ASA 107, Celestial Navigation
Earn your official ASA 107 certification by completing this online course from Starpath. This course teaches the ability to determine your position at sea using timed sextant sights of the sun, moon, stars, and planets as well as other routine procedures to ensure safe and efficient offshore navigation.
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Course OVERVIEW
Celestial navigation is a valuable skill for any sailor who wants to sail offshore or in remote areas where electronic navigation devices may not work or be available. ASA 107, Celestial Navigation is a comprehensive course that covers the theory and practice of celestial navigation for safe navigation of a sailing vessel in offshore waters.
Gain confidence and self-reliance as a mariner and prepare yourself to explore new horizons by learning to navigate and find your location in open waters based on your location in relation to the sun, moon, stars and planets. Plus, learn other crucial factors imperative to offshore navigation, such as logbook procedures, dead reckoning, error analysis, route planning, etc. A prerequisite for ASA 108, Offshore Passage Making, this online course will cover the following topics:
» SEXTANTS.
An extensive overview of Sextants and their use, purpose and care:
An overview of a Noon sights for latitude, including details, virtues, and drawbacks:
The role of plotting and "chart work" in celestial navigation:
The role of sun (sunrise, sunset and twighlight times) in ocean navigation:
The role of star, planet and moon sights and step by step procedures for sight reduction:
The role of star ID in routine celestial navigation via introduction to The Star Finder Book:
The optimum procedure for running fixes.
An extensive overview of Sextants and their use, purpose and care:
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‣ How to read a Sextant & take a Sextant Sight (including Plastic Sextants)
‣ Introduction to sextant corrections
‣ How to check a Sextant with the stars
An overview of a Noon sights for latitude, including details, virtues, and drawbacks:
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‣ Step-by-step procedures for doing a LAN Sight
‣ Deciphering Longitude from LAN
‣ Calculate the zone time given longitude
‣ Convert standard time and zone time to GMT and vice versa
The role of plotting and "chart work" in celestial navigation:
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‣ Universal Plotting Sheets & Route Planning
‣ Electronic Navigation at Sea (GPS)
‣ Radio Time Signals & High Sea Radio Usage
‣ Compass Checks at Sea - Convert True Bearing to Determine Error & Deviation
‣ Procedure for Plotting Celestial LOPs - Convert Longitude into Time
‣ Latitude by Polaris
‣ Artificial Horizons - apply corrections for index error, dip of the horizon, and total correction to find true altitudes
‣ Emergency navigation techniques and notes on the latest developments in GPS
The role of sun (sunrise, sunset and twighlight times) in ocean navigation:
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‣ Use of the Nautical Almanac for finding the sun's declination
‣ Determining Sun Lines using the Nautical Almanac
‣ Use of Sight Reduction Tables
‣ Checking Index Correction with the sun ("Explorer's method")
‣ Calculate the time of meridian passage of the sun and calculate the boat’s latitude
‣ Calculate the times (ship’s and GMT) of sunrise, sunset and twilight.
‣ Determine the latitude at twilight by means of the Pole Star.
The role of star, planet and moon sights and step by step procedures for sight reduction:
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‣ How to Average Sights for Optimum
‣ Calculate and plot the lines of position obtained from observations of celestial bodies to find the boat’s position
‣ Sight Reduction with the NAO Tables
The role of star ID in routine celestial navigation via introduction to The Star Finder Book:
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‣ Identify Stars and Planets with the 2102-D Star Finder
‣ Precompute Star Sights by Star Finder and direct sight reduction
‣ Star Gazing as a Navigator (tricks and tips, some mythology, some astronomy)
‣ Finding directions from the stars
The optimum procedure for running fixes.
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‣ Running fixes from the sun to find the boat’s position (sun-run-sun)
COURSE LENGTH & PREREQUISITES
This course requires the student to have already completed ASA 105, Coastal Navigation.
You can reasonably expect to spend approximately 40 to 60 hours on this course, depending on how much optional material you choose to cover. You will have the option to control how much work you do during each session and work at your own pace.
You can reasonably expect to spend approximately 40 to 60 hours on this course, depending on how much optional material you choose to cover. You will have the option to control how much work you do during each session and work at your own pace.
Students who complete the online course and pass the final exam will be awarded an official ASA 107 certification and seal for their logbook.
COURSE ACCESSIBILITY
This course can be accessed from any computer (Windows or Mac) with an internet connection. Course registration includes a complete, self-contained home-study course in printed materials as well as a complete electronic version including additional software resources. Work through the lessons, assignments and quizzes in the interactive online classroom and, when you are away from the computer, study with the printed texts, table sections, and work forms.
With the electronic components, you can take the complete course with you as you travel, or use them as a resource to search specific topics. If you prefer to work on your own without computers, you will have a complete syllabus with practice exercises and answers in the printed materials. For added structure to your training, take part in the online discussions and individual quizzes for each lesson.
With the electronic components, you can take the complete course with you as you travel, or use them as a resource to search specific topics. If you prefer to work on your own without computers, you will have a complete syllabus with practice exercises and answers in the printed materials. For added structure to your training, take part in the online discussions and individual quizzes for each lesson.
COURSE MATERIALS - WHAT'S INCLUDED
COURSE MATERIALS
All necessary materials are provided to complete the online course. The only thing extra you may need are basic plotting tools (parallel rules, dividers and protractor)… not just for this course, but for all of your future navigation underway as well. A sextant is not required to work this course.INSTRUCTORS & DISCUSSION GROUPS
Each Starpath course includes free access to online resources and discussion groups. Starpath has instructors in three different time zones monitoring these groups so, should any question arise, simply post it in the Student Discussion Forum for a quick answer — or search the forum to see if an answer to your question already exists.ASA Certification
A certification & seal for your logbook.1 year access
You have one year to complete the course or request an extension.
Other Starpath Courses

ASA 105
Coastal Navigation
Learn practical navigation on inland and coastal waters, including chart reading, piloting, and more.

ASA 107
Celestial Navigation
Learn practical celestial navigation and other aspects of safe ocean navigation.

ASA 117
Basic Celestial Endorsement
Learn to apply basic celestial navigation theory and to determine latitude and longitude at sea.

ASA 119
Marine Weather Endorsement
Learn to observe and forecast weather conditions using traditional maritime skills and modern technology.

ASA 120
Radar Endorsement
Learn to properly use small-craft radar (or radar simulator) for piloting, navigation, and collision avoidance.
ASA & STARPATH ONLINE COURSES
Please register for one or more of the Starpath courses below.
If you have any questions contact support@asa.com
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