The options in this window allows you to set how the sky is rendered, what grids and lines are shown, the landscape image to be used and the selection of star lore that specifies the star names and constellations to be displayed.
This tab controls the display of the stars, planets and satellites, atmosphere, labels, and shooting stars.
Relative scale lets you increase or decrease the brightness of stars relative to their magnitudes. For example, if star1 is twice as bright as star 2, changing the values up or down will have an effect on star1 double that of star2.
This option controls how much the stars twinkle.
When enabled this feature reduces the brightness of faint objects when a bright object is in the field of view. This simulates how the eye can be dazzled by a bright object such as the moon, making it harder to see faint stars and galaxies.
This option, when enabled, will simulate the light and darkness during the day and night. If it is disabled, atmospheric effect on seeing is canceled, the sky will be dark and stars with other sky objects will be displayed even during day time.
This options simulates the level of light pollution. Light pollution is the effect of artificial light on seeing the sky objects. The scale used is Bortle Dark-Sky Scale, with1 meaning an excellent dark sky site and 9 a badly light polluted site. It is useful to know what stars is expected to be seen in a particular site.
This option will simulate atmospheric refraction and extinction effects on sky objects. The refraction effect of the atmosphere makes the sun, the moon and stars visible over the horizon before they actually rise or after they actually set. The refraction option will be enabled if the "Show Atmosphere" option is enabled. The rise and set times of sun and moon using this option will be closer to the apparent rise and set time in reality.
Atmospheric refraction is affected by the increase or decrease of pressure and temperature. If you want to closely simulate your current conditions, enter these values in the corresponding fields.
If you want to cancel the refraction effect, set the pressure to 0.
Extinction Coefficient refers to the loss of starlight in passing through Earth atmosphere. If a star is near the horizon its light path through the atmosphere is longer and it will be dimmed more. For excellent mountain top conditions use a value of 0.12, For a good rural site use a value of 0.2 and for murky conditions use 0.35.
If you want to cancel the extinction effect, set the extinction coefficient to 0.
Show planets: Display or hide the solar system objects including the sun and the moon.
Show planet markers: Displays a marking circle around the planet.
Show planet orbits: Displays the orbit path of the planets.
Simulate light speed: Normally, Stellarium shows you the positions of the planets as they are now in space. If you turn this feature on, the delay caused by light propagation will change the apparent positions of the planets. For a good example, toggle this option while zoomed into Jupiter.
Scale Moon: This will increase the size of the Moon for better visibility and to enable clearer Stellarium screen shots of the sky when the Moon is a main object.
Stars: When checked will show stars labels. To show only labels of bright stars keep the button closer to the left and to show labels of dim stars move the button to the right.
Nebulas: When Checked, nebulas will be shown while sliding the button to the right will show dim nebulas and their labels. Nebulas will be hidden if the box is unchecked.
Planets: Planets labels will be shown if this box is checked. The slider button function is unclear for me.
Note that when you zoom in you will see more labels.
Select a value of meteors per hour to simulate a meteor shower with the rate selected.
0: No shooting stars
10: Normal rate
80: Standard Perseids rate
10000: Exceptional Leonids rate
144000: Highest rate ever (1996 Leonids)
Note that this is just a simulation and not a prediction of the density of periodical meteor showers.
A shot of meteor shower simulation
Understanding the sky display is enhanced by various plots of grids, constellation lines, figures and labels.You can also select one among various projection methods to display the sky.
Options are provided to plot different celestial coordinate systems and show lines of special significance.
Equatorial grid will display the lines of the Equatorial coordinate system. The Equatorial coordinate systems functions by projecting the Earth's geographic poles and equator onto the celestial sphere. The projection of the Earth's equator onto the celestial sphere is called the celestial equator. Similarly, the projections of the Earth's north and south geographic poles become the north and south celestial poles, respectively. The lines parallel to the celestial equator describe the declination (Dec), the angle above or below celestial equator while the lines running from north to south describe the right ascension (RA), the angle east of the point of March equinox. This coordinate system is fixed to the sky, meaning a star will have a fixed equatorial coordinates regardless of the time of day or night.
Because of precession, the earth rotation axis is changing which means that the celestial north and south of the Equatorial coordinate system is changing accordingly. For this reasons sky atlases uses a reference time for this coordinate system. J2000 means the Equatorial coordinate system at the year 2000 AD.
This grid will display the lines of the Horizontal coordinate system that uses the observer's local horizon as the fundamental plane. The Altitude is the angle above or below the horizon while the Azimuth is the angle from north increasing towards the east direction.
