Did a workshop on celestial navigation today. Used a sextant from Freiberg, as old AS me. #navigation #sextant

I decided I should really put the #celestial #navigation course I took a few years ago into practice, so started looking online for a second hand #sextant.
One eBay ad looked promising, I got all keen, but when I asked for some more photos (as I thought I could make out some corrosion - actual furriness on a polished aluminium part) it was taken down. A narrow escape on my part, the search continues.

Hey Mastodon, I don’t suppose anyone’s got a decent sextant for sale?

@rachel

So that is the story of how I happened to acquire a modern #sextant for only $12.

When I came home and could browse the Internet (this was long before I had data access on my phone), I discovered that yes, it was missing a tube or scope at the eyepiece section, but was otherwise complete.

I have been either busy or ill since acquiring it but do fully intend and expect to play around with it one of these days.

But I still laugh at myself for my brain being so misled by the sextant's material (dark plastic) and my general unfamiliarity with the devices (on the #landlocked #prairies ).

Clearly the charity store didn't recognise it either, or I'm sure it wouldn't have been casually tossed among miscellanea for $5, but behind glass at a rather higher price. 😂

Best of luck to you on your quest to borrow a sextant! 🙂❤️

8/fin

@rachel

I decided to buy it. It was less than $5 #Canadian so not a big deal for an impulse purchase.

A few minutes later I came across the #sextant's box, complete with a carved-#foam interior, so old that the foam was starting to crumble to dust.

The box was priced separately, at something like $12.

When I went to the cashier, I showed that the two items clearly belonged together and could I get a discount on them as a single item? The manager let me have both for the price of the box.

7/x

@rachel

Again, I live nowhere near a sea or ocean. I've never seen an actual #sextant in real life, just ones in movies or illustrations.

And those sextants were always shiny #brass, not #plastic!

But now that I understood the object's purpose, I also realised that #plastic was an excellent #medium for using in a #boat or #ship: it won't rust or corrode from #water or #salt.

6/x

@rachel

A pendulum! This jogs my brain to an apparently-random #memory, likely from #JamesBurke's #TheDayTheUniverseChanged series, about how #latitude was easy to determine via the skies, but that #longitude could not be measured until timepieces that did NOT require a #pendulum to drive it were invented.

Pendulum movement isn't very functional on a rolling #ship, after all.

And at that moment, the name of the item
I held and it's purpose snapped vividly to mind: it was a #sextant!

5/x

@rachel

Alas distance makes it impossible for me to help you, but hilariously I -- someone in the middle of the #Canadian #prairies with zero access to sea or ocean, DO happen to have a #sextant.

The story of this is amusing (IMO) so please bear with me while I share. 🙂

So one day I'm at a chain #charity #secondhand goods store (#ValueVillage, in particular) and I find this weird triangular-ish item randomly among the less-categorised items.

At first I assume it is a toy: I don't keep up with modern kids' #TV or #film franchises but it looks like the sort of weird item that might get designed as some sort of #alien #weapon, especially as it was made of very dark plastic.

1/x

@rachel

Unfortunately, you are on the wrong side of the planet to loan you my sad Davis Mark 3 practice sextant!

For a while 15 years ago, I was shooting the sun from my back yard, using a pan of water as an artificial horizon, getting twice the real elevation.

Then using an ephemeris to see where the sun was directly overhead, and calculating how far away my position must be...

Do you think you could find a #sextant to borrow locally?

Perhaps with a navigator to teach its use?

@rachel maybe some tags will connect your request to the right audience. :)

#sextant #sailing #navigation #instruments

Today I found a #sextant in a #charityshop

All I need now is a boat

6/ Diese fundamentale Messung war bereits in der Antike bekannt. Das Prinzip dieser Messung wurde durch weitere Werkzeuge wie das #Astrolabium, den #Oktant und den #Sextant perfektioniert. Die Bestimmung des #Längengrads ist ungleich schwieriger. Erste exakte Messungen gelangen erst im 18. Jh.

#meermay #mermay #sextant #mermay2025 #abstract

@hoernchen72 @Luftgaengerin deswegen ja der #Sextant, funktioniert natürlich vorzüglich. Leider habe ich drei Arme zu wenig, um das Objektiv dahinter zu halten.
#sonnenfinsternis

#sonnenfinsternis 1. Kontakt gesichtet, mit #Sextant und Schattengläsern.
#Bonn #BadGodesberg

@hoernchen72 @Luftgaengerin habt ihr einen #Sextant a n Bord?
https://sunsetsunrisetime.com/sun-eclipse/enkhuizen
#sonnenfinsternis

historické vědecké přístroje - #sextant / #historical #scientific #instruments - sextant
Astronomická věž Klementina - interiér / Clementinum Astronomical tower - interior
#Klementinum
https://www.flickr.com/photos/96541566@N06/54352900954/
#Czechia #Prague #science #history #navigation #astronomy

Navigating the high seas means precision is everything! 🌊 So, I created a Python script to filter my sextant readings on my #YachtmasterOcean passage from the Azores to Fernando de Noronha 🧭✨ Say goodbye to outliers and hello to a clean average! Now I can trust my stars (and my code) just a little bit more. Check it out here: https://github.com/kevinveenbirkenbach/sextant-averager #CelestialNavigation #Python #Sextant #OceanPassage #Sailing #Navigation #Yachtmaster

Wanted to make a reference to using a sextant after reading this article. Then realized I have no idea how sextants work and then went down a rabbit hole of learning.

https://www.cbc.ca/news/world/gps-interference-airlines-1.7213538

#gps #sextant #navigation

Pause
zur Entspannung

Was hat das ALLES mit Sternen und Amerika zu tun

Eine mögliche SICHT spätere ZEITEN der #Schiffsnavigation
Planet ERDE
Meer und Ozean

#Sextant Navigation

HEUTE noch Teil der Captain und Brücke Ausbildung global
Planet ERDE

Astronomie
Marine
Navigation
Sternwarten
Erfindung vor GPS (das bekanntlich abgeschaltet werden kann - als Satellit DIENST)
usw.
Sterne DEUTEN