User`s guide

192 Starry Night User’s Guide
The correct time is shown in the toolbar
when I start Starry Night, but the sun
rises and sets at the wrong time. How do
I fix this?
Most likely you have entered the wrong
time zone for your home location. Choose
Set Home Location from the File menu
(Windows) or the Starry Night menu
(Macintosh) to see what the time zone is
set at, and change the time zone in this
window if necessary. If you do not know
your time zone, see the next question.
How do I find my time zone?
Time zones are in relation to London,
England. People on Eastern Time are 5
hours behind London time, so they should
put "-5h" for their time zone. Those on
Central Time would enter "-6h" and so on.
Visit the World Time Zone Map at http://
aa.usno.navy.mil/AA/faq/docs/
world_tzones.html if you do not know the
time zone of your home location.
Do the sunrise/sunset times account for
the refraction of light due to the earth's
atmosphere?
Yes. The bending of light due to the
Earth’s atmosphere is accounted for by
simply lowering the horizon about 1/2
degree. This gives the correct rise and set
times for the sun and moon but doesn’t
affect the relative positions of the stars.
How does Daylight Saving Time work in
Starry Night?
When you start up Starry Night, the
program checks your computer's date/time
settings to find out if Daylight Saving
Time is in effect for the current date, and if
so, automatically adjusts the sky to
account for this. If Daylight Saving Time
is "on" in Starry Night, the little icon of the
sun immediately to the left of the time in
the toolbar will be coloured yellow. Click
on this icon to turn off Daylight Saving
Time (if Daylight Savings Time is already
on, clicking this icon will turn it off). Note
that Starry Night only checks to see if
Daylight Saving Time is in effect when
you open the program. This means that
you may have to turn on or off Daylight
Saving Time if you change the date from
within the program. For example, let's say
you open the program in June. Starry
Night checks with the operating system
and determines that Daylight Saving Time
is in effect, so the icon of the sun in the
toolbar is lit up. However, you are
interested in viewing a solar eclipse in
December, so you change the date in
Starry Night to sometime in December.
Starry Night will not automatically turn
Daylight Saving Time off. You need to
click on the icon of the sun to manually
turn Daylight Saving Time off.
Can I get Starry Night to show the time
using the 24-hour clock?
Yes. On Windows, Starry Night looks to
the Windows registry to determine the
time format. If it can't find a registry entry
for regional date settings then it defaults to
the 12 hour clock. Unfortunately UK
Windows does not automatically place the
date format in the registry where Starry
Night expects to see it. To work around
this, you should open the "Regional
Settings" control panel, switch the time
format to something other than the current
setting, click OK, then reopen the