Observatory

Observing Session Checklist

Southwestern’s large research-quality reflecting telescope was donated to the Physics Department by Max Allen, a local engineer and builder who was also an amateur astronomer. This Meade LX-200 with Schmidt-Cassegrain* optics and a 16” primary mirror has a digital CCD camera for taking digital images that can be viewed and processed on a computer. This instrument is used by faculty and students for research, and programs of general interest to the public are conducted each month during the academic year.

DOME

  1. sign into log: person(s), date, time, objective
  2. open up dome observing window after removing locking pin
  3. activate electric fan to equilibrate internal and external temperature of the dome

MEADE LX200

  1. loosen the DEC brake
  2. remove and safely stow the plastic bag and large mirror cover
  3. remove finder lens caps and cap on the viewing end of the LX200
  4. attach 2” diagonal mirror lens holder
  5. attach wide angle eyepiece
  6. loosen RA brake

SET TIME AND DATE

  1. turn the power switch on the LX200 main control panel
  2. turn on the Macintosh and open the program called Vyrema, go to the file menu and use the program to reset the system clock to Local Standard Time
  3. wait for the LCD display on the telescope’s hand controller to register
    Telescope
    Object Library
  4. press the MODE key until the display reads
    LOCAL= 12:00:00
    SIDE = 14:00:00
  5. press and hold down the ENTER key until the hand controller beeps twice and then use the number keys and the E and W keys to enter the correct local time in 24 hour format
  6. (the siderial time will change automatically when the correct latitude and longitude are in memory—which they are)
  7. press the ENTER key when the computer time and the time you entered on the keypad match to the closest second
  8. press ENTER again and the display should read
    01/01/00
    _
  9. press and hold the ENTER key until the hand controller beeps twice,
  10. then enter the correct date, then press the ENTER key

ROUGH POLAR ALIGNMENT PROCEDURE

  1. set RA to 0h and lock it, then set the DEC to 90° and lock it
  2. press the MODE key until the display reads
    Telescope
    Object Library
  3. use the up and down arrow keys on the bottom right hand side of the hand controller to select “Telescope”
  4. press the ENTER key
  5. select “Align” and press the ENTER key
  6. select “Polar” and press the ENTER key.

    WARNING:: At this point the fork arm of the telescope will start to slew to an hour angle that approximates the position of Polaris for the current time and date. It is possible (and has happened with regularity) for the black serial cord connecting the fork arm to the main panel to get wrapped around the main dial and stuck between the RA dial and the fork arm.

    DO NOT LET THIS HAPPEN !!! The added resistance will cause a slippage in the worm gears and the alignment process will have to be repeated from scratch. I recommend holding this black cable in one’s hand while the telescope is slewing to Polaris (or any other time it looks as if this cable may get wrapped around the telescpe).

  7. Center Polaris in the finder using the hand controller then center Polaris in the eyepiece using the hand controller

    If extreme pointing precision is required one may switch at this point between the superplosal eyepeice and a smaller eyepeice. One may even go as far as to use the luminated retical eyepeice, but this requires refocusing the telescope and usually one can use the 16 mm eyepeice and achieve excellent results.

  8. to center an object use the NSEW keys to move the telescope
  9. the speed setting of the motor drive is adjusted via the Slew, Find, Center, and Guide keys
  10. red indicator lights indicate the current setting
  11. the focus can be adjusted by holding down the focus key while pressing the up or down arrow keys (the speed of the electronic focuser is proportional to the speed setting of the LX200’s motor drive. NOTE:: The electronic focuser is currently disconnected from the telescope because we have found it easier to focus manually.
  12. press the ENTER key. The telescope will automatically slew to a second alignment star. When the telescope stops, center the star listed on the hand controller display using the the hand controller.
  13. press the ENTER key
  14. IMPORTANT: Do NOT unlock the RA or DEC after setting the alignment. If you do the telescope will literally not know up from down.

MAKING OBSERVATIONS

Method One
    1. look up the number for the object you wish to observe
    2. use the M, CNGC, and STAR keys to select an object type for observing
    3. enter the number of the object
    4. press ENTER and then GOTO
    5. the telescope will automatically slew to that object
Method Two
  1. to slew to a particular set of coordinates hit the MODE key and the RA and DEC will appear on the control panel screen
  2. use the NSEW keys and the speed selection to slew to any part of the sky

    This method is useful if you are doing research on stars that are not listed under any of the catalogues in the control panel’s database (which only consists of a few thousand stars). We have used this method while researching RR Lyrae variables.

SHUT DOWN PROCEDURE

  1. turn off the telescope power switch
  2. unlock the RA and DEC brakes
  3. replace the corrector plate cover
  4. replace all lens caps
  5. align telescope vertically by setting RA to 0h and setting DEC to 30°
  6. set RA and DEC brakes
  7. replace large plastic bag
  8. safely stow the eyepiece and eyepiece holder
  9. close observing window carefully and replace locking pin
  10. rotate observing window away from oncoming storm fronts (if applicable)
  11. Sign out log: summary of what was done, problems found/fixed, signout time
  12. Computers off & lights out

DOUBLE CHECK THAT THE DOOR IS SECURELY LOCKED WHEN YOU LEAVE

document last revised 6/5/98 by Andrew Kinard