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Observing Titan with IRTF/SpeX

Thanks for 3 great Titan seasons!!! Now, on to the fourth!

  • Read the paper "Storms in the Tropics of Titan" published in Nature
    This paper reports on a huge cloud system detected in Titan's tropics with IRTF and subsequently observed with Gemini

  • Read the paper "Seasonal Change on Titan Observed with IRTF/SpeX" submitted to the Astronomical Journal
    This paper covers the first 2 years of Titan cloud monitoring

  • Read the paper "Discovery of Lake-Effect Clouds on Titan" submitted to Geophysical Research Letters
    This paper incorporates Cassini, Gemini and IRTF data to understand a new cloud phenomenon on Titan

    Nightly Titan Coordinates (J2000)

  • 2009-Nov-12 15:09UT (5:40AM HST) -- 120753.37 +012351.6
    **Titan can be observed anytime after 15:09UT (5:09AM HST)
    click for diagram showing Titan's position relative to Saturn

    HD 106116 -- 121228.84 -030504.1

    Observing Instructions

    • The basic outline:

    ***I am Guest21***
    Please focus the telescope if it has not been done in the past hour or you have any reason to suspect it may be out of focus.
  • 1. Take spectra of the calibration star (HD 106116) using "schaller_compstar" macro
  • 2. Take spectra of Titan using "schaller_titan" macro.
  • 3. Do calibrations with "schaller_cal_sxd_1.6"

    The details:

    1.
  • Execute the macro /macro/bigdog/observer_macros/schaller_compstar
    (This macro changes everything to the correct settings (sxd, 1.6'' slit, etc)
  • Slew to Calibration star HD 106116.
  • Check to make sure the paths for the autosave on bigdog and guidedog are guest21/UTdate (this should be done automatically when you sign in as guest21)
  • Take an image of the star with guidedog (in the GuidedogXUI "Obs","Basic", press go)
  • click on "Auto Guidebox Setup" located on the right side of the guidedog xui (this will draw the A (top) and B (bottom) guide boxes on the slit)
  • Move the star into box A by placing the cursor on the star, holding down the shift key and the center mouse button and drawing a line from the star to the center of box A
  • Now click on "offset telescope" (which is in the guidedog dv window under the "tcs offset" tab
  • Start guiding: Switch from "basic" to "slow.gd", press go
  • Take spectra of the star (press go on bigdog) (takes ~3.5 minutes)
  • Remember to stop guiding when spectra finish
  • put mirror in and set the crosshairs

    2.
  • Slew to Titan
  • Execute the macro "schaller_titan"
  • perform the same procedure above to get Titan in the slit and start guiding on it but with one exception - after Titan is in the slit, turn the guidedog autosave to "on". I like to keep the guider images for Titan just to have a reality check in case anything looks funny (it ends up only being about 60 images or so)
  • Take spectra of Titan (press go on bigdog) (takes ~5.3 minutes)
  • Remember to stop guiding when spectra finish

    3.
  • Perform calibrations by executing the macro "schaller_cal_sxd_1.6" (takes ~2 minutes)
  • That's it!