mirror of
https://github.com/cosinekitty/astronomy.git
synced 2025-12-30 02:58:42 -05:00
84 lines
3.3 KiB
Markdown
84 lines
3.3 KiB
Markdown
# JavaScript examples for Node.js
|
|
|
|
The source file
|
|
[`astronomy.js`](../../source/js/astronomy.js)
|
|
works as a Node.js module. Download the file into your project directory.
|
|
Then in your own source file, do this:
|
|
|
|
```javascript
|
|
const Astronomy = require('astronomy.js');
|
|
```
|
|
|
|
or install the package with `npm i astronomy-engine` and:
|
|
|
|
```typescript
|
|
import { SearchMoonQuarter } from 'astronomy-engine';
|
|
```
|
|
|
|
 There are no external dependencies!
|
|
Astronomy Engine is completely self-contained, and it always will be.
|
|
|
|
(By the way, you can use the same file `astronomy.browser.js` for
|
|
[astronomy calculations inside the browser](../browser/).)
|
|
|
|
---
|
|
|
|
### [Camera](camera.js)
|
|
Suppose you want to photograph the Moon, and you want to know what it will look like in the photo.
|
|
Given a location on the Earth, and a date/time, this program calculates the orientation of the sunlit
|
|
side of the Moon with respect to the top of your photo image. It assumes the camera faces directly
|
|
toward the Moon's azimuth and tilts upward to its altitude angle above the horizon.
|
|
The angles are defined counterclockwise from the zenith, as shown here:
|
|
|
|
|
|
|
|
### [Culmination](culminate.js)
|
|
Finds when the Sun, Moon, and planets reach their highest position in the sky on a given date,
|
|
as seen by an observer at a specified location on the Earth.
|
|
Culmination is also the moment a body crosses the *meridian*, the imaginary semicircle
|
|
in the sky that passes from due north on the horizon, through the zenith (straight up),
|
|
and then toward due south on the horizon.
|
|
|
|
### [Equator of Date](equator_of_date.js)
|
|
Given the right ascension and declination of a star,
|
|
expressed in J2000 coordinates, converts those coordinates
|
|
to right ascension and declination expressed in the Earth's
|
|
equator at any given date and time. This example illustrates
|
|
how to use rotation matrices to convert one coordinate system
|
|
to another.
|
|
|
|
### [Horizon Intersection](horizon.js)
|
|
This is a more advanced example. It shows how to use coordinate
|
|
transforms to find where the ecliptic intersects with an observer's
|
|
horizon at a given date and time.
|
|
|
|
### [Lunar Eclipse](lunar_eclipse.js)
|
|
Calculates details about the first 10 partial/total lunar eclipses
|
|
after the given date and time.
|
|
|
|
### [Moon Phase Calculator](moonphase.js)
|
|
This example shows how to determine the Moon's current phase,
|
|
and how to predict when the next few quarter phases will occur.
|
|
|
|
### [Positions](positions.js)
|
|
Calculates equatorial and horizontal coordinates of the Sun, Moon, and planets.
|
|
|
|
### [Rise/Set](riseset.js)
|
|
Shows how to calculate sunrise, sunset, moonrise, and moonset times.
|
|
|
|
### [Seasons](seasons.js)
|
|
Calculates the equinoxes and solstices for a given calendar year.
|
|
|
|
### [Triangulate](triangulate.js)
|
|
Given the geographic coordinates of two observers, and angular
|
|
directions they are looking in, determines geographic coordinates
|
|
of the point they are both looking at. This example demonstrates
|
|
use of the geoid functions `VectorObserver` and `ObserverVector`
|
|
that convert between geographic coordinates and vectors.
|
|
|
|
---
|
|
|
|
# [API Reference](../../source/js/)
|
|
Complete documentation for all the functions and types available
|
|
in the JavaScript version of Astronomy Engine.
|