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Using HERA

The Hera program allows the user to run the ftools remotely from a local computer on a machine at Goddard Space Flight Center on data stored in the user's temporary Hera account (again on a Goddard computer). Data sets are also included with the education version of Hera.

If you need to install Hera on your computer, you may do so now.

Show me how to install Hera

Now that you have installed the Hera module, you can begin to use the Hera tools to examine and analyze X-ray data. The interface is very straightforward. After installing the Hera module, you are ready to start!

A typical Hera analysis session usually consists of two distinct operations, selecting the data in your Hera account and selecting and running a tool to use within Hera to analyze the stored data. The output will be displayed on your computer, and you can print out or save plots and other output locally.

To log in the first time, click on the Teachers Hera icon on your desktop (when you install Hera, the install wizard will put a shortcut on your desktop). A login window will appear, which looks like the graphic below. When you click on the "login" button, the Hera module on your computer will connect to Goddard's computers. When the connection is made, you are ready to begin. A user name will be assigned to your computer so that you can access your account later. Your account will remain active as long as you login at least once every 30 days. When you want to log in again, you will again click on the Teachers Hera icon. The login window that comes up should have your unique Hera login displayed, and you can click on "login" and access your account.

login graphic screenshot

When you are logged in, the main Hera window (click for sample image) will appear, which is divided into 3 main areas:

  1. Upper Left window: list of all available software tools, organized into packages. Below the tools are two buttons: "run" executes the selected tool while "help" provides a detailed description of the tools and its parameters. When you click the "help" button, a window with the detailed help will appear. You will be able to search this window for specific text.

  2. Upper Right window: listing of selected data sets available on the Hera Server. There are two separate areas; a list of read-only data sets, and a list of output files that you create while running your Hera session. Output files that you create can be deleted by selecting them and clicking the "delete" button.

  3. Lower window: Displays a short description of the function of the tool selected. Try clicking on a tool in the upper left and see the description given in the text window.
On some machines you may need to resize this gui in order to see the whole thing. You will first need to click on a data set in the upper right window to select it. Then you can choose a tool in the left window. To execute the tool you just need to click on the "run" button below the tools window. When you run a tool, a parameter box will appear that you may need to fill in. The data set and data set directory should be filled in already. Any needed parameters will have a blank white space to be filled in. Parameters with default values will be grey (though these can be overwritten). The guided tutorial that follows often has suggested starting parameters. Using these parameters will help make the exercises more clear, since a bad choice of parameters can lead to confusing or unexpected results! Once the parameters are filled in you can click on "run" to run the tool. There is also a "save these parameters" button, which can be useful (so that you do not have to retype in all of the parameters, when you are varying just one, for example).

If you have any problems, comments, or suggestions regarding Hera, please use the 'Mail' button in the lower right corner of the Hera command window.

If words seem to be missing from the articles, please read this.

Imagine the Universe! is a service of the High Energy Astrophysics Science Archive Research Center (HEASARC), Dr. Alan Smale (Director), within the Astrophysics Science Division (ASD) at NASA's Goddard Space Flight Center.

The Imagine Team
Project Leader: Dr. Barbara Mattson
Curator: Meredith Gibb
Responsible NASA Official: Phil Newman
All material on this site has been created and updated between 1997-2014.
This page last updated: Thursday, 28-Jul-2005 14:24:36 EDT