Remote Observing Manual

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This manual documents the remote observing operations of Shared Skies. It covers the basic elements of all of the telescopes available remotely, and provides links to information about robotic observing and data archives. Other shorter pages are available as well. Please check the index for those.

Overview

System Architecture

Each telescope, its instruments, and its enclosure are controlled by a single computer system connected to the hardware. For different instruments there are other network components for power control and live video. The telescope operator and the observers do not have to be on site because these components are accessible remotely, either through the Internet by secure login and encrypted transmission, or through servers that limit functionality while insuring safe reliable, largely robotic, operation.

Remote Observing

In remote observing use, the telescope may have an operator on site and an observer off site, or it may be operated entirely by an off site observer-operator. In the latter case, when a fast network with low latency is available, the observer can have very effective control of the telescope in real time. Under less favorable conditions, the observer may make use of scripted operations and use a server on the high speed network to take on more automatic control of the system. Fully robotic operation based on queued requests is planned for some of the instruments in our network, but is not yet available.

Each telescope with its instruments and enclosure is under the control of a single computer system that is running INDI, an flexible instrumentation server protocol that accommodates several devices and clients simultaneously. In this way the observer may have control of the telescope while the operator stands by and monitors events, or the operator may take control as needed while the observer works with the data pipeline. Indeed, the "observer" may simply be another server on the network placing requests to the INDI server at the telescope. The essential software components that enable this process are

XEphem: an astronomical ephemeris, interactive sky map, and instrumentation interface

XmTel: a telescope control panel

XmCCD: a camera and filter wheel control panel

ds9: interactive image display spawned by xmccd

XmGuide: an autoguider controlpanel

XmDome: a dome rotation and shutter control panel

INDIServer: the remote server

Drivers: ccd, dome, tel, guide or others that talk to the server


All of the clients (XmTel, XmCCD, ...) are simply user interfaces to the INDI protocol. XEphem has a "control panel" that offers full access to the commands enabled by the hardware drivers, but it is not as convenient to use as the the individual panels. (At this time xmguide and xmdome are not available in indi versions, but their functions are handled by xephem.)

The server system is accessible on the command line with getINDI and setINDI issued on a system which has access to the port on which indiserver is running. With these commands a number of scripted utilities have been built to handle routine tasks such as starting the observations or running a sequential queue of images.