Astronomy Lesson 2 Year 1 : Introduction to Universe

Roselle is standing behind the garage door of the Astronomy Tower. Students enter and they see a big planetary system above their heads.

Hello, Hello, and welcome back to Astronomy! I hope you are used to the class timings, and the route to the tower too! I might say that you're having a hard time adjusting to the timings at midnight, are you not? But, I'm pretty sure you will get adjusted to it. Have you observed the order above your head? It is a model of the Solar System which displays the motions and places of all the Planets.

Image Collection can be found here.

Today, we would be covering some information about our Galaxy. You could read chapter 2 of the textbook after the lesson to gain some extra knowledge, of course!

Before, I will cover some invention details about our Solar System. How was it created? Our galaxy is known as Milkyway. About many years ago, all the planets collided together, many meteors and asteroid rocks assembled and caused a big blast, known as the Big Bang which assembled the rocks.

The theories listed in your textbook is a possibility, but it may not be true too. That's what my mother did for me, she told me this story, and when I was grown up, I got to know that it was simply a technique that enhanced my interest in the topic of Astronomy.

Planets

Planets: Planets are astronomical heavenly bodies that are located in the sky, which orbit a star or an astral body, which is adequately massive to get rounded off by its gravity.

Mercury: Mercury is the smallest planet in our solar system. It has no moons and revolves the fastest. It takes 59 Earth days to complete one revolution, while the rotation takes 75.97 days.

Venus: Earth and Venus are like twins, as they are of the same size. It is the hottest planet as, besides being closer to the sun, its surface is filled with carbon dioxide which makes it hot. It spins anti-clockwise.

Earth: The Earth is the only planet that is said to have people living till now, and that is where we all live. Most of the surface is covered with water, so it is known as "The Blue Planet". You will learn more about the Earth in your further lessons.

Mars: Mars is known as the ''Red Planet". Muggle Scientists are currently discovering more about Mars, and have sent many Satellites to Mars, and are looking for life on it. It has two moons named Phobos and Deimos. Phobos is a doomed moon as Phobos orbits so near to Mars that gravitational tidal forces are dragging it down. In 100 million years or so, Phobos likely will be shattered by stress caused by the relentless tidal gorges.

Jupiter: Jupiter is the largest planet in the Solar System. It rotates the fastest and revolves the slowest. You cannot land on Jupiter as it is a Gas Giant. It even has the largest number of Moons. It has a big storm on it, known as the Great Red Spot.

Saturn: Saturn, again being a Gas Giant, does not have a solid surface, and as defined, is made of Hydrogen and Helium mostly. After every 29 and a half years, the planet appears ringless. Only a few satellites have visited this planet.

Uranus: It has 27 known moons yet. It rotates west to east(anti-clockwise), but it rotates on its edge. The extreme pressures of these planets could even destroy a spacecraft that visited Uranus!

Neptune: Neptune cannot sustain life, as it is very cold and far away from Earth. It has 14 known moons and is an Ice and Gas Giant. It is made up of Helium and Methane mostly.

Star Constellations

Star Constellations are stars that join other stars in the sky and make a shape, and which is approved by the Government and is named.

There are many constellations, such as Orion, for instance.

Orion

Orion is one of the popular constellations. More information about it is provided below.

• Name: Orion

• Best Viewing Time: December to February

• Size: 594 Square Degrees

• Example: Bellatrix

Meteors

Meteors are also referred to as Shooting Stars. They burn up in the Solar System and come running towards Earth/Any Other Planet that is present. Here is a short video about their 3 names, which are Meteor, Meteoroid, Meteorite :

When they are in space, they are known as Meteoroids. When they have burned and on the way to land, they are called Meteors. When they have landed on a surface, they are known as Meteoroids. A Meteor Shower is common across 30 times a year.

Asteroid

Asteroids are small, rocky objects that orbit the sun and are much smaller than a meteoroid. They do not lit up with fire. Unlike meteoroids, they are very much rare. The next asteroid to hit earth is in 2095, as predicted 5%

The four largest asteroids are Ceres, Vesta, Pallas, Hygiea.

Comets

Comets are cosmic frozen snowballs, which contain many gases such as Helium, Hydrogen, Methane. When it goes closer to the Sun, it shines up and is visible to Earth.

Dwarf Planets

These planets are the planets that are no longer part of the Solar System and have exited it. These are very small too. One of the vastest popular dwarf planets is Pluto, which was classified as a dwarf planet in 2006.

See you next week! I'm letting you off with a quiz. Class dismissed.

Definitions of Terms

Revolution: The moment of the planets around the Sun which causes seasons.

Rotation: The moment of planets in their axis which causes day and night.

Assignments