Updating comets and asteroids using orbital elements from the Minor Planet Center (MPC)
All downloaded files from the MPC contain the orbital elements of comets and asteroids. Coelix uses these orbital elements (perihelion distance, inclination, semi-major axis, etc.) to calculate ephemerides and the positions of comets and asteroids. These calculations provide very accurate results in most cases.
The orbits of comets and asteroids are easily perturbed by the gravitational pull of the large planets in the solar system, such as Jupiter and Saturn, and even by that of mid-sized planets like Earth. The orbital elements of comets and asteroids, such as eccentricity, inclination, semi-major axis, etc., can be altered when these celestial bodies pass close to the large planets.
Because of this, these orbital elements are only valid for a limited period. For this reason, and because new comets and asteroids are frequently discovered, it is necessary to regularly update the comet and asteroid database in COELIX. Updates are recommended at intervals of two to six months. This will allow the software to generate accurate ephemerides and trajectories for these objects.
All downloaded files from the MPC contain the orbital elements of comets and asteroids. Coelix uses these orbital elements (perihelion distance, inclination, semi-major axis, etc.) to calculate ephemerides and the positions of comets and asteroids. These calculations provide very accurate results in most cases.
The orbits of comets and asteroids are easily perturbed by the gravitational pull of the large planets in the solar system, such as Jupiter and Saturn, and even by that of mid-sized planets like Earth. The orbital elements of comets and asteroids, such as eccentricity, inclination, semi-major axis, etc., can be altered when these celestial bodies pass close to the large planets.
Because of this, these orbital elements are only valid for a limited period. For this reason, and because new comets and asteroids are frequently discovered, it is necessary to regularly update the comet and asteroid database in COELIX. Updates are recommended at intervals of two to six months. This will allow the software to generate accurate ephemerides and trajectories for these objects.
Updating current comets
MPC website
You can access the MPC files containing the orbital elements of comets by clicking the button to the right.
This will open a text-based webpage displaying the list of orbital elements of comets.
Save this list to the main Coelix folder, for example,
C:\CoelixApex, by right-clicking and then using your browser's "Save As..." function, naming the file:
Soft01Cmt.txt.
This will open a text-based webpage displaying the list of orbital elements of comets.
Save this list to the main Coelix folder, for example,
C:\CoelixApex, by right-clicking and then using your browser's "Save As..." function, naming the file:
Soft01Cmt.txt.
If the initial filename is minorplanetcenter.net_iau_Ephemerides_Comets_Soft01Cmt.txt,
keep only the last part of the name, Soft01Cmt.txt, for saving.
All comets in this list are accessible in Coelix to display their ephemerides and positions in sky views, visual fields, and star charts. If a new comet not in the list appears, you can add it to a second list (Favorites) to make it accessible. See the sections below.
keep only the last part of the name, Soft01Cmt.txt, for saving.
All comets in this list are accessible in Coelix to display their ephemerides and positions in sky views, visual fields, and star charts. If a new comet not in the list appears, you can add it to a second list (Favorites) to make it accessible. See the sections below.
NGC7000 H alpha JV
Updating current asteroids
The current asteroids are automatically updated only with each software update. However, these updates only contain the first 50,000 numbered asteroids, and only the first 2,000 are accessible for display in sky views and visual fields. If you want to display other asteroids in Coelix, you must add them yourself to a second list (Favorites). See the following sections.
How to add comets and asteroids to your list of favorites
How to obtain even more precise ephemerides from the JPL HORIZONS System
How to obtain even more precise ephemerides from the JPL HORIZONS System
