Class Sky
This class represents a set of sky coordinates.
If the data was the result of a coordinate transformation, the
corresponding time is stored in addition. A function to convert
to local coordinates is included.
Defined in: Sky.js.
| Constructor Attributes | Constructor Name and Description |
|---|---|
|
Sky(rightAscension, declination)
|
| Field Attributes | Field Name and Description |
|---|---|
| <constant> |
Declination in degrees
|
| <constant> |
Right ascension in hours
|
| <constant> |
Time corresponding to ra and dec if they are the result of
a conversion.
|
| Method Attributes | Method Name and Description |
|---|---|
| <static> |
Sky.dist(sky1, sky2)
Calculate the distance between two sky positions.
|
|
toLocal(time)
Convert sky coordinates to celestial coordinates.
|
Class Detail
Sky(rightAscension, declination)
Author: Thomas Bretz.
var sky = new Sky(12, 45);
var local = sky.toLocal();
- Parameters:
- {Number} rightAscension
- Right ascension in hours
- {Number} declination
- Declination in degree
Field Detail
<constant>
{Number}
dec
Declination in degrees
<constant>
{Number}
ra
Right ascension in hours
<constant>
{Date}
time
Time corresponding to ra and dec if they are the result of
a conversion.
Method Detail
<static>
{Number}
Sky.dist(sky1, sky2)
Calculate the distance between two sky positions.
The distance between the two provided objects is calculated.
The returned value is an absolute distance (angle) between
the two positions.
- Parameters:
- {Sky} sky1
- Celestial coordinates for one of the two objects for which the distance on the sky should be calculated. In principle every object with the properties 'ra' and 'dec' can be provided.
- {Sky} sky2
- Celestial coordinates for one of the two objects for which the distance on the sky should be calculated. In principle every object with the properties 'ra' and 'dec' can be provided.
- Returns:
- {Number} Absolute distance between both positions on the sky in degrees.
{Local}
toLocal(time)
Convert sky coordinates to celestial coordinates.
As observatory location the FACT telescope is assumed.
The conversion is done using libnova's ln_get_hrz_from_equ.
- Parameters:
- {Date} time Optional, Default: new Date()
- Reference time for the converstion.
- Returns:
- A Local object with the converted coordinates and the conversion time.