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Tenagra Observatories Supernova Search Adopts ASCOM Tools
(see the News Center for more info)

Puckett Observatory Supernova Search Adopts ASCOM Tools
(see the News Center for more info)

Welcome to the home base for ASCOM, ASCOM-Standards.ORG. ASCOM and this web site are devoted to promoting the use of open scriptable tools for amateur and educational astronomy. In order for amateur astronomers to generate useful scientific contributions and conduct experiments of their own, today's observatories need automation tools. The ASCOM initiative is devoted to promoting the technology base that will make this vision a reality.

The ASCOM logo is your assurance that a product meets a set of minimum standards for quality, interoperability, and use with Windows scripting and programming tools. If you see this logo on a product's package or web site, you can rest easy that its behavior is consistent and it can be used in combination with other ASCOM-capable products as part of your research and observing setups.

December 1998 saw the beginnings of ASCOM in a press release and an example of the technology of an open scriptable tool, DC-3 Dreams' Astronomer's Control Panel. Since then, several other companies have joined the initiative and either added or used open scriptable interfaces. Expect this trend to continue as the benefits of software components and standard scripting languages move into the mainstream of scientific amateur astronomy.

Scientific Amateur Astronomy

• Astrometry of asteroids and comets
• Photometric studies of variable stars and asteroids
• Spectroscopic studies of stars and supernovae.

• A robotic telescope
• A CCD camera
• A powerful personal computer

Software Transformation

Today's amateur astronomy software is largely aimed at visual observers and astrophotographers (people who take images for art rather than science). Programs are large monolithic packages such as planetariums and image processing programs with feature-rich user interfaces. There are also a number of specialized science packages for astrometry and photometry.

In order to provide tools for research, we need to turn this model inside out. Instead of monolithic programs, packages and suites, we need tools that implement a few closely related functions very well, and which can be laced together with scripts on the order of an Excel macro. This gives amateurs a degree of flexibility that even professionals don't have.

Riding a wave created by Microsoft, ASCOM defines high-level objects that represent instruments and complex calculations, and exposes these objects to any scripting language supported by the ActiveX scripting system that is now a standard part of Microsoft operating systems. For example, using ASCOM, the following ficticious code might point a scope to a given set of equatorial coordinates in the familiar hh:mm:ss and dd:mm:ss formats:

    Scope.ObjectRightAscension = Util.Hours_HMS("06:09:57")
    Scope.ObjectDeclination = Util.Degrees_DMS("+20:33:53")
    Scope.SlewToCurrentObject

There are no references to the particular scope in use, the protocols needed to actuate the scope and monitor its position, the connection between the computer and scope (serial line, SCSI, USB, etc.), or anything else particular to the scope itself. In the snippet above, the ficticious objects used are Scope and Util.

Open Source vs Objects and Scripts

Many OpenSource programs are designed with one thing in mind, and then pounded into another form by someone unrelated to the original developer. The result is often a "house that Jack built" that only approximates the solution and is difficult to understand and maintain. And there may be many variations on the original theme, each of which is a separate code base.

On the other hand, a developer who is proficient in tool design has flexibility in mind from the outset. The software is designed from the ground up to accomodate a wide variety of applications by exposing interfaces to its capabilities. By combining components and their objects, end users can build endless types of applications with relatively little code. Most of the core functionality is wrapped into the components, which are maintained and supported by their developers.

Standards Work

ASCOM does not preclude programs from supporting other non-object schemes (such as shared-files) for interoperating. It does, however, prescribe specific requirements for Automation/ActiveX object usage and serving.

The ASCOM Two Phase Plan

The second phase, which began in mid 2000, is an evolutionary one. The goal is to have standard core interfaces to various types of components (a standard "telescope", a standard "camera", a standard "focuser"etc.), along with a variety of proprietary enhanced interfaces. As more and more astronomy software vendors move to support ASCOM, certain core interfaces will become the de-facto standard. It is hoped that the process will be one driven by technical excellence and not big marketing dollars (as is often the case in mass markets). Since we're dealing with people that are of above average sophistication, it's a good bet that they will gravitate toward the most powerful and useful interfaces rather than the most aggressively promoted.

Once we have evolved to this point, the transformation will be complete. Amateurs will have the software equivalent of the standard 1.25" or 2" eyepiece -- software of varying capability and price, and which supports the standard or "base" interfaces plus special value-added capabilities unique to each product. Scripts written to the base interfaces will be interchangeable between amateur observatories, a holy grail not attained in the professional community.