diff --git a/lib/main.rb b/lib/main.rb
new file mode 100644
index 00000000..ec5afd46
--- /dev/null
+++ b/lib/main.rb
@@ -0,0 +1,51 @@
+require_relative "planet.rb"
+require_relative "solar_system.rb"
+
+def main
+
+  #Added planets' info to each planet instance
+  solar_system = SolarSystem.new("Sun")
+
+  earth = Planet.new("Earth", "blue-green", 5.972e24, 1.496e8, "Only planet known to support life")
+  solar_system.add_planet(earth)
+
+  mercury = Planet.new("Mercury", "dark grey", 4.867e24, 5.791e7, "Mercury is the smallest plannet in our solar system")
+  solar_system.add_planet(mercury)
+
+  neptune = Planet.new("Neptune", "purple", 1.024e26, 4.495e9, "It is four times wider than Earth")
+  solar_system.add_planet(neptune)
+
+  saturn = Planet.new("Saturn", "yellowish-brown", 5.683e26, 1.434e9, "Saturn is the second largest planet in our solar system")
+  solar_system.add_planet(saturn)
+
+  venus = Planet.new("Venus", "opal", 4.867e24, 1.082e8, "It has intense heat and volcanic activity")
+  solar_system.add_planet(venus)
+
+  ######## Prompt User's inputs########
+
+  puts "Welcome to Solar System program!"
+  puts "What would you like to do?"
+  puts "[list planets] [planet details] [add planet] [exit]"
+  user_input = gets.chomp
+
+  until user_input.downcase == "exit"
+    case user_input.downcase
+    when "list planets"
+      puts solar_system.list_planets
+    when "planet details"
+      puts "Which planet would you like to learn about?"
+      planet_details_input = gets.chomp
+      found_planet = solar_system.find_planet_by_name(planet_details_input.downcase)
+      puts found_planet.summary
+    when "add planet"
+      solar_system.user_added_planet
+      puts solar_system.list_planets
+    end
+
+    puts "What would you like to do next?"
+    puts "[list planets] [planet details] [add planet] [exit]"
+    user_input = gets.chomp
+  end
+end
+
+main
diff --git a/lib/planet.rb b/lib/planet.rb
new file mode 100644
index 00000000..72415dff
--- /dev/null
+++ b/lib/planet.rb
@@ -0,0 +1,15 @@
+class Planet
+  attr_reader :name, :color, :mass_kg, :distance_from_sun_km, :fun_fact
+
+  def initialize(name, color, mass_kg, distance_from_sun_km, fun_fact)
+    @name = name
+    @color = color
+    @mass_kg = mass_kg
+    @distance_from_sun_km = distance_from_sun_km
+    @fun_fact = fun_fact
+  end
+
+  def summary
+    return "Planet #{name} has the color of #{color} with the mass of #{mass_kg} kgs. This planet is #{distance_from_sun_km} km from the sun. A fun-fact about this planet is: #{fun_fact}"
+  end
+end
diff --git a/lib/solar_system.rb b/lib/solar_system.rb
new file mode 100644
index 00000000..a863f718
--- /dev/null
+++ b/lib/solar_system.rb
@@ -0,0 +1,47 @@
+
+class SolarSystem
+  attr_reader :star_name, :planet
+
+  def initialize(star_name)
+    @star_name = star_name
+    @planets = []
+  end
+
+  def add_planet(planet_instance)
+    @planets << planet_instance
+  end
+
+  def list_planets
+    conclusion_statement = "Planets orbiting #{star_name}:\n"
+
+    i = 1
+    planet_list = ""
+    @planets.each do |planet|
+      planet_list += "#{i}.#{planet.name} \n"
+      i += 1
+    end
+
+    return conclusion_statement + planet_list
+  end
+
+  def find_planet_by_name(planet_name)
+    @planets.find { |planet| planet.name.downcase == planet_name.downcase }
+  end
+
+  def user_added_planet
+    puts "Please enter new planet's name"
+    planet_name = gets.chomp
+    puts "Please enter new planet's color"
+    planet_color = gets.chomp
+    puts "Please enter new planet's mass in kilograms"
+    planet_mass = gets.chomp.to_i
+    puts "Please enter the distance between this new planet and the sun"
+    planet_distance = gets.chomp.to_i
+    puts "Please enter new planet's fun_fact"
+    fun_fact = gets.chomp
+
+    user_planet = Planet.new(planet_name.capitalize, planet_color, planet_mass, planet_distance, fun_fact)
+
+    add_planet(user_planet)
+  end
+end
diff --git a/specs/planet_spec.rb b/specs/planet_spec.rb
new file mode 100644
index 00000000..dbc3307d
--- /dev/null
+++ b/specs/planet_spec.rb
@@ -0,0 +1,11 @@
+require "minitest/autorun"
+require "minitest/reporters"
+require_relative "../lib/planet.rb"
+Minitest::Reporters.use!
+
+describe "planet" do
+  it "Check if a new instance is an instance of class Planet " do
+    earth = Planet.new("Earth", "blue-green", 5.972e24, 1.496e8, "Only planet known to support life")
+    expect(earth).must_be_instance_of Planet
+  end
+end