### What is a Zenith and how is a Zenith used in Land Surveying?

In land surveying, the zenith is the point directly above the observer's location. It is the highest point in the sky and can be used as a reference for measuring angles and distances. The zenith is typically identified by a plumb line or a spirit level.

Land surveyors use the zenith in various ways. For example, when measuring the vertical angles between points, they may use the zenith as a reference point to determine the elevation of those points. This is particularly useful when determining the height of tall structures or trees.

In addition, the zenith can also be used to determine the latitude of the observer's location. By measuring the angle between the zenith and the celestial equator (the imaginary line that follows the Earth's equator into space), surveyors can calculate their latitude.

Overall, the zenith is an important reference point for land surveyors, helping them to accurately measure angles, distances, and elevations in their work.

### Did the Ancient Egyptian Surveyors Measure Zenith?

The ancient Egyptians did not have the same tools and technology that we have today to directly measure the zenith. However, they did have a method for determining the approximate zenith point based on observations of the stars.

The Egyptians were skilled astronomers and observed the night sky carefully. They noticed that certain stars appeared to move in a circular pattern around a central point in the sky, which we now know is the North Celestial Pole. By measuring the angle between this point and the horizon, they could estimate the latitude of their location.

To find the zenith, the Egyptians used a plumb line or a weighted string to create a vertical reference line. They then observed the stars and noted the point at which they were directly overhead. This point would correspond to the zenith, which they could then use as a reference for their astronomical observations.

The ancient Egyptians also used the zenith as a reference point for measuring the height of structures such as pyramids and obelisks. They would measure the angle between the top of the structure and the zenith, and use this information to calculate the height.

Overall, while the ancient Egyptians did not have the same tools as modern land surveyors, they were still able to make accurate measurements using careful observations of the stars and other celestial objects.

Survey Legend

Justin Farrow - Creator of Land Surveyors United

You need to be a member of Land Surveyors United - Global Surveying Community to add thoughts!

### Featured Land Surveying Articles

Surveying Articles is a place for members to Share Land Surveying related articles, presentations and knowledge with the Land Surveyors United Community. Post or embed articles for future generations of land surveyors.

### Surveying Articles and Presentations

Do you have an article about Land Surveying that you would like to share?

Land Surveying is a timeless art and science and it is therefore, evergreen! You may also know that a lot of older publications have gone away, unfortunately.   If you have written or published land surveying articles in the past, we would be honored for you to share them here with us.  If it is an older article, you can even republish it here with updates and reflections.

class="block"Tip:   If you published an article in the past on one of the older sites which no longer exist, you can use the Wayback Machine to find it.  Then just copy/paste the old article inside a new post here.  Just be sure to tell us where it was previously posted.

Want to embed a PDF Document?

If you have a PDF document or article related to land surveying that you would like to embed inside an article post, simply copy/paste the following code block into the HTML view of the post editor and replace the BOLD part of the code with the URL of the PDF you'd like to embed.

Code to use:

TIP:  You can also upload your PDF using the file upload button and then copy/paste the URL of the document you uploaded with the BOLD part of the code above to get a flippable PDF like so:

Differences between Forums, Blogs and Article posts

Blog Postsdiffer from Forum posts because you can embed and upload different kinds of information.  Blog posts are best for presenting information and updates for feedback and sharing.  When posting a Blog Post, you can also publish a short excerpt at the bottom which is what most members will see before reading the blog post.  Blog posts are also great for posting new surveying projects and digests of links to multiple surveying topics or your own website.   Things that can be embedded into Blog Posts are videos, images, slideshows, powerpoints, spreadsheets, PDFs, documents and more.

Articles are similar to Blog Posts in all ways except one.  Articles allow for you to post an Author Block at the bottom with links to your contact info, website information, credentials, etc. Similar to Blog Posts, things that can be embedded into Blog Posts are videos, images, slideshows, powerpoints, spreadsheets, PDFs, documents and more.  Similar to both types above, Hub Owners can add article sections and features to any hub they control on the community.

### Surveying Jobs

Representing Land Surveyors in 190 Countries
and all 50 US States. Contribute to your local
chapter and promote Land Surveying globally.

Surveyor Hubs

We have members in every region of the planet. Add
your local Land Surveyor events to the calendar and turn
them into Land Surveyors United Meetups worldwide.

Surveyor Events

Inspire the next generation by contributing
your expertise and experience in Land Surveying
to our 20k+ Surveyor Hive Mind. Mentor the Green!

Mentorship