Mark Slade Remote Observatory (MSRO)–Wilderness, Virginia

Observatory Status: Operational!

South View of Observatory

Director: Myron Wasiuta
Assistant Director: Jerry Hubbell
Staff Astronomer: Lauren Lennon
Location: +38 20’ 02” -77 42’ 39” West Longitude Altitude 300’

Description of Facility

The Mark Slade Remote Observatory (MSRO) is an astronomical observatory made possible by generous donations from the estate of Mark Slade, the Rappahannock Astronomy Club, and private individuals in the Fredericksburg, VA, region.

Other sponsors include Field Tested Systems (, which donated spectroscopy instruments and software, and AstroFactors (, which donated discounted QHY camera systems. The primary commercial sponsor is Explore Scientific, LLC (, which has loaned, for long-term use, the primary/secondary OTAs, the telescope mount, and mount control systems. Jerry Hubbell, Vice President of Engineering for Explore Scientific, provides primary service on all observatory systems and equipment.

The MSRO is a modern, state-of-the-art facility using the latest in low-cost, high-value astronomical instrumentation. Its mission is to serve as both a training and research facility for anyone interested in astronomy and astronomical research. It is available for use by members of the Rappahannock Astronomy Club, local high-school and college students, and other interested amateur astronomers in the United States and in other countries.

The MSRO is operated by the MSRO Commission, which also oversees funding, approval of observation requests, coordination of observing schedules, and development of observing plans. The day-to-day operation and maintenance of the observatory, scheduling of approved observation requests, and training of users are the responsibilities of the MSRO Director and Assistant Director…

To keep up to date on the latest activities of observers using MSRO, please visit the MSRO Facebook page.

Primary Telescope—The primary optical instrument is an Explore Scientific® 6.5-inch FPL-53 165 Air-Spaced ED APO Carbon Fiber f/7 refractor that is configured with a 3-inch 0.7x focal reducer/field flattener and has an effective focal length of 852 mm at f/5.2. The CCD camera mounted on this telescope is a QHYCCD QHY163C One-Shot-Color (OSC) camera (4/3-inch, 16-megapixel CMOS chip, 4656×3522 w/3.8-micron pixels). This camera has a plate scale of 0.92 arc-seconds/pixel. The field of view (FOV) is 71.4×54.0 arc-minutes. The camera has a six-position QHYCFW2-small filter wheel attached with open, luminance, red, and V-band, and blue filters for specialized imaging and photometric measurements. The open position allows for wide-field (1.2×0.9 degree), full-color imaging of deep sky objects. A 200-line-per-millimeter (lpmm) spectroscopic grating with an effective resolution of about 13 angstroms/pixel is provided. A special filter called an Engineered Diffuser™ produced by RPC Photonics is installed in the filter wheel for use in obtaining data for very-high precision photometry on variable stars, minor planets, and exoplanet transits.

Secondary Telescope—The secondary optical instrument is an Explore Scientific® 4-inch FCD-100 102 Air-Spaced ED APO Carbon Fiber f/7 refractor that is configured with a 2-inch field flattener and has a focal length of 714 mm. The camera mounted on this instrument is a 4/3-inch, 16-megapixel CMOS chip QHY 174M-GPS monochrome camera (1/1.2-inch, 2-megapixel 78% QE CMOS chip, 1920×1200 w/5.86-micron pixels). This camera has a plate scale of 1.69 arc-seconds/pixel. The FOV is 54.0×33.9 arc-minutes. The camera is equipped with an internal GPS receiver that provides high-precision timestamps (< 1 ms error) on each image when doing single-frame and video imaging.

Instrument Capabilities—Minor planets and stars of magnitude 17 can easily be observed with the primary telescope. Astrometric (position) measurements of minor planets are possible with a typical error of 0.15 arc-seconds RMS. High-precision photometric measurements can be obtained down to < 0.005 mag (5-mmag) RMS at magnitudes brighter than 10th magnitude. The camera system installed on the secondary telescope allows high-precision time measurements of asteroid occultations and other time-sensitive measurements. The placement of the MSRO facility allow observations at declinations between −40 and +70 degrees. Local horizon limits restrict viewing at certain Right Ascensions (hour angles).

Telescope Mount—The telescope mount is a Losmandy® G11 with the Explore Scientific® PMC-Eight mount control system. The Explore Scientific® Telescope Drive Master (TDM) drive correction system is also installed on the mount to provide precision tracking to less than 1 arc-second RMS (typically 0.4 arc-second RMS). This instrument allows unguided exposures of up to 5 minutes (300 seconds). Typical 300-second star images at the imaging scales are 2 to 3 pixels FWHM (less than 4 arc-seconds).

Other Instruments, Computer, Software, Resource Documents—Other available instruments include a 2.5-inch Moonlite Precision Focuser System; FLIR® Point Grey Flea3 GigE high-speed video camera for lunar and planetary imaging; a ZWO ASI120MM CCD camera, which serves as a wide-field webcam to observe the instrument while in use; and a GPS receiver and NMEATime® software installed on the observatory computer system, which provide a precision time reference accurate to 10 ms when imaging minor planets.

The main computer in the observatory is remotely controlled using the desktop sharing program TightVNC ( Maxim DL™ V6 Pro is used to control and operate the observatory systems, telescopes, and cameras. Star charting and telescope pointing are accomplished using Cartes du Ciel V4.0. Astronomers using the MSRO can perform astrometric, photometric, and spectroscopic measurements. Software available to MSRO users includes Astrometrica, RSpec™, Registax V6, CCDInspector™, and Nebulosity™ 3. Various charting programs are available, including Virtual Moon Atlas 6.0. Documents available include Photographic Lunar Atlas for Moon Observers by Kwok C. Pau, Photographic Moon Book by Alan Chu, and Exoplanet Observing for Amateurs, second edition (plus), by Bruce L. Gary. Other miscellaneous resources are also available on the computer.

Gaining Access to the MSRO

You must be a member in good standing of the Rappahannock Astronomy Club to request time as an observer. You can find membership information here. There are three categories of users on the MSRO:

  • MSRO Guest Observer: This is the easiest way to obtain observations. This person does not actively control the observatory but can watch online while the Director, Assistant Director, or one of our fully trained MSRO astronomers makes the observation for the guest. The data obtained are then transferred to the guest observer via remote file transfer. Alternatively, if the guest does not want to be present while the observation is made, the observer will be notified when the data are ready for transfer.
  • MSRO Observer in Training: This is someone who wants to eventually operate the observatory unsupervised. During training, the observer is supervised by the Director, Assistant Director, or one of our fully trained MSRO astronomers. During training, the observer is sequentially tasked with operating more of the observatory functions until full proficiency is obtained. After a final checkout by our Director or Assistant Director demonstrating proficiency, the Observer-in-Training becomes a fully credentialed MSRO Observer. To aid in understanding the startup procedure, you can review the Startup Video.
  • MSRO Observer: This observer has completed the MSRO Observer in Training Program and has been found fully capable of performing those tasks necessary for operating the observatory by both the Director and Assistant Director. This observer is granted full access to the operation of the MSRO unsupervised.

If you are interested in the Mark Slade Remote Observatory fill out the MSRO contact page and submit to send it to the Director.

Explore Scientific® provides a way to not only experience using the MSRO as a guest observer but offers an extended 3-hour observing session one-on-one with the Assistant Observatory Director as your personal guide. Your purchase of this experience provides a generous donation to the Mark Slade Remote Observatory, which helps us continue to offer this resource to high school and college students and to amateur astronomers, not only in the United States but also in other countries.

There is no charge for Rappahannock Astronomy Club members to use this observatory. However, the MSRO Commission and Staff appreciate any donation you wish to give. Donations help us to maintain, operate, and upgrade the observatory instruments and facilities as needed. Please contact the Director via email for details on how to donate.