The department has recently purchased a Santa Barbara Instruments ST-8 CCD and an Opto-Mechanics Model 10-C spectrograph. Both instruments were designed for use with Meade Schmidt-Cassegrain telescopes, but we have adapted them for use with the LMO 26" refractor.
The second new McCormick instrument is a professional-grade spectrograph with a CCD detector. With this device, students can measure, among other things, the compositions and Doppler motions of celestial objects. "It is very rare for undergraduate students to have access to a telescope as large as the 26-inch, and even more rare to have access to one equipped with such modern instrumentation," according to Majewski. "This unique new facility greatly enhances our ability to teach astrophysics to undergraduate and graduate students and is a great complement to our already strong pedagogical emphasis at UVa."
The new imaging camera has been designed to operate in parallel with eyepiece viewing through the telescope. In this way, students may compare naked-eye views of celestial objects to those captured by the electronic camera. Both the eyepiece and camera will be operational for the popular McCormick Public Nights."
"Even though the computer images are generally more detailed and show fainter structures than can be seen by the naked eye, there is still a romantic thrill people have when given the opportunity to look directly through a large telescope. The new parallel mode of operating the 26-inch allows the flexibility to give McCormick visitors both experiences," says Majewski.
We have on-line manuals for both the ST-8 CCD and the Spectrograph.
Both instruments have undergone testing during the Summer of 1997 for use with classes starting in the Fall of 1997. Below are some images taken with the student CCD during the test phase.
This is obviously an image of the planet Saturn seen with its rings
oriented almost edge on. This image was taken recently with the LMO 26"
and the ST-8 CCD. It is a false color image.
This is an image of M57, the famous Ring Nebula in the constellation of
Lyra. The Ring is an example of a planetary nebula, which results when
a red giant star sheds its outer envelope of gas. This is what we expect
will happen to our Sun in 5 billion years. This also is a false color
image.
This is an image of M13, a
globular cluster in the constellation of Hercules. This image was taken
with the doghouse 10" Meade and the ST-8 teaching CCD. The exposure time
was 30 seconds. Note the large amount of individual stars easily visible
in this cluster in just a short exposure. This image is in false color.
This is an image of the Trapezium
star group in Orion. The bright 'burnt in' region in the center is a group
of very bright stars. The surrounding 'fuzz' is the emission nebula associated
with these stars; it is a large cloud of gas glowing in the light of
hydrogen. This image was taken with the LMO 26" refractor and the ST-8 CCD,
the exposure time was 10 seconds.
This is a spectrum taken with the LMO 26" refractor and the Opto-mechanics
spectrograph. The spectrum is of EN Aqr, an M3 giant star in our galaxy.
Note that the overall shape of the spectrum is like that of a black body,
but in addition there are a large number of deep, broad absorption lines.
This is a spectrum taken
with the LMO 26" refractor and the Opto-mechanics spectrograph. The
spectrum is of M27, the Dumbbell Nebula, a planetary nebula in our galaxy.
Planetary nebulae glow brightly in the light of oxygen ions, and the two
large lines you see are the 4959/5007 Angstrom doublet of twice ionized
oxygen.
These are just a few examples of the types of observations that can be made with our new student instruments. We will be incorporating their use more and more in ASTR 130 (lab for non-majors), ASTR 313 (lab for majors), and ASTR 511 (lab for graduate students) in the coming semesters.