Help

On this page you find a summary of the Web Planetarium functions.

Index

Header bar

Open/Close Main Menu
Change Date/Time
Change Observer's Location

Right Upper Screen

Zoom In
Zoom Out
Lock/Unlock sky movement

Left Lower Screen

Move Time forward/back
You can change the Date/Time of the skymap by adding/subtracting discrete values: Hour, Day, Week, Month, Year. The Now button returns to the current time.
Change Update Timing
You can change the timing speed the skymap is updated every real second or just stop the updating time. Only 2 values are available: 1 second and 1 day, forth and back.
If the map is unlocked, the sky will move accordingly with earth rotation; when it's locked the center marker will remain at the same position.
Open/Close Info Panel
The Info Panel gives you additional information in real time about Julian Date, Greenwich Sidereal Time, Local Sidereal Time at the current moment shown in the Planetarium.
It also shows the Right Ascension and Declination as well as the Hours Minutes Seconds and Degrees, Minutes and Seconds of the Center Marker.
Here you can read the Sunrise and Sunset time, the Moonrise and Moonset time and the Moon Phase at the current time in the Planetarium.
The last line shows the current Field of View (FOV) and both the Magnitudes, the one shown at the current FOV and the one set by default/user choice.
Help
Click to get to this page ;-)
Go to Guestbook
Please consider to sign the Guestbook! Yes, we know it's an old-fashioned web feature: here you can leave your comment and signature, like you would do when visiting a real structure!

Right Lower Screen

Database Search
Enables a dialog box in which you can type what you're looking for.
It contains all the stars in Hipparcos database (41395) that you may search by HIP number, proper name, constellation of belonging; Sun, Moon and the planets of our solar System; all the Messier catalog objects (111) you may search by "M" followed byt he identification number; 1460 objects belonging to NGC; 32 major meteor showers; all the 88 constellations; various comets and asteroids; some asterisms and man-made satellites.
An autocomplete function will help you to select what you need: when selected (by mouse or by enter key) the Planetary will pan to the object and show the relative detail box.
This function is only available in Gnomonic projection.
Open/Close Planets Hotkeys
Toggle Planets markers
Toggle Planets labels
Start/Stop Planets Journey
Open/Close Stars Hotkeys
Change default magnitude
Change stars scale
Toggle Alpha star labels
Toggle Non-Alpha star labels
Toggle stars blinking
Open/Close Constellations Hotkeys
Toggle Constellation Lines
Toggle Constellation Boundaries
Toggle Constellation Labels
Toggle Milky Way Boundaries
Open/Close Skymap Hotkeys
Toggle Center Marker
Toggle Ground
Toggle Ecliptic Line
GoTo Coordinates (dialog box)

Keyboard and Mouse controls

        
Keyboard arrows to move map
(SHIFT + Key to move faster)

Mouse wheel (or Numpad +/-) to zoom-in/out the skymap

Main Menu

On the top left of the screen you find the "hamburger icon" click on it to make the menu appear. Here are the menu voices description and features:
  • Stars
    • Stars On/Off
      Show/hide the stars in the skymap
    • Alpha Stars Labels
      Toggle the labels for the α stars
    • Non-Alpha Stars Labels
      Toggle labels for the non α stars
    • Stars Blinking
      Toggle star blinking, emulating the air turbulence
    • Stars Glowing
      Toggle star glowing, puts a halo around the star dots
    • Scaling
      Here you can change how big are the dots (stars) on the screen. The dots proportion related to magnitude is respected.
  • Constellations
    • Select constellation
      Here you can select one of the 88 constellations the sky is divided into.
      Upon selection the skymap will rotate to center the view and the Constellation Detail will show.
    • Constellation Lines
      Show/hide the constellation lines to help you recognize them in the skymap.
    • Constellation Labels
      Show/hide the constellation labels. When you put the Center Marker on the first letter of the label, the Constellation Detail will show.
    • Constellation Boundaries
      Toggle the constellation boundaries
  • Planets
    • Planets
      Toggle the Planet markers on the skymap
    • Planets Labels
      Show/hide the Planet labels
    • Planets Journey
      Start/stop the Planets Journey
    • Orbits
      Opens a sub-menu where you can choose which Planet Orbit has to be shown on the skymap.
  • Sky Objects
    • Meteor Showers
      Toggle the major meteor showers. You can choose whether to view all shower markers or one by one.
      Active showers are marked in green, while those not visible on the current date are grayed out.
    • Messier
      Show/hide the entire Messier object catalog. You can choose whether to display all markers at once or individually.
    • NGC
      Show/hide the entire NGC object catalog. You can choose whether to display all markers at once or individually.
    • Comets
      This menu contains some of the most notable comets that have recently passed close to Earth. You can view their current positions one by one.
    • Asteroids
      Here you can choose to show some of the most easily visible asteroids on the sky map.
    • Asterisms
      This menu contains some of the most important asterisms. Asterisms are lines and/or geometric shapes that allow you to locate other points, stars, constellations and/or other celestial objects.
    • Man made
      Here's a list of some of the brightest artificial satellites. Clicking on each name displays its current position (as of the Planetarium date) and displays the satellite's path over the next few minutes.
  • Magnitude
    • Select the minimum reference magnitude. The Planetarium will return to this level when the FOV is greater than 60 degrees.
  • Map
    • Galaxy Boundaries
      Toggle the borders of the Milky Way.
    • Cardinal Points
      Toggle the markers for North, East, South and West on the skymap.
    • Atmosphere
      Show/hide the light gradient due to the atmosphere refraction.
    • Ground
      Toggle the ground, hiding the sky below the horizon.
    • Marker Ra/Dec
      Show/hide Ra/Dec values of the Center Marker just to the right of it.
    • Marker Hms/Deg
      Toggle Hms/Deg values of the Center Marker just to the left of it.
    • Negative Mode
      Change the appearance of the Planetarium by inverting the background and foreground colors and making them black and white, making them useful for printing.
    • Night Mode
      Change the Planetarium display, making almost all colors reddish, to avoid pupil dilation.
  • Lines
    • Ecliptic
      Toggle the Ecliptic, the orbital plane of Earth around the Sun, i.e. the apparent path of the Sun throughout the course of a year.
    • Meridian
      Toggle the Meridian, the great circle passing through the celestial poles, as well as the zenith and nadir of the observer's location.
    • Azimuth Grid
      Toggle the grid having lines passing through zenith and nadir and the 4 cardinal points.
    • Equatorial Grid
      Show/hide the grid having lines projected onto the celestial sphere mirroring Earth's latitude and longitude lines.
    • Galactic Grid
      Toggle the grid having lines relative to the plane of our galaxy, the Milky Way.
  • Projection
    • Gnomonic
      This is the default appearance and the best to use in the Planetarium. It's a map projection that displays all great circles as stright lines.
      It has full functionalities, except for the Atmosphere feature.
    • Stereographic
      It's a perspective projection of the sphere through the pole (the center of projection) onto a plane, perpendicular to the diameter throught the point.
      For calculation and/or display issues it may lack some of the Planetarium features.
    • Lambert
      It's a projection method developed by Johann Heinrich Lambert in the 18th century.
      For calculation and/or display issues it may lack some of the Planetarium features.
    • Equirectangular
      In this projection every pixel represents the same number of degrees of latitude and longitude for planets, and degrees for Right Ascension (RA) and Declination (Dec).
      For calculation and/or display issues it may lack some of the Planetarium features.
    • Mollweide
      This projection is an equal-area pseudocylindrical map projection displaying the world in a form of an ellipse with axes in a 2:1 ratio.
      For calculation and/or display issues it may lack some of the Planetarium features.
    • Planechart
      In this projection the whole sky is represented in a plane.
      For calculation and/or display issues it may lack some of the Planetarium features.

Detail Boxes

Star
When you put the Center Marker over a Star its detail box appears on the center bottom of the screen. If the pointed star is an α (alpha) one, the details are shown in green:
The details are shown in yellow when a star has a Bayer denomination and is a non-alpha:
All the other cases the star details are shown in white.
Please note that colors may be different when Negative or Night Mode are selected.
to open the side panel with picture
When the star gets out the Center Marker the detail box disappear.
Constellation
The Constellation detail appears as follows:
  • after completing a Database Search for a constellation
  • after selecting a constellation from the "Select constellation" option in the main menu
  • by moving the Center Marker over the first (underlined) letter of the constellation label on the map
The box contains a brief description of the selected constellation and have some buttons:
display the image from Bayer's Uranometria (if available)
display all the star names of the constellation
center the constellation on the skymap
minimize the detail box
exit from Constellation detail
Planets
When a Planet is inside the Center Marker the relative detail box is shown.
open satellites details (if available)
show/hide the planet orbit
open Side Panel with planet surface image and data
To exit the detail box just move out the planet from the Center Marker.
Planets Journey
The Planets Journey allows you to navigate through the planets of the Solar System. When enabled it starts from Mercury, panning the skymap to its position and showing the following detail box in the bottom part of the screen:
navigate to the next planet
navigate to the previous planet
show/hide the planet orbit
minimize the detail box
exit Planets Journey
When you reach Neptune going forward, or Mercury going backward, the navigation will cycle to the first or the last planet respectively.
Sun and Moon
Use the Database Search or just move the skymap to find Sun or Moon position in the sky and put them into the Center Marker.
The Sun detail box shows its position on the sky and sunrise/sunset times at the date of the Planetarium.
Similarly the Moon detail box shows our satellite's position on the sky, moonrise/moonset times at the date of the Planetarium. The moon phase and the percentage of illumination are also shown.
open Moon Phase extended details
open surface detail and other info
Meteor Showers
Use the Meteor Showers option under Sky Objects in the Main Menu to search for the shower you're interested in. Meteor details appear when the Center Marker is positioned in the center of the skymap.
The detail box shows the shower's name and the period of activity. If the Shower is visible at the current time of the Planetarium the text is displayed in green otherwise it's grayed out.
If you choose in the Menu to show all the Showers, you can move the skymap from one to another to check their data.
Messier and NGC objects
When the Center Marker is over one object belonging to Messier or NGC Catalog, the relative detail box appears:
open the side panel with picture
Comets and Asteroids
Select a Comet or an Asteroid from the Main Menu to see it on the skymap. After the panning to the point where the object is positioned on the sky, the relative detail box appears on the center bottom of the screen.
Each box reports the main data related to the observed object,
No extended detail are provided at the moment.
Asterisms
Select an Asterism from the Main Menu to see it on the skymap. After the panning to the point where the shape is positioned on the sky, the relative detail box appears on the center bottom of the screen.
A brief description explaining the Asterism is provided.
re-center the Asterism
minimize the detail box
exit Asterism detail
Man Made
Select an artificial object from the main menu to display it on the sky map. After selecting, the positioning data is retrieved and the map moves to the object's current position in the sky, along with its orbit for the next 5 minutes.
You may read a brief description of the currently selected object.
re-center the Man Made Object
minimize the detail box
exit Man Made detail

Moon Phases Panel


Main Box

As you enter the page you can see a picture of Moon at the current phase: under the image there are all the data regarding the Moon at the reported date and time.

You can move forth and back in time by clicking the buttons placed above the image: intervals are 1 hour, 1 day, 1 month. To get back to current date and time press the "Now" button.

Please note that the time is always running, whenever is the date set.

Next Phases

The bottom box contains the 4 next phases of the Moon occurring from the date shown in the main box. For each of the next phases the date and time are displayed.

Jupiter's Moons Panel




As the page loads up you will see what's on the hereabove image: for practical use the page is divided into boxes.

Main View

The upper box is the Main View and it shows the planet Jupiter on the center and its 4 galilean satellites positioned at current date and time.

Please take note that the view is like you're observing the planet with a binocular, therefore if you're using a telescope you have to consider to rotate the image by 180°.

Also take note that Jupiter rotation is not shown, therefore the Giant Red Spot on the planet surface is there just for display purpose: if you're observing with a powerful telescope, the spot might be in another position or hidden.

Human Play

Just under the Main View to the left you find the Human Play box: by pressing the buttons can simulate to move forward or backward in time by fixed amount of time. Intervals are: 10 minutes, 1 hour, 1 day, 1 month, 1 year. The "Now" button at the center takes you back at current time.

Time Selector

Here you can change the Date and Time according to your needs: click on the input boxes to get each own popup in which you can set the data as you wish.

Autoplay

Let the time run! You can warp the time up and down, just select the amount of seconds, minutes or even days you wish to go forth or back.
To stop the time running just press the Stop button. To take the view back to the current time press "Now" button in Human Play.

Satellites

In the bottom row you can see 4 boxes corresponding to the Galilean Moons.

For each satellite an image is shown and the diameter (in Km) and the orbital period are reported. When the satellite is in transit (passing over Jupiter) the box border is shown in green color, when in occultation (passing behind the planet) the border becomes blue and the satellite image is hidden.

X and Y values are the pixel coordinates related to the Main View center: they are shown for testing purpose.

Night Vision

In order to preserve a better night vision when switching from your observation instrument to the device you're consulting the page (without affecting your pupillary enlargement) you can change the text color display by pressing the button "Set Night vision" located in the upper right corner.

All texts will be shown in red and satellites images will be hidden: to get back press the same button, now labeled "Set Day vision".

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