The Galactic grid will display the lines of the galactic coordinate system (GCS) is a celestial coordinate system which is centered on the Sun and is aligned with the apparent center of the Milky Way galaxy. The "equator" is aligned to the galactic plane. Similar to geographic coordinates, positions in the galactic coordinate system have latitudes and longitudes. The northern galactic pole is located in the constellation of Coma Berenices while the southern pole lies in Sculptor.
The equator line is the line with declination 0° in the equatorial coordinate system. It is a projection on the celestial sphere of the earth equator.
The meridian line is the line with azimuth 0° in the horizontal coordinate system. It is a great circle passing by the north and south points of the local horizon, the north celestial pole and the observer zenith.
The horizon line defines the local horizon of the observer. It is the line with altitude 0°.
The ecliptic line is the line defining the sun apparent path against the stars.
The galactic plane line is the line with zero longitude. It defines the disk plane of the galaxy. You will find it aligned with the milky way.
This option will show or hide the four cardinal points, North, East, South and West.
Lines that define the constellations figure by connecting some of its star members. You can also display the lines through the shortcut key [C] or through the horizontal bar button .
Displays the names of the constellations. You can also display the labels through the shortcut key [V]
Show the boundaries of the constellations as defined by the IAU. This option is applicable to the Western sky culture only.
This option will display the constellation figures as imagined by the respective culture selected from the list under the Star lore tab. You can also display the figures through the shortcut key [R] or through the horizontal bar button
Set the value for the desired brightness of the constellation figures.
Constellation figures, labels, lines and boundaries are displayed
Projection here means the method of representing the celestial sphere on a flat display screen. Different projections exist and each will have some distortion of the real 3D celestial sphere. Stellarium gives you the freedom to select from different types of projections to suit you viewing needs.
Perspective projection keeps the horizon a straight line. The mathematical name for this projection method is gnomonic projection.
Maximum FOV: 120°
The full name of this projection method is, Lambert azimuthal equal-area projection. It preserves the area but not the angle.
Maximum FOV: 360°
Stereographic projection is known since the antiquity and was originally known as the planisphere projection. It preserves the angles at which curves cross each other but it does not preserve area.
Maximum FOV: 235°
In fish-eye projection, or azimuthal equidistant projection, straight lines become curves when they appear a large angular distance from the centre of the field of view (like the distortions seen with very wide angle camera lenses).
Maximum FOV: 180°
The Hammer projection is an equal-area map projection, described by Ernst Hammer in 1892 and directly inspired by the Aitoff projection.
Maximum FOV: 360°
The full name of this projection mode is cylindrical equidistant projection. With this projection all parallels are equally spaced.
Maximum FOV: 233.333°
The mercator projection is one of the most used world map projection. It preserves direction and shapes but distorts size, in an increasing degree away from the equator.
Maximum FOV: 233.333°
Orthographic projection is related to perspective projection, but the point of perspective is set to an infinite distance.
Maximum FOV: 180°
equatorial mount mode with Hammer-Aitoff projection option.
Landscapes are the scenes used for ground in Stellarium. You can select a landscape from the list on the left side of the window.
From the information displayed on the right side, you will find that each landscape is associated with a planet and a specific location (latitude and longitude). The selection of the landscape will not alter your set location unless you check the "Use associated planet and position" box.
Check the box to show the landscape (ground). If unchecked, objects below horizon will be visible. You can also toggle ground on and off by using the ground button from the lower horizontal bar or by the key [G].
If checked a band of fog will be displayed along the horizon. You can use the key [F] to toggle fog on and off.
If checked the landscape planet and position will be used as the location of the observer.
The information with the selected landscape has the details of its planet and location.
If checked, this landscape will be the landscape Stellarium uses at startup.
Note: This procedure is from Stellarium wiki, landscapes
At the bottom of the Landscape window, there is a button which enables you to add more landscapes.
By pressing the add/remove landscapes button, the following dialog appears:
This allows you to install.zip files containing landscapes. It also lists the user-installed landscapes and allows you to remove them.
You can download .zip files containing landscapes from Stellarium wiki page User Contributed Landscapes (by continent).
Note that while this makes installing landscapes easier, it may also cause you to overlook what else is included in the ZIP archive. Landscape packages created without this feature in mind may contain other files, such as alternative textures in different sizes.
Different people viewed the sky and the patterns of the stars differently. Stellarium provides 14 sky cultures. Each one has a distinctive set of constellations and star names. Western sky culture has the 88 constellations recognized by the International Astronomical Union.
When you select a sky culture, information about it is displayed and you can set it to be your default sky culture that Stellarium uses at startup by checking the box "Use this sky culture as default".