphere these are called meteoroids.
2. Once they enter the atmosphere, they are called meteors.
3. Most meteors are so tiny that they vaporize completely soon after entering the atmosphere. The large meteors that survive the fall to Earth are called meteorites.
Have a Question?? Please leave a comment or use our Contact Form.
Also Contact Us For B.Ed./Bank PO General Knowledge Notes and current GK Update.
Category: General Knowledge
Tags: Current GK, General Knowledge