Other astronomy activities
An electronic Lesson and Exercise "The Life of Stars and their Spectra"



"SpectrJ" is the exercise provided by Greece. It is developed by:
Dr. Margarita Metaxa,
Dr. Ioannis Bellas-Velidis,
Dr. Anastasios Dapergolas,
Dr. Aglaia Bobetsi.
It is an electronic pedagogical tool for secondary schools that aims to provide a ready-to-use resource, inspired by real observations and research activities applying modern processing techniques. This tool presents to you an e-Lesson and a corresponding e-Exercise focused on the stellar spectra and their importance in astrophysics. Travelling through the pages of the lesson you will get basic information on light and its spectra, on the stellar spectra and their classification into spectral types, and how they provide us with knowledge about the stars and their life. This lesson will be the theoretical base to understand the exercise. On the other hand, by doing the exercise you will follow, in a simplified manner, the steps taken in a real research project. You will find the age of stellar systems in the neighboring galaxy SMC by classifying and analysing the spectra of their stars.
Languages supported:
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Introduction to![]() |
INTRODUCTION |
What is SpectrJ ? | ||||
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Why SpectrJ ? | ||||
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Learning objectives | ||||
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About

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1. INSTALLATION
1.1 MS-Windows standard installation: SpectrJ_setup.exe
This setup includes ImageJ 1.36, Java JRE 1.5.0_06. There is an executable setup file SpectrJ_setup.exe (about 40MB). Running it, the SpectrJ is installed automatically and a shortcut SpectrJ will be created on your desktop to run it. This setup includes the ImageJ ver. 1.36b, a public domain Java image processing program by Wayne Rasband at the National Institute of Mental Health (see http://rsb.info.nih.gov/ij), bundled with Java (JRE 1.5.0_06). Uninstalling SpectrJ will uninstall also the ImageJ.
1.2 MS-Windows plugin installation: SpectrJplugin_setup.exe
Only SpectrJ plugin and windows launcher SpectrJ.exe are included. There is an executable setup file SpectrJplugin_setup.exe (~20MB). If you already have the ImageJ (version 1.34 or above) installed, this will install only the plugin subdirectory SpectrJ and SpectrJ.exe launcher. You can create a shortcut to the launcher on your desktop. Uninstalling SpectrJ will not uninstall your ImageJ.
1.3 LINUX/UNIX plugin installation: SpectrJ.tar.gz
This setup contains only the SpectrJ plugin. You should have ImageJ (version 1.34 or above) for your system already successfully installed (see http://rsb.info.nih.gov/ij). Unzip and untar the SpectrJ.tar.gz under the ImageJ's plugin directory. This will create a SpectrJ subdirectory with the plugin. You can then run SpectrJ as plugin from the ImageJ Plugins menu.
2. RUNNING
2.1 MS-Windows SpectrJ executable run
You can start the SpectrJ double-clicking on its icon created on your desktop after successful installation. Temporary appears the ImageJ toolbar that is then replaced by the SpectrJ main window. Here you have the controls to access the different functions of the SpectrJ (Introduction, e-Lesson, Help, e-Exercise, About, Language, and QUIT). Quitting the SpectrJ, closes its Main Menu, temporary reappears the ImageJ and exits automatically (you have no access to ImageJ itself). This executable-type run is available independently of the installation method on MS-Windows.
2.2 MS-Windows ImageJ/SpectrJ plugin run
You can also run the SpectrJ from the ImageJ. Start the ImageJ program double-clicking on its icon. Click on the Plugins on the ImageJ menu, this opens a list of items, point to the SpectrJ and then click on the SpectrJ tab that appears on the right of the list. The ImageJ toolbar disapears and as above appears the SpectrJ Main Menu. Here, quiting the SpectrJ only closes its menu and reapears the ImageJ available for use. The plugin-type run is available independently of the installation method on MS-Windows.
2.3 Linux/UNIX ImageJ/SpectrJ plugin run
In this case, you proceed exactly as in the MS-Windows plugin run. An executable-type run is not available in this installation method.
2.4 SpectrJ rerunning
In either case, if you have already executed (partially or totally) particular task of the eExercise and then exited, rerunning this task will automatically show the already executed steps. This is true if you are reentering with the same working code as before (see Section 4 below).
3. PARAMETERS (optional, influencing the eExercise only)
There are four optional parameters for modifying the eExercise execution. They are provided as a way to speed up the interactive execution of the exercise if this is necessary. The parameters are in the SpectrJ.properties file in the plugins\SpectrJ subdirectory (an editable text file). There are comment-lines (line starts with #) and parameter-lines (name = value). Do not change spjTitle and spjVersion parameters. The other four parameters are for running the e-Exercise and affect only the way the COMPLETE button is available for an automated completion of the particular task (Detection, Extraction and Classification, see the ExerciseHelp). This COMPLETE button switches on an automated execution of the particular task up to the task's end without user interaction, only displaying the tasks steps.
minTasks = 4
After completing (100%) of this number of tasks of a given type, the COMPLETE is always available for this type tasks (say, after full finishing the Detection for the AF, AS, BF, BS, the COMPLETE is always available for the Detection task of the remaining CF and CS field/frame), no matter the parameters below
minDetect = 5
After detecting of this number of objects the COMPLETE button is enabled for the particular DETECT task
minExtract = 3
After extracting of this number of spectra the COMPLETE button is enabled for the particular EXTRACT task
minClassify = 6
After classification of this number of spectra the COMPLETE button is enabled for the particular CLASSIFY task
4. USER WORKING SUBDIRECTORY
Running the eExercise creates a working subdirectory under the user's home directory (e.g. under C:\Documents and Settings\username on MS Windows XP Pro). The name of the working subdirectory is fixed in the beginning of the eExercise run by specifying a "Work Name" on the start dialog request. This subdirectory is never deleted by the SpectrJ. It contains the current state of the execution of the eExercise by the user and is used to restore the already executed task(s) in a case of temporary exiting and rerunning SpectrJ again. But, you can simply delete the working directory after the user has finished the exercise. So well, different users if they are working under the same user name on the particular computer should use different work names (see the eExercise Help).
5. EXERCISE RESULT
The final result of this exercise, after all the tasks completing is always the same. This is due to the fact, that the user is not allowed to misidentify or to skip spectra during the detection and to classify exactly their spectral type, so the final statistics, wherefrom the result is obtained, is always the same.
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Languages (internationalization of SpectrJ)
LANGUAGES By default the base installation is provided for English and Greek languages only. There are three types of objects where the "translation" has to be applied if you wish to implement the SpectrJ in your preferred language. These objects are: A. java programs, B. html pages, C. images with text. Following the instructions bellow, will assure automatic recognition and use of the new language by the SpectrJ. If you followed the standard installation, the base directory mentioned below is C:\Program Files\ImageJ\plugins\SpectrJ |
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A. | eExercise (java program) | |
The internationalization here is based on the JAVA-language standards. There is a subdirectory "Locales", under the base directory, where the different language files should exist. By default there should be the following three files: spjBundle.properties - the base file that should not be changed spjBundle_el.properties - the greek language file spjBundle_en.properties - the english language file (base file copy) These are text files with comment lines (starting with #) and parameters lines. Each parameter line starts with the parameter name, follows three characters (space, =, and space), and then is the parameter value to the end of the line. The value is in UNICODE representation, see below, except for the base and the english language files. The steps you should follow are: |
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a. | Make a copy of the spjBundle.properties file and name it spjBundle_??.txt where "??" should be the two-letter ISO-code for your language. For example el - greek en - english es - spanish fr - french it - italish pl - polish pt - portuguese sv - swedish |
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b. | Open the txt-file with simple text editor (say Notepad) and replace the text in the value part of the parameters with your translation. Do not change the names. It is not necessary to translate the comments. Please, remember that each parameter (name = value) should be on one line (there is a "\n" command in the text for breaking line if this is necessary), no matter how long it is. | |
c. | Optionally, and only if your language is none of the above listed, you should update in your text-file the parameter allLanguages. Currently it is allLanguages = enelesfritplptsv and it should be allLanguages = enelesfritplptsv?? where ?? is your language ISO-code. Then, you should add a new parameter ??_Language = ??????? after the last Language parameter with ??????? being the name of your language (this will appear on particular button on the SpectrJ menu). |
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d. | Convert the spjBundle_??.txt file to UNICODE naming it spjBundle_??.properties. To convert to UNICODE you can use the JAVA's native2ascii program native2ascii inputfile outputfile This program is included in the Java Development Kit that can be downloaded for free (as of June 2006, Java 2 Platform Standard Edition JDK 5.0 Update 6) from http://java.sun.com/j2se/1.5.0/download.jsp Under MS Windows the JDK is installed by default under the C:\Program Files, so in this case open the Command Prompt window, change to the Locales subdirectory, and run "c:\Program Files\Java\jdk1.5.0_06\bin\native2ascii" spjBundle_??.txt spjBundle_??.properties (all in one line). It is not recommended to remove the txt-file (it is good to save it somewhere out of the SpectrJ for the case you would like to correct your translation). |
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The english language spjBundle_en.properties file can also be updated, say to correct our english. This can be done directly on the properties file without transforming it to UNICODE. But, please do not change the base spjBundle.properties file. | ||
B. | ExerciseHelp (html and images with overlying text) | |
In order to have also the ExerciseHelp available in your native language you should prepare your language version of the Help. Else, the english version will be used. The Help is a set of HTML-files and the "translation" task here is quite different. | ||
a. | Go to the directory ExerciseHelp and copy all the EN subdirectory (english version) to a new one named ?? where ?? is the two-letter ISO-code for your language (see above) in capital-letter case. | |
b. | Go to the new subdirectory and edit one by one the HTML-files with your preferred html-editor (you can use also the Notepad under MS Windows). Translate, whenever it is necessary the english text (not the html commands) to your language. Please, be careful not to change the overall shape of the html-page as it has predefined size that can not be changed nor the content can be scrolled. So, it is preferable to use WYSIWYG-type html-editor. | |
c. | Under the ??\images subdirectory there are some images used by the html-pages that have english-version text. Most of them are simply screen copies from running the SpectrJ. You can replace them with the corresponding taken while running SpectrJ in your language after the step A. above (do not change the image file names). Under MS Windows, use Alt-PrintScreen key combination on your keyboard to copy the active window, then paste it (usually with Ctrl-V keys) to your image-editor, get the necessary part of the image resize it to the "english"-version image's size and replace the original image file with the new. This should be done for the images: Intro1.jpg Intro2.jpg Tasks.jpg Detect.jpg Extract.jpg Classify.jpg Analyze.jpg Result.jpg The text on two more images should be changed directly using your image editor. These are SpectrJ_title.jpg spectr_extract.jpg Please, be careful with the jpg-compression (high values could make unclear the resized image)! |
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C. | The "translation" of the eLesson is similar. There are html-pages and lot of images with text on them. If there is no your language version of the lesson, the english version will be used. | |
a. | Go to the directory eLesson and copy all the EN subdirectory to a new one named ?? where ?? is the two-letter upper-case ISO-code for your language (see above). | |
b. | Go to the new subdirectory and edit one by one the HTML-files with your preferred html-editor (you can use also the Notepad under MS Windows). Translate, whenever it is necessary the english text (not the html commands) to your language. Please, be careful not to change the overall shape of the html-page as it has predefined size that can not be changed nor the content can be scrolled. So, it is preferable to use WYSIWYG-type html-editor. |
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c. | Finally, there are about sixty images that should be edited directly with your preferred image-editor. Most of them are under the subdirectory eLesson\??\images SpectrJ_title.jpg (the same as in ExerciseHelp) wavelengths.jpg Image1_1d.jpg Image1_2a.jpg spic-sun-ant.jpg SunCenter.jpg Image4_1b.jpg Image4_3.jpg m45_m11_m3.jpg the other are buttons and images for interactive displaying, that are under particular subdirectories: eLesson\??\images\drop-rainbow\ button_all.gif button_next.gif raindrop?.jpg (? is 1,2,3,4) eLesson\??\images\spectra_em_ab\ spectraEmAbs_button?.gif (? is 0,1,2,3) spectraEmAbs?.jpg (? is 0,1,2,3) eLesson\??\images\planck_graphs\ planck_button5.gif planck?.jpg (? is 1,2,3,4,5) eLesson\??\images\elements_spectra\ Element_base_ab.gif Element_base_em.gif Element_ab99.gif Element_em99.gif eLesson\??\images\hipparcos_h-r\ button?.jpg (? is 1,2,3) hip_hr?.jpg (? is 1,2,3) eLesson\??\images\evolution\ ev_base?.jpg (? is 1,2) ev_?4.jpg (? is dwarf,normal,giant,super) eLesson\??\images\cluster_evo\ button_?.jpg(? is 0,all) evolution_?.jpg(? is 0,8,256,3000,8000,all) eLesson\??\images/smc_ages\ smc_age?.jpg (? is 0,1,2,3,4,5,6,7,8) |
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