Table of Contents

Solar System

From the menu: Setup → Solar system
You can make settings for the Solar system objects in four tabs:

Solar System

In this tab, you can specify the directory with the pictures of the planets. These will be used when you enable the display of planets with the checkbox and click the “Realistic images” radio button by Setup → Solar System → Planet.

You specify to calculate geocentric or topocentric positions. Always keep it to topocentric unless you want to compare the data with a printed ephemeris.
Also you can choose if SkyChart should consider Pluto as a planet or not.

Ephemeris

To give the better possible precision the program use the JPL DExxx ephemeris to compute the planets position and the nutation.
To limit the download size only the file for DE405 between the years 2000 and 2050 is include with the software.

You can add more files to cover an extended time range or to use another ephemeris. Download the binary files from ftp://ssd.jpl.nasa.gov/pub/eph/planets/Linux or ftp://ssd.jpl.nasa.gov/pub/eph/planets/SunOS .
Copy the linx* or unx* files to the installation folder under data\jpleph\ without creating a subdirectory. You must restart the program after you add or remove a file.

The software try to load DE423, DE421, DE405, DE406, DE403, DE200 in this order.
If no file is found for the date it use plan404 by Steve Moshier that allow for computation from -3000 to +3000 with a precision better than one arc second.






Planet

Here you can enable or disable the display of the Sun, planets and satellites on the chart.

Four modes to draw planets are available. You will notice the difference in fields of vision smaller than 2°.

You can also download the free Xplanet software to render realistic planets on your chart.

Check the corresponding box to show a real time image of the Sun from the satellites SDO or SOHO.
Select the image you want from the list. The default AIA 4500 correspond to the visual aspect but you can also try the other wavelengths.
The image will be refresh after the selected time or each time you select another wavelength. Effective update frequency depend on the satellite operation, see the satellite web page for more information. The image source and time is indicated next to the Sun on the map.
This feature require an Internet connection and correct setting of the proxy server if required.

You can update the position of Jupiter's Great Red Spot (GRS) in longitude: Click at the icon at the right to open Jupos page on your browser, where you can find the GRS longitude in the menu at the left. Look at the red dot at the bottom of the graph to get the most recent position of the GRS center. For example it was about 160 in December 2010:

You can check the Show Earth shadow too. When you check this, the position of the Earth shadow will be displayed on the chart as two concentric circles, slightly darker than the background. The dimensions of the circles correspond to the size of the Earth shadow at the distance of the Moon, in order to simulate the lunar eclipses. The core shadow (umbra) is displayed in the middle, around it is the zone of partial eclipse (penumbra).

Transparent line mode allows the stars to be displayed behind planets or the Moon. This can be useful with occultations, to predict where the star will reappear.



Comet

Before SkyCharts can display any comets, you must load a file with the orbital elements of the comets in the database on your computer. The usual way to achieve this, is simply to download the file of the latest version from the Minor Planet Center (MPC). You can also add new comet orbital elements, delete all entries, or selectively delete obsolete entries from the database. There are four tabs in this window:

































Asteroid

Before SkyChart can display asteroids, you need to have a file with the orbital elements of the asteroids. It is quite simple to download the data of the latest version from the Minor Planet Center (MPC) to use in the database on your computer. You can also add new asteroid orbital elements, delete all entries, or selectively remove obsolete entries from your database.

There are five tabs in this window: