The document covers various topics related to astronomy and the solar system, including the characteristics of planets, the sun, and celestial phenomena such as comets and meteors. It explains the earth's rotation, resulting seasons, and phases of the moon. Additionally, it highlights the composition and significance of asteroids and other celestial bodies in space.

1. The Earth and Beyond
By Gaurav Malhotra
Physics
Grade 7

2. Content Layout
▪ The Solar System and Space
▪ Days, Nights and Years
▪ The Seasons
▪ The Phases of the Moon
▪ Comets and Meteors and Asteroids
The Earth And Beyond

3. The Planet’s Orbits
Which Planet is the
largest?
Jupiter
Which Planet is the
smallest?
Mercury

4. The Sun
▪ Sun is a yellow, hot ball of glowing gasses, which are Helium
and Hydrogen.
▪ It consists of a strong gravitational force, which keeps the
planets in their orbit around the Sun.
▪ It is the center of the universe and its mass makes up 99.8% of
the Solar System.
▪ “No Sun No Life.” This phrase means that the Sun’s humongous
energy allows us to live and without it we won’t be able to live.
▪ The Sun’s core’s temperature is about 15 million C.

5. The Planets
Mercury:
▪ Mercury completes the orbit around the Sun in just 88 Earth
Days.
▪ It has extreme temperatures in the day and night. Daytime
temperatures can go up to 430 C and night time temperatures
can fall down massively to -180 C.
▪ It has a very thin atmosphere which also escapes into the space
because of the lack of Gravitational force, which also proves
that your weight in Earth and in Mercury will be different.
Venus:
▪ The surface of the Venus is full of volcanoes and damaged
mountains.

6. ▪ One year in Venus is 225 Earth days.
▪ It traps heat in the thick atmosphere making it the hottest
planets in our Solar System. The Planet’s surface temperature
is about 465 C.
Earth:
▪ The Earth is the only planet in the Solar System that is known to
consist of living things and organisms.
▪ Earth’s atmosphere consists of 78% nitrogen, 21% oxygen and
1% others.
▪ Earth has a moon known as Luna that orbits around the Earth.
Contd…

7. Mars:
▪ Mars makes a complete orbit around the sun in 687 Earth days.
▪ It has a thin atmosphere which mostly consists of Carbon
dioxide, Nitrogen and Argon.
▪ Mars has 2 moons, which are Phobos and Deimos.
Jupiter:
▪ Jupiter is twice as bigger as all the other planets combined.
▪ It is a gas giant because it lacks a solid surface like Earth.
▪ It takes 12 Earth years to complete it’s orbit around the Sun.
Contd…

8. Contd…
Saturn:
▪ Saturn has 7 rings and division/gaps in between them.
▪ It takes 29 Earth years to complete it’s orbit around the Sun.
▪ It is the most least dense planet in our solar system.
Uranus:
▪ It takes 84 Earth years to complete it’s orbit around the Sun.
▪ It is called the “Ice Giant” because of it being extremely cold and
not having a solid surface.
▪ It has 13 rings which are made of dust particles and large rocks.

9. Contd…
Neptune:
▪ Neptune takes 165 Earth years to complete it’s orbit around the
Sun.
▪ The 6 rings that circle the planet are irregular compared to the
rings in the other planets.
▪ Neptune’s atmosphere is mainly made up of Hydrogen, Helium
and Methane.

10. Content Layout
▪ The Solar System and Space
▪ Days, Nights and Years
▪ The Seasons
▪ The Phases of the Moon
▪ Comets and Meteors and Asteroids
The Earth And Beyond

11. The Earth days andYears
How many hours is a day?
24 Hours
How many days is a Year?
365 ¼ Days
365 days 6 hours
Shape of the Earth?
It is nearly a sphere.

12. Day and Night
In this part, it is Night
In this part, it is day.
Sun
This is because the Earth rotates on its
axis anti-clockwise as it orbits the Sun.

13. Content Layout
▪ The Solar System and Space
▪ Days, Nights and Years
▪ The Seasons
▪ The Phases of the Moon
▪ Comets and Meteors and Asteroids
The Earth And Beyond

14. What caused the Earth’s seasons?
▪ The Earth rotates about its axis which is tilted at an angle of
23.5 degrees.
▪ As the Earth orbits the Sun, when its axis tips towards the Sun,
the weather gets warmer. When it tips away, the weather gets
colder, causing the Earth’s Seasons.
▪ When the North pole tilts towards the Sun. It is summer in the
Northern Hemisphere. At the same time it is winter in the
Southern Hemisphere.
▪ When the North pole is now tilted away from the Sun. It is winter
in the Northern Hemisphere. At the same time it is summer in
the Southern Hemisphere.

15. Northern Hemisphere

16. Equinox and Solstice
▪ The longest day of the year in the North is June 21st – we call it
the Summer Solstice.
▪ The shortest day and longest night of the year in the north is
December 21st – we call it the Winter Solstice.
▪ There are 2 days in the year when the duration of the night and
day are equal(12 hours):
Fall Equinox: September 21st
Spring Equinox: March 21st

17. Content Layout
▪ The Solar System and Space
▪ Days, Nights and Years
▪ The Seasons
▪ The Phases of the Moon
▪ Comets and Meteors and Asteroids
The Earth And Beyond

18. The Phases of The Moon

19. Explanation
New Moon: This is when the moon is directly in between the Sun
and the Earth. This means the part of the moon being lit up by the
sun is facing away from the earth causing us to see no moon on that
day.
Crescent Moon: This is when some part of the moon that is being lit
up is facing towards the Sun causing us to see a Crescent Moon.
Half Moon: This occurs when half of the moon being lit up by the sun
is facing towards the Earth causing us to see a Half moon.
Gibbous Moon: This occurs when most of the moon that is being lit
up is facing towards the Earth causing us to see a Gibbous Moon.
Full Moon: This occurs when the whole moon being lit up is facing
towards the earth causing us to see a Full Moon.

20. Content Layout
▪ The Solar System and Space
▪ Days, Nights and Years
▪ The Seasons
▪ The Phases of the Moon
▪ Comets and Meteors and Asteroids
The Earth And Beyond

21. Comets
▪ Comets are icy celestial bodies that release gas or dust.
▪ They consist of ice, ammonia, carbon dioxide, dust, methane
etc.
▪ They come from the Kuiper Belt and Oort cloud.
▪ It is described as a dirty snowball.
Halley’s Comet

22. Meteors
▪ Meteors(“shooting stars”) are big chunks of rock or dust that
enter a planet’s atmosphere and burn up to become Meteors.
▪ They can be seen in a clear night sky as small trails of light.
They last for less than a second. The best time to view these
Meteors is during periodic showers.
▪ Sometimes, the piece of rock can be big enough and may not all
burn up entering the atmosphere and it may hit the ground.
Such shooting stars are called meteorites.
▪ Meteors, which fly through the atmosphere, when in space they
are called meteoroids and when they hit the ground are called
meteorites.

23. Asteroids
▪ An asteroid is a chunk of rock and metal in the outer space.
▪ Most of them are located in the Asteroid Belt that lies between
the orbits of Mars and Jupiter and these asteroids also move in
an orbit around the Sun.
3 types:
▪ Carbon: These asteroids are mostly made up of carbon. These
make up 75% of all asteroids.
▪ Stony: These asteroids are made up of mostly of rock and some
metal.
▪ Metallic: These Asteroids are made of mostly metals, mostly
iron and nickel.

24. Asteroid Belt

25. Bibliography
▪ https://axischange.files.wordpress.com/2017/08/2-asteroid-belt.jpg?w=660&h=413
▪ https://solarsystem.nasa.gov/planets/neptune/overview/
▪ https://kidsastronomy.com/solar-system/neptune/
▪ http://bestanimations.com/Earth&Space/Earth/earth-spinning-rotating-animation-54.gif
▪ http://www.bbc.co.uk/staticarchive/b688bbf989b69fda2f29368bee81826a7b386ed9.gif
▪ https://www.davidreneke.com/wp-content/uploads/2011/12/Monphase.jpg
▪ https://vignette.wikia.nocookie.net/theoretical-physics-digest/images/2/2f/Parts-of-a-
comet.jpg/revision/latest?cb=20151021123102
▪ http://www.esa.int/esaKIDSen/SEMMIDEWPJH_OurUniverse_0.html
▪ https://www.ducksters.com/science/physics/asteroids.php
▪ https://hostway.com/wp-content/uploads/2017/07/giphy-downsized-6-1.gif