N i g h t    V i s i o n


Version 1.3.1
Copyright (C) B. Simpson 2007
Astronomy Program for Java

 

Night Vision is a "planetarium" program for Java, and will display the heavens from any location on earth. Viewing options allow the user to control which sky objects to display, which font to use, and manipulation of various star parameters. Time may be set to run at multiple speeds, including backwards. Color star charts may be printed.

Because this program is written in Java, it should be able to run on any computer with a recent version of Java installed. (See Requirements.)


Night Vision on the Internet

Night Vision has a home page on the Internet at:

    http://home.att.net/~bsimpson/nvj.html

Currently you can contact the author at:

    bsimpson@att.net

This address is heavily SPAM'd, and so it may change in the future. Check the web page for the latest address. It is a good idea to prefix your Email subject line with [NV], as in

    Subject: [NV] Like your program!
so that it is easily distinguishable from SPAM and is less likely to get inadvertently deleted.


Disclaimer

Night Vision is provided "as is" without warranty of any kind. No warranty is made, expressed, or implied, that this documentation or accompanying software is free of error, or is consistent with any particular standard of performance, quality, or merchantability, or that it will meet your requirements for any particular application. You assume all risks associated with the use of this software, including, but not limited to, the risks of program errors, damage to or loss of data, programs, or equipment, and unavailability or interruption of operations. The author and distributors disclaim all liability for direct, incidental, or consequential damages. Your use of this software constitutes total agreement and acceptance of this disclaimer.


Requirements

- Software -

Night Vision should run on any computer that contains Java software known as the Java Virtual Machine (JVM), which is usually part of a Java Runtime Environment (JRE). It is the JVM that allows a Java program to run on any machine and operating system. Various versions are available for most operating systems.

Night Vision requires Java version 1.3 or later. To see what version is on your machine, issue the following command:

    java -version

Note: Windows users may have access to a downloadable self-installing package that includes JVM 1.3. This version should run on any Windows machine, with or without Java pre-installed.

- Hardware -

Parts of Night Vision were developed on a 90MHz Pentium computer. It is possible to run Night Vision on such a machine, but it is not recommended, as it will run agonizingly slow. A minimum recommendation is at least a 200MHz Pentium or comparable processor with 64MB of RAM. Most systems created this millennium should have no problem running Night Vision.


Starting Night Vision

If Night Vision is downloaded as a self-installing package (i.e. clicking on an install link from a web page), an icon should be installed on your computer. Clicking on this icon should start the program.

Otherwise if Night Vision is downloaded as a zip file, extract the files into a directory on your hard drive and issue the following command from a command prompt in that directory:

    java -jar nvj.jar
or
    java -cp nvj.jar nvj.Nvj

Java is case sensitive, so type the commands exactly as shown.

On some systems (e.g. Windows) users can double click the left mouse button on the nvj.jar file icon to start the program.


Your first view

Night Vision opens with a view of the heavens looking straight up from the user's preferred location. (Or, until a preferred location has been selected, a default location of Niwot, Colorado, the author's favorite small town.)

Two scrollbars control the direction of view:

Altitude and azimuth are indicated in the information window at the top.

A third scrollbar, at the left side of the window, controls the zoom (or magnification) of the view. To zoom in, move the scroll up. To zoom out, move the scroll down. You can also zoom in and out by pressing 'z' and 'Shift-z'. By pressing 'Shift-z' and/or enlarging the window an entire 180 degree view can be seen. (I.e. 90 degrees in all directions from center of window.)

A fourth scrollbar can be added to the top of the window via the "Window preferences" window. This scroll rotates the view around its center.

Night Vision is designed for ease of use with the mouse. The mouse can be used to center an object, identify an object, or to zoom towards an object. For example, to move an object to the center of the window, left click on that object. To zoom towards an object, draw a rectangle around that object by pressing the left mouse button and then dragging the mouse. When the button is released the center of the rectangle is moved to the center of the window at a zoom level based on the area of the rectangle. (Press 'p' to return to the previous view.)

Objects can be identified by clicking with the right mouse button.


Setup

Night Vision can be set up for any location on earth. Begin by going to the "Set location" window (via the "Set" pull down menu). Select the location closest to your location and press "OK Location". Or enter your longitude, latitude, and time zone values and press "OK Coordinates". If your new location is in a different time zone, then your local time (as displayed in the information window above the star window) will have changed, and you must reset the time. To do so, go to the "Set local date/time" window (via the "Time" pull down menu), and then press "Set to computer date/time". You are now re-sync'd to your computer time.

Be sure to save this location information if you would like Night Vision to always start at this position. Go to the "File" pull down menu and select "Save location".

You may also save your viewing preferences (objects, fonts, colors, star parameters, ...) by selecting "Save preferences" from the "File" pull down menu.

Note: The location database used in the "Set location" window may be edited to suit the user's preferences. See "User editable files" in the online help.


Translating Night Vision

Night Vision has been designed to be readily translable into other languages. See the online help for information.


Shareware

Night Vision is released as "free" shareware, i.e. free for private, non-commercial use. Although there is currently no registration fee, if you use the program regularly, the author would appreciate hearing from you! Also contact the author for commercial use.

Night Vision may be freely copied as long as it remains in its original unmodified form. An exception is made for translations to other languages. In this case the translation should accurately reflect the original English version.


List of files

When the Night Vision zip file is downloaded from the Internet, it will likely be named as follows:

    nvjvv.zip

where vv is the version number (10 represents 1.0). The suggested convention for other language versions is to have a 2 character language designation after the version number. For example a German version 1.0 will be represented as nvj10de.zip.

Unzipping the package file produces the following two files:
nvj.jar The Java file containing the Night Vision program
nvj.htm Documentation (this file) to be read by a web browser
 
The program creates the following file to store user preferences in:
nvj.ini Initialization file
 
The user may request the program create the following 3 files to be modified by him/her:
nvj.loc Location file
nvj.ds The deep sky object file
nvj.stn The star name file

If Night Vision is downloaded as a self-installing package, in addition to the above files several other files (and a subdirectory) will be included to support the install/uninstall process.


Misc. notes

The star database is derived from the "SKYMAP SKY2000 Master Catalog, Version 2". It contains 17,000 stars (through 7th magnitude).

Various sources were used for the algorithms employed by Night Vision. Among them are Practical Astronomy with your Calculator (3rd edition) by Peter Duffett-Smith, and Astronomical Algorithms (2nd edition) by Jean Meeus.


Future updates

Night Vision may be updated in the future. Future updates may include:


History

1.3 Added labels for grids. Enhanced accuracy and added angular size and distance for solar system objects. Added planet magnitude. 1.3.1: Fixed bug where "Select object" window did not show when running on Java 1.3. Also adjusted how time restarts when "thawed".
1.2 Added precession and nutation. Expanded range of time to 1000AD - 3000AD. Added phases of the moon. Corrected a problem displaying the preview area in the "Set colors" window that occurs with some versions of Java. Added a web-based self-installing version for Windows users.
1.1 Corrected "Star database file nvj.db is corrupted" problem on Mac OS X JVM 1.4.1_01. Mercury & Venus can now appear in front of sun.
1.0 Initial Release