Launching the Milky Way Atlas
Launching the Milky Way Atlas
Let's begin a quick orientation to the Digital Universe by launching the Milky Way Atlas. Follow these instructions for your operating system:
Windows: Double-click on the milkyway.bat file.
Mac OS X: Double-click on the milkyway.command file.
Linux or IRIX: Run the milkyway.sh shell script.
Each file launches Partiview and reads a file called mw.cf, which loads and sets the display for the Milky Way Atlas.
Mouse Controls
Partiview is designed to function optimally with a three-button mouse. We recommend using at least a two-button mouse for navigation. Using a laptop trackpad to fly is difficult. If you're using a one-button mouse on a Macintosh, the Option key along with the mouse button will emulate the right mouse button.
In this guide, we will use these conventions:
- left mouse button, left-click
- Refers to the left-most mouse button, or the singular mouse button on the Mac.
- right mouse button, right-click
- Refers to the right-most mouse button. If you are using a one-button Mac mouse, press the Option key along with the mouse button.
- middle mouse button, middle-click
- Refers to the middle mouse button on a three-button mouse.
Beginning to Fly
The Milky Way Atlas opens with a view toward the constellation Orion and the bright stars Sirius and Procyon. If you move the mouse in the Graphics Window (where the stars are) while pressing the left mouse button, you will pan around the sky (as if moving your head without moving your feet).
Turn the stars off by pressing the g1=stars group button in the upper left and turn on the open clusters (the oc button) and the globular clusters (the gc button). Also turn on the constellation connectivity lines (constel button) so that you know where you are in the sky.
Increasing the Window Size
If you are able to fly around with ease, try enlarging the window. You may want to do this slowly in case the graphics demand is pushed too high for your machine (at which point your computer will grind to a halt). If your machine freezes, either shrink the window or close it and wait for your computer to catch up.
Activating Data Groups
In order to alter the properties of a data group (brightness, color, label size), you must make the data group active. By default, the stars are the active group when the Milky Way Atlas is launched. You can verify that by inspecting the active-group indicator below the Groups Menu. It is located next to the More Menu in the upper left and should say [g1] to indicate that group 1 (stars) is the active group.
Let's make the open clusters the active group by either right-clicking (Option-clicking for Mac OS X) on the oc group button or selecting g6=oc from the Groups Menu. Now the active-group indicator below the Groups Menu should read [g6].
Brightening the Open Clusters
Now that the open clusters are activated, you can change their appearance. Start by making them brighter. Use the slider in the upper-right corner of the window.
This is a multipurpose slider that, by default, comes up as the Slum Slider. The slum command sets the scaling factor on the luminosity in Partiview. If you put your mouse on the value adjuster and move it back and forth, you will notice the open clusters becoming bright and dim.
Below the Slider Menu is the word slum, indicating that the slider is set to change the slum value. Set the group's brightness to the maximum value, then select alpha in the Slider Menu. Alpha acts as a fader and sets the transparency of the green polygons that represent the open clusters.
Moving the slider up and down, you can see that this is another way to effectively set the brightness of the polygons.
Leaving Earth
When the Milky Way Atlas is launched, you are sitting on the Sun and viewing the night sky as seen from Earth. With the left mouse button pressed, you can pan around the sky to your heart's content. How do you move away from the Sun, though, and begin flying around the stars? Turn on the stars and turn off the open clusters and globular clusters (click on their group buttons).
Beside the Groups Menu is the Flight Mode Menu. Partiview launches with Orbit Flight Mode as the default active flight mode, as indicated by the word [o]rbit below the menu.
To leave the Sun, choose the Fly Flight Mode from the Flight Modes Menu. Now, with the right button pressed (Option-mouse for Mac), move the mouse toward the left. You're moving in reverse, flying away from the Sun.
Once you move away from the Sun, switch back to Orbit Mode by selecting it from the Flight Mode Menu or by typing a lowercase ‘o’ in the Graphics Window (where the stars are displayed). This is a keyboard shortcut (see the Partiview User's Guide for a list of keyboard shortcuts). Now use the left mouse button to orbit the Sun and the right button to move forward or backward.
With this brief introduction to Partiview and the Digital Universe, let's look at Partiview's flight modes and mouse functionality in the next section.
© 2002-2005 American Museum of Natural History
Last Modified: 2007-12-19 by Brian Abbott