diff --git a/Grade 9/Science/SNC1DZ/Unit_5_Astronomy_Study_Sheet.md b/Grade 9/Science/SNC1DZ/Unit_5_Astronomy_Study_Sheet.md
index e69de29..a1abbea 100644
--- a/Grade 9/Science/SNC1DZ/Unit_5_Astronomy_Study_Sheet.md
+++ b/Grade 9/Science/SNC1DZ/Unit_5_Astronomy_Study_Sheet.md
@@ -0,0 +1,73 @@
+# Unit 5: Astronomy
+
+## Suns Affect on Earth
+
+### The Aurora Borealis (Northern Lights)
+- The `Northern Lights` are the result of collisions between gaseous particles in the Earth's atmosphere with charged particles released from the sun's atmosphere.
+- `Solar winds` travelling toward Earth follow the lines of `magnetic force` created by Earth’s magnetic field (which is strongest near the **NORTH** and **SOUTH** `poles`).
+- Near the poles, they come in contact with particles in Earth’s atmosphere, producing a display of `light` in the night sky.
+- `Northern Lights` = `Aurora Borealis`.
+- `Southern Lights` = `Aurora Australis`.
+
+## The Solar System
+
+
+
+### Planets
+1. A planet must orbit a star
+2. A planet must be big enough for its gravity to pull into a round shape
+3. It must be big enough to clear most asteroids out of its path for its orbit.
+- If they can't do these things, it's not a planet, it's a dwarf planet.
+
+### Drawf Planets
+- A celestial object that orbits the Sun and has a spherical shape but **does not** dominate its orbit.
+- Ceres, Pluto, Haumea, Makemake, and Eris
+- `Pluto’s` tilted orbit crosses Neptune’s orbit
+- 
+
+### The Inner Planets
+- Mercury, Venus, Earth & Mars.
+- Small rocky planets.
+- Located between the `Sun` and `Asteroid Belt`.
+
+|Planet|Orbital Period|Rotation|Atmosphere|Temperature|Number of Moons|Rings?|Unique Characteristics|
+|:-----|:-------------|:-------|:---------|:----------|:---------|:----|:---------------------|
+|Mercury|88 days|59 days|None|180 to 400oC|0|No|- No atmosphere to trap heat
- Contains craters
- Rarely visible in our night sky because its is so close to the sun|
+|Venus|224.7 days|243 days, `(Opposite rotation)`|Carbon dioxide, nitrogen|462oC|0|No|- Brightest object in the sky after the Sun & Moon|
+|Earth|365.26 days|24 hours|Nitrogen, Oxygen|-88 to 58oC|1|No|- Ozone filters some of the damaging radiation from the Sun
- Temperatures are constant
- 70% of planet's surface is water|
+|Mars|687 days|24.65 hours|Carbon dioxide, Nitrogen|-90 to -5oC|2|No|- Called the `red planet` due to its rusty soil
- Very dry
- Once had volcanoes, glaciers, & water|
+
+### The Outer Planets
+- Jupiter, Saturn, Uranus, Neptune
+- `Large`, composed of `gas`.
+- Atopsheres consist mainlyof the gases `hydrogen` and `helium`.
+
+|Planet|Orbital Period|Rotation|Atmosphere|Temperature|Number of Moons|Rings?|Unique Characteristics|
+|:-----|:-------------|:-------|:---------|:----------|:---------|:----|:---------------------|
+|Jupiter|11.9 years|9.85 hours|Hydrogen, Helium, methane|-148oC|63|Yes|- Largest planet (11x the diameter of the Earth)
- Features are its coloured bands, the Great Red Spot & hurricanes
- Orbiting rings of rocks|
+|Saturn|29.5 years|10.65 hours|Hydrogen, Helium, Methane|-178oC|60|Yes|- Second largest, no solid core
- Cloudy & windy, over 1000 separate rings|
+|Uranus|84.1 years|17.3 hours `(on its side)`|Hydrogen, Helium, Methane|-216oC|27|Yes|- Winds blow up to 500km/h|
+|Neptune|164.8 years|15.7 hours|Hydrogen, Helium, Methane|-214oC|13|Yes|- Uneven orbit, Bright blue & white clouds
- Has a dark region called the Great Dark Spot, which appears to be the center of a storm|
+
+### Asteroids
+- They are composed of rock & metal.
+- Although they orbit the Sun, they are too small to be considered planets.
+- Most asteroids lie in the asteroid belt, located between Mars & Jupiter.
+- A **`meteroid`** is a piece of metal or rock that is `smaller` than an asteroid.
+- Sometimes a meteroid get pulled in by `Earth's gravity`. They `burn` up in the Earth's `atmosphere`, creating a bright streak of `light` across the sky, know as **`meteor`** (shooting star).
+- Larger meteors do not burn up completely in the atmosphere and their `remains`, which we call **`meteorites`**, crash to the ground.
+- 
+
+### Asteroid Belt
+- 700,000 to 1.7 million asteroids with a diameter of 1 km or more.
+- Over 200 asteroids are known to be larger than 100 km.
+- 
+
+### Comets
+- **`Comets`** are large chunks of `ice, dust`, and `rock` that orbit the Sun.
+- As a comet approaches the Sun, radiation and solar wind from the Sun, causes a `gaseous tail` to form, `pointing` directly `away` from the Sun.
+- A `dust` tail forms in the direction from which the comet originated.
+- Most comets have 2 tails;
+ - `gaseous tail`
+ - `dust tail`
+- 
\ No newline at end of file