Class: Astronoby::Body

Inherits:
Object
  • Object
show all
Defined in:
lib/astronoby/body.rb

Instance Method Summary collapse

Constructor Details

#initialize(equatorial_coordinates) ⇒ Body

Returns a new instance of Body.



5
6
7
 
# File 'lib/astronoby/body.rb', line 5

def initialize(equatorial_coordinates)
  @equatorial_coordinates = equatorial_coordinates
end

Instance Method Details

#rising_azimuth(latitude:) ⇒ Object

Source:

Title: Celestial Calculations
Author: J. L. Lawrence
Edition: MIT Press
Chapter: 5 - Stars in the Nighttime Sky



30
31
32
33
34
35
 
# File 'lib/astronoby/body.rb', line 30

def rising_azimuth(latitude:)
  ar = azimuth_component(latitude: latitude)
  return nil if ar >= 1

  Angle.acos(ar)
end

#rising_time(latitude:, longitude:, date:) ⇒ Object

Source:

Title: Celestial Calculations
Author: J. L. Lawrence
Edition: MIT Press
Chapter: 5 - Stars in the Nighttime Sky



14
15
16
17
18
19
20
21
22
23
 
# File 'lib/astronoby/body.rb', line 14

def rising_time(latitude:, longitude:, date:)
  h2_component = h2(latitude: latitude)
  return nil if h2_component.nil?

  rising_lst = 24 +
    @equatorial_coordinates.right_ascension.hours - h2_component.degrees
  rising_lst -= 24 if rising_lst > 24

  Util::Time.lst_to_ut(date: date, longitude: longitude, lst: rising_lst)
end

#setting_azimuth(latitude:) ⇒ Object

Source:

Title: Celestial Calculations
Author: J. L. Lawrence
Edition: MIT Press
Chapter: 5 - Stars in the Nighttime Sky



57
58
59
60
61
62
 
# File 'lib/astronoby/body.rb', line 57

def setting_azimuth(latitude:)
  rising_az = rising_azimuth(latitude: latitude)
  return nil if rising_az.nil?

  Angle.as_degrees(360 - rising_az.degrees)
end

#setting_time(latitude:, longitude:, date:) ⇒ Object

Source:

Title: Celestial Calculations
Author: J. L. Lawrence
Edition: MIT Press
Chapter: 5 - Stars in the Nighttime Sky



42
43
44
45
46
47
48
49
50
 
# File 'lib/astronoby/body.rb', line 42

def setting_time(latitude:, longitude:, date:)
  h2_component = h2(latitude: latitude)
  return nil if h2_component.nil?

  setting_lst = @equatorial_coordinates.right_ascension.hours + h2_component.degrees
  setting_lst -= 24 if setting_lst > 24

  Util::Time.lst_to_ut(date: date, longitude: longitude, lst: setting_lst)
end