Digital Universe Guide - Hayden Planetarium

12 2. GETTING STARTED
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
(press ESC) 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 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.