Dear Colleague,

The Astrophysical Research Consortium (ARC) is actively looking for new partners in the 3.5-m telescope and we are contacting astronomy research departments who may be interested in learning about the opportunities we offer. ARC owns and operates facilities at Apache Point Observatory which include the ARC 3.5-m and SDSS 2.5-m telescopes and the ARCSAT 0.5-m telescope.

The ARC 3.5-m telescope is a versatile, high-productivity, accessible, low-risk, state-of-the-art astronomical facility, and is in the prime of its scientific life. It has several unique and powerful capabilities:

New partners can either join ARC and become co-owners of the facilities or lease time at attractive rates for a set period.

We will also accept participation from a consortium of smaller institutions that desire to combine their resources to obtain a share of the telescope, and we will help broker such arrangements. In such cases, a consortium representative would have a seat on the ARC Board of Governors and the consortium would coordinate selection of its own set of accepted observing proposals and submit it for scheduling by the Director, in the same way current ARC partners submit their programs for scheduling.

Details on the facility can be found at and at The information posted includes a description of the instrumentation, examples of scientific results, and an overview of the site and facilities.

Briefly, the current instrument suite includes an Infrared JHK medium-resolution spectrograph (TripleSpec), an IR camera (NIC-FPS), an echelle spectrograph (ARCES), an optical long-slit imaging spectrograph, which also offers multi-object capability through use of slitmasks (DIS), an optical camera (SPIcam), a fast photometric camera (Agile), and, through a collaboration with GSFC, a high-resolution narrow-band imaging Fabry-Perot camera for which an Integral Field Spectroscopy option is under active development.

Future instruments that are currently in the planning stages include a new optical imaging camera and a fiber link to the Sloan 2.5-m high-resolution IR spectrograph APOGEE. The latter would enable use of the 300-fiber APOGEE instrument on the ARC 3.5-m telescope when the instrument is not in use for the SDSS project. Both multi-object capabilities and fiber bundle(s) are under discussion.

We also have extensive experience with accommodating guest instruments on the flexible Nasmyth instrument platform. Joining ARC would, of course, provide the new partner with a significant voice in planning our future instrumentation and in taking an active role in developing new instrumentation.

APO also hosts a 0.5-m telescope (ARC Small Aperture Telescope — ARCSAT) which we are presently upgrading for remote observing, and which may also be of interest for simultaneous observing with the 3.5-m or for separate projects that require more time but a smaller aperture. We anticipate making this telescope available for very modest cost to ARC members when it is fully operational. In addition, the NMSU 1-m telescope, also located at APO, is operated in a fully robotic mode, and outside users can request time through NMSU. Thus, we also have some small telescope access opportunities at APO.

Inquiries from institutions interested in joining SDSS-IV and the 3.5-m through a combined arrangement can also be considered.

We would welcome further discussion with you about the possibility of joining as a partner or for leasing time on the ARC 3.5-m telescope.


Rene Walterbos
Professor, Astronomy Departmental
New Mexico State University
Chair, ARC Board of Governors

Suzanne Hawley
Professor, Astronomy Department
University of Washington
Director, ARC 3.5-m Telescope
Apache Point Observatory

Bruce Gillespie
ARC Program Administrator
Apache Point Observatory