A Monster Telescope at Happy Jack
July 19, 2012 -- The Discovery Channel Telescope (DCT) is complete and the "First Light Gala" -- where the first images from the DCT will be showcased -- is being held at Lowell Observatory on Saturday, July 21.
The huge, 4.3-meter telescope -- at an elevation of 7,760 feet (2,370 meters) atop a cinder cone in Happy Jack, 40 miles southeast of Flagstaff, Ariz. -- is a joint $53 million project between Lowell Observatory and Discovery Communications. The telescopic monster took nine years to construct.
After first light, the DCT is expected to be fully operational later this year. It is the fifth-largest telescope in the continental United States.
Lowell Observatory astronomers will use the DCT to examine some of the most vexing mysteries of the solar system by probing deep into the Kuiper Belt, beyond the orbit of Neptune. They also aim to expand our knowledge of the universe, examining how dwarf galaxies evolve. It will observe the universe in two wavelengths: optical and near infrared.
Naturally, Discovery News will be giving our readers continual coverage of the science coming from the DCT!
But before the DCT begins its long career of science and discovery, take a look behind the scenes of Lowell Observatory's "most exciting adventure ever."
Many thanks to Lowell Observatory's Media and Communications Coordinator Tom Vitron for his help in providing the photographs and information contained in this slide show.
The DCT Mount
In 2010, the DCT mount was completed. This structure supports all the optics and instrumentation for the telescope inside the 85-foot (26-meter) -tall telescope enclosure.
The DCT's Eye
The primary mirror is hoisted up to the observing level of the telescope facility ahead of being installed to the mount in August 2011.
The 4.3-meter primary mirror weighs 6,700 pounds (3,000 kg) and took three years to polish at the University of Arizona's College of Optical Sciences before it was delivered to the site in June 2010.
This is a view of the back end of the primary mirror as engineers worked to secure it to the mount. "Active optics" actuators can be seen attached to the back of the mirror, a system that allows the mirror's surface to be distorted, fine-tuning its focus.
Secondary Mirror Aluminization
The DCT is a Cassegrain telescope that uses two mirrors to focus astronomical objects. This is the 1.4-meter secondary mirror in the aluminization chamber on Dec. 19, 2011, before being attached to the mount.
Light will bounce off the primary mirror and then to the secondary mirror, at which point it will be focused into the "instrument cube" fixed to the back of the primary. The DCT uses a type of focus called the Ritchey-Chrétien, making the telescope highly flexible for a range of astronomical targets.
The secondary mirror may not be as heavy as the primary, but weight is still a concern. As shown here, the circular and hexagonal shapes correspond to sections of the glass that have been removed. Even after this step, the secondary mirror still weighs in at 473 pounds (215 kilograms).
In Its Mount
The secondary mirror as seen mounted to the telescope on Feb. 13, 2012.
On Feb. 13, 2012, the instrument cube was bolted to the back of the primary mirror. The cube "houses a suite of instruments that astronomers can use to investigate diverse aspects of our universe," according to the Lowell website.
Initially, the cube will contain three instruments:
- Large Monolithic Imager (LMI) - Near Infrared High Throughput Spectrograph (NIHTS) - DeVeny Spectrograph
The cube was designed by Ralph Nye and built in-house at Lowell. It can house up to five instruments, boosting the flexibility of the DCT to accommodate a broad range of astronomical studies at any one time.
Opening Her Eyes
Construction of the DCT was officially completed when the instrument cube was attached to the primary mirror on Feb. 7. Since then, the telescope has been undergoing commissioning.
Preliminary observations have been made by Lowell Observatory astronomers and the DCT is operating "extremely well," so far reaching an image quality of 1 arc second. The active optics system will further improve the resolution.
In this photograph, taken by Len Bright, the telescope enclosure is open, allowing the DCT to carry out observations. The moon glows brightly overhead.
Let the Science Begin!
As we move closer to "first light," Discovery News will be keeping close tabs on DCT research. But for now, we wish Lowell Observatory astronomers clear skies and the best of luck for the completion of commissioning of this awesome project!
INTERVIEW: Unlocking dwarf galaxy mysteries with the DCT -- Discovery News talks with Lowell Observatory astronomer Deidre Hunter.
For more information on Lowell Observatory and the Discovery Channel Telescope, visit the Lowell website.