Class: Astronoby::DeepSkyObject

Inherits:

Object

• Object
• Astronoby::DeepSkyObject

Includes:

Body

Defined in:

lib/astronoby/bodies/deep_sky_object.rb

Overview

Represents a deep-sky object (star, galaxy, nebula, etc.) with optional proper motion and parallax data.

Instance Method Summary

• #at(instant, ephem: nil) ⇒ Astronoby::DeepSkyObjectPosition

  Position of the deep-sky object at the given instant.

• #initialize(equatorial_coordinates:, proper_motion_ra: nil, proper_motion_dec: nil, parallax: nil, radial_velocity: nil) ⇒ DeepSkyObject constructor

  A new instance of DeepSkyObject.

Constructor Details

#initialize(equatorial_coordinates:, proper_motion_ra: nil, proper_motion_dec: nil, parallax: nil, radial_velocity: nil) ⇒ DeepSkyObject

Returns a new instance of DeepSkyObject.

Parameters:

• equatorial_coordinates (Astronoby::Coordinates::Equatorial) —

  Equatorial coordinates at epoch J2000.0

• proper_motion_ra (Astronoby::AngularVelocity, nil) (defaults to: nil) —

  Proper motion in right ascension

• proper_motion_dec (Astronoby::AngularVelocity, nil) (defaults to: nil) —

  Proper motion in declination

• parallax (Astronoby::Angle, nil) (defaults to: nil) —

  Parallax angle

• radial_velocity (Astronoby::Velocity, nil) (defaults to: nil) —

  Radial velocity

# File 'lib/astronoby/bodies/deep_sky_object.rb', line 17

def initialize(
  equatorial_coordinates:,
  proper_motion_ra: nil,
  proper_motion_dec: nil,
  parallax: nil,
  radial_velocity: nil
)
  @initial_equatorial_coordinates = equatorial_coordinates
  @proper_motion_ra = proper_motion_ra
  @proper_motion_dec = proper_motion_dec
  @parallax = parallax
  @radial_velocity = radial_velocity
end

Instance Method Details

#at(instant, ephem: nil) ⇒ Astronoby::DeepSkyObjectPosition

Returns Position of the deep-sky object at the given instant.

Parameters:

• instant (Astronoby::Instant) —

  Instant of the observation

• ephem (Astronoby::Ephemeris, nil) (defaults to: nil) —

  Ephemeris to use for Earth position calculation

Returns:

• (Astronoby::DeepSkyObjectPosition) —

  Position of the deep-sky object at the given instant

# File 'lib/astronoby/bodies/deep_sky_object.rb', line 36

def at(instant, ephem: nil)
  DeepSkyObjectPosition.new(
    instant: instant,
    equatorial_coordinates: @initial_equatorial_coordinates,
    ephem: ephem,
    proper_motion_ra: @proper_motion_ra,
    proper_motion_dec: @proper_motion_dec,
    parallax: @parallax,
    radial_velocity: @radial_velocity,
    deep_sky_object: self
  )
end