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I saw a comment that there were a lot more double stars in the sky than listed in Norton's or in a GOTO scope database. I found my way to the Deep Sky database (http://www.virtualcolony.com/sac/) and a list "Double Stars With a Constallation" (http://www.virtualcolony.com/sac/star_search.html) which gives a list sorted for minimum brightness, magnitude difference and separation. I generated some lists with parameters that would not overtax my 127mm Mak, and was gobsmacked at the result. For Lyra, I got a list of 27 doubles down to mag.10 Armed with the printed list, I set about finding them in the sky. Equipment: 127mm Celestron Mak on Nexstar Goto mount, 8mm Celestron X-Cel eyepiece & 25mm Celestron stock eyepiece. Out of 18 doubles I looked for, I was able to find and resolve about 13 in a little over one hour. Sky conditions: Urban, full moon. None of them were as pretty as the bright and well-known doubles, but it was an eye-opener to discover how many were out there. I would submit that this exercise would have been impossible (or at best very frustrating and time-consuming) without a Goto mounting. All I had to do was key in the RA and Dec, and since I had used Vega as an alignment star I did not even have to swap out the high-power eyepiece between stars. I wonder if it's possible to import these databases into a format suitable for remote control of a Nexstar?

I have just posted an update to the database model obslog (in case someone might be interested ). You can find the manual, the SQL code for generating the tables, and a sample database file here: obslog - an elementary database model for logging astronomical observations I am now working to complete the auxiliary table "constellation", so I can include it in the next official release. Comments and (constructive) criticism are welcome. Also feel free to try, modify and fork. It is free and open source software ! Cheers and good luck logging your observations.

A new internet site, launched I think a couple of months ago, promises to be a comprehensive database of early refracting telescopes before the widespread introduction of the achromatic doublet circa 1775. http://www.dioptrice.com/ According to the home age, "Dioptrice is the first step toward a richer history of the telescope through an inventory and description of surviving instruments created prior to 1775 held in museums and collections around the world. The database contains information on physical objects as well as depictions of refracting telescopes in early books, manuscripts, and works of art." More information on the project is provided as follows: "After the invention of the telescope in 1608, early telescopic observations provided new views of the heavenly bodies and the sidereal universe. Though the telescope was central to the development of modern astronomy, aspects of its origin, evolution, and diffusion remain poorly understood. In particular, for early observers the ability to observe more details was closely linked to improving the optical performance of their telescopes. Dioptrice is an initiative to develop a richer history of the telescope through a census of surviving instruments and analysis of their optical properties." "Dioptrice consists of two phases of research. The first phase is the construction of a searchable database of surviving refracting telescopes created prior to the advent of achromatic lenses in c. 1775. Initial information on these instruments was gathered from direct inspection of artifacts in public and private collections, online and published collection catalogues, and correspondence with museum curators over the course of three years. The database is supplemented with images of early refracting telescopes in works of art as well as books and manuscripts, primarily from the rare book collection of the Webster Institute for the History of Astronomy at the Adler Planetarium & Astronomy Museum. The database will continue to grow as additional collections are investigated and new instruments found. This phase of Dioptrice represents a unique research tool documenting the material culture of telescopes and their representations in art. It also allows information on collections