Site Overview
The Lowell Discovery Telescope (LDT) is Lowell Observatory's flagship facility at a dark-sky site approximately 40 miles southeast of Flagstaff on the Coconino National Forest. We support both in-person and remote observing, with the latter growing significantly in popularity following the COVID-19 pandemic.
Telescope Overview
The LDT sports a 4.3-m thin-meniscus primary mirror supported laterally and axially by an active optics system (AOS). The telescope rides on an elevation over azimuth mount. The LDT's pointing model provides ~2" accuracy over the entire sky down to 6º elevation, but the mount is capable of pointing to horizon.
Presently, the telescope is configured for the Ritchey–Chrétien (RC) focus, with an effective focal ratio of f/6.1. The mount is also configured with two large Nasmyth and 6 bent-cassegrain ports; development of instruments for these would additionally require development of a tertiary mirror.
Instrument Overview
Scheduling Overview
Facility Instruments:
LMI (Optical Imager)
DeVeny (Low- to Medium-Resolution Optical Spectrograph)
NIHTS (Near-infrared Low-Resolution Spectrograph)
Visitor / PI Instruments:
EXPRES (High-Resolution Optical Spectrograph)
QWSSI (Optical Speckle Imager)
RIMAS (Near-infrared Spectrograph / Imager – Under Development)