Designed to fail? - the current state of amateur double star astronomy.

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There are not many branches of science where amateurs regularly contribute significant observations or discoveries. Astronomy is somewhat different, not least because the number of professional astronomers is relatively small and observing time at the major observatories is very limited. This leaves many areas of astronomy where amateurs can contribute and in the past measuring the orientation and separation of binary stars was identified as one example of this.

SECTION 1 - A crucial distinction: Binary Stars v's Double Stars

Two stars orbiting around their center of mass are called a binary star. Binary stars are important in astrophysics for a number of reasons - not least since orbital studies allows the mass of the stars to be determined. Various sub-types of binary star exist such as optical binaries, spectroscopic binaries and eclipsing binaries.

Optical double stars are just “line of sight” arrangements of no particular astronomical significance.

Historically it was very difficult to distinguish between the wheat (binary stars) and the chaff (double stars). For this reason the Washington Double Star Catalog (WDS) is a mixture of three types of object:

1. Binary stars
2. Double stars
3. Stars that, without further information, might fall into either class

SECTION 2 - The standard catalog

What are the main issues with the Washington Double Star Catalog as currently available through Centre de Données astronomiques de Strasbourg?

1. The most recent version of WDS available through the CDS Vizier service is more than ten years out of date (1996).
2. Inputting the double star names (identifiers) contained within this 1996 version of WDS into Simbad does not always produce a match.
3. Many line-of-sight double stars are present in the database.

What are the main issues with the updated 2006.5 varsion of the Washington Double Star Catalog?

1. Although a number of improvements have been made in this 2006.5 version the presentation method chosen makes searching the database far harder than it needed to be.
2. Inputting the double star names (identifiers) contained within this 2006.5 version of WDS into Simbad still does not always produce a match.
3. Many, if not most, of the new entries included since 1996 cannot be said with any certainty to be binary systems. Indeed it is generally agreed that a good proportion of the entries recently imported into the database are not common proper motion "pairs" at all.
4. The criteria used to decide if and when new discoveries or results will appear in the WDS catalog do not seem clear or consistently applied.

SECTION 3 - Adding data to the catalog

The current system for providing amateur astronomers with feedback and for getting their double star observations into the Washington Double Star Catalogue (WDS) is, frankly, bizarre. Since direct submission to professional colleagues is apparently frowned upon so amateur observations or discoveries have to be submitted via one of the magazines that welcome material of this type.

After submission the waiting begins. The referee's report can take anything between a few weeks and a few months and once the article has been accepted it can take anything from three to nine months for publication to take place. Most people seem to regard this wait, typical of many scientific publications, as acceptable but, confusingly, refereed publication does not guarantee acceptance into WDS. In my experience amateur astronomers are seldom if ever told when or if their results will appear in WDS.

My personal view is that the submission of results to a magazine as a pre-condition for entry into WDS is an unsustainable position in the 21st century. Submitting variable star observations can be done over the Internet and immediate comparisons with results from other observers can be made. This has the major advantages that data that is in error can be spotted easily and removed and the observer receives immediate feedback. By contrast although the WDS people doubtless do similar checks these are done months after the data was originally sent away for publication and seemingly without adequate reference to the author. I worked as a teacher for many years and I know from experience that rapid feedback and appropriate recognition are strong motivational forces. I am certainly not alone in recognising this fact - colleagues at the Minor Planet Center and the American Association of Variable Star Observers have worked tirelessly over many years to create their responsive and user-driven systems.

SECTION 4 - The WDS website, or "How not to present an on-line resource".

With so much free and consistent advice available on how to create a web site it is most disappointing that the Astrometry Department of the U.S. Naval Observatory have created a site that lacks some crucial information.

Less than five year ago amateurs were being told that " ... if the two stars are at 10" and closer we call it a double and put it in the WDS, even if it is so faint that the likely physical separation probably rules out it being a real double."

SECTION 5 - Concerns raised in the newsgroups and elsewhere.

All these issues have been raised, many times, in private emails to those involved. No reply has ever been received that dealt with the problems and concerns included on this website.

The Yahoo group Binary-Stars-Uncensored is a restricted entry group moderated by one of the stronger supporters of the status quo. The group exists - at least in part - to support the activities of the Journal of Double Star Observations and many of the articles published within the magazine are lists of double star measurements. Of course some first rate articles have also appeared within JDSO but it seems highly doubtful that a quarterly magazine would be viable without these measurement lists as "padding".

SECTION 6 - Conclusion.

One of the difficulties that faces people pushing at the boundary of "standard practice" is the tendency of some colleagues within the field of double star astronomy to interpret any criticism of the status quo as being a criticism of the people involved rather than of the systems currently in use. Instead of a free exchange of ideas the debate usually sinks to the level of name-calling or those in charge simply ignore the questions asked of them.

Everybody appreciates that many constraints exist on the WDS - manpower and money to name just two. That is called living in the real world. However the WDS does say that the catalogue is "updated nightly" so providing any amateur data was in the required format the work involved at the Washington end must be fairly minimal. Many of the measurements that are the life-blood of the WDS are provided by a pool of unpaid helpers and I think keeping such people happy and motivated should be a high priority even if it involves some inconvenience to professional colleagues. For some amateurs seeing their double star measurements in print - thanks to the efforts of the unpaid volunteers at JDSO and/or the Webb Society - is enough but I am surprised that such magazine contributors are not thanked or even informed when their material is placed in the WDS.

However there is also a substantial quantity of material that has been published in JDSO over 12 months ago that has still not appeared in WDS. If routine amateur observations have gone through the refereeing and publishing procedures required by the professionals then I think it is incumbent on these self-same people to either publish the results within WDS or to explain in detail (perhaps with a copy to the referee) why publication should not take place.

It is highly amusing to me that the scientific and astronomical rights and wrongs of the current situation have, in the main, not been discussed by those directly involved. Others shouting from the sidelines rarely know all the facts and so some, sometimes much, of what they say is incorrect. The loudest shouter and supporter of the status quo is certainly working towards his own agenda rather than the common good.