Remote Login to the Haystack Observatory Pointing Computer

 

This Quick-Start tutorial assumes the user is operating the telescope from remote terminal outside of Haystack and with a UNIX/Linux operating system.

1. Obtaining a user password and data processing disk space
User passwords must be obtained from the observatory to operate the 37-meter telescope. Passwords are usually issued for a limited time to allow for planned observation and subsequent data processing. Disk space usage is limited only by the size and scope of the project. The observatory requires the user to follow certain naming conventions for directories and sub-directories to allow the system administrator to manage the available space and make summary judgements when there is need to clear the disk.
For Example:
Submitted Umbrella Schedules should have a .skd suffix.
Source List files should have a .lst suffix.
The users will be informed when the data area will be cleared and archived but we strongly urge all users to format and port their data at the time of their observations since we do not guarantee the availablity of their working data files for any extended period nor can we gaurantee timely retrieval of their raw data from archive tape.
2. Logging In
  • Step #1 -- Set UNIX/Linux environment variables for Haystack Operations

    • There are several environment variables that need to be set in your computer to display properly the output of your Haystack observations. You will first need to set permissions for the Haystack computers GAUSS and FOURIER to write to your X-server.

    xhost fourier.haystack.mit.edu
    and
    xhost gauss.haystack.mit.edu
  • Step #2 -- SSH login to fourier.haystack.mit.edu

    ssh -Y fourier.haystack.mit.edu

    Using your assigned username and password

    SSH is the only way to access Fourier. Shell scripts designed to setup DISPLAY environments for graphics output and links are tailored to the secure shell login.

  • Step #3 -- After logging in, at the fourier xterm window prompt, type:

    user@fourier> Xterm
    This command will set display environments on Fourier and Gauss to point to your terminal. The xterm window that opens on your screen is the window in which you should type the next command. Position the new window to the lower left of your monitor screen.

    If the "Xterm" command fails to open a new window or returns an error message, there may be a problem with the ability of the Fourier script to read the IP number from your machine.This failure can have several causes. (Examples: Your Internet Service Provider has a problem with it's IP-number directory. Your local network has firewall settings in place that will block certain transmissions from our site.) Contact Haystack if you have any trouble opening a Fourier window on your computer.

    If you need to setup variables to display Multiple-Drift-Scan output.

    user@fourier> setenv PGPLOT_DIR /usr/local/pgplot/
    user@fourier> setenv PGPLOT_DEV /xserve
3. Start the Umbrella Program
At the New X-window system prompt type:
user@fourier> US
This will open two additional X-windows (one titled Xterm Log and the other Xterm Umbrla) and a TCL/TK window entitled WatchThis. The Xterm Log window reports output from two telescope control programs Upoint and Dop. The Xterm Umbrla window is the user interface to the telescope using the Umbrella script program to send discreet commands and automatic schedule files to the telescope control programs.

4. Enter Setup Parameters into Umbrella and Initialize Pointing
At the Xterm Umbrla window, enter the setup parameters for your observations. The parameters can be entered as a defined Umbrella macro or as discrete Umbrella primitives. The user should set the minimum number of primitives listed below and it is suggested that the user list the primitives in the order given (See the Umbrella manual for detailed explanations of each primitive).

The following commands will setup a Single Channel, Beam Switched, Continuum observation. Please enter the Umbrella primitives IN THE ORDER LISTED (comments after the # sign).

Umbrla> Project = YourProject

Umblra> Maintenance = Off

Umbrla> Frequency = Your frequency # (in KHz !)

Umbrla> Bandwitdth = 160 # (For Continuum 160 MHz)

Umbrla> Beamswitch = On # (For 18-24 GHz observations, Beamswitch = OFF! When Beamswitch is ON, CDPMode should be "M")

Umbrla> CDPMode = 1M # (1M = 1 channel modulated calibration (Use 2, for 2 ch. and U, for unmod. i.e. Total Power or Frequency Switch))

Umbrla> Sourcelist = /home/pas/point.lst # (or your own source list)

Umbrla> Source = planet or source # (Inserts coordinates into Upoint)

Move your pointer to the 'Umbr' stop lights in the WatchThis window and click the left mouse button. This will open the display of source coordinates and telescope position as well as other Umbrella settings. The Local Sidereal Time L.S.T. is also displayed. A right mouse button click will close any WatchThis window.

The 37-meter telescope pointing program is now initialized.

You are now ready to begin your Observing Program!