Space Science with Python #9 to #11 — Coordinate Systems
Coordinate systems are essential in astronomy; yet for beginners difficult to grasp. A 3-dimensional, astro-dynamically chaotic world is surrounding us; so let’s introduce some reference frames to put everything in order!
Is the title image familiar to you? Did you use (recently) an analogue map for navigation? Thanks to miscellaneous apps and GPS this may not be required anymore; but if you like hiking in remote places a classic map, compass and other tools are still essential. One’s position on our blue planet can easily be defined using the so-called geographic longitude and latitude.
In astronomy and space science things are similar, but a little bit more complicated. There are several coordinate systems, depending on the scientific context. Let’s take a look at 3 of them:
- Equatorial Coordinate System: An “Earth-centric” coordinate system that “rotates” with the Earth, allowing one to map objects in the sky in a time-stateless manner
- Ecliptic Coordinate System: A system that is mostly used for Solar System research. The “north pole” points perpendicular to the Ecliptic Plane (an imaginary plane drawn by the Earth’s movement around the Sun) and the “X-Axis” aims towards the vernal equinox of our home planet.
- Horizontal Coordinate System: A … not so commonly used system that is dependent on one’s location. The Zenith is the “top” of the coordinate system and the cardinal points are used to align the latitude lines. Anyway, this system is not used in a scientific context; though it is helpful to determine location specific events like e.g., the time of the sunrise or sunset.
All 3 coordinate systems are covered in my 3 corresponding Space Science with Python tutorials. Each coordinate system is being covered by a Jupyter Notebook and YouTube video with some more explanations.
Though, the last video about the Horizontal Coordinate System covers only how to compute the horizon … but still … useful in some sense.
The notebooks can be found here:
The corresponding videos:
Stay curious and until next time,
Thomas
P.S.: do not forget to subscribe to my YouTube channel. I upload Space Science with Python video on a weekly basis and any support is welcome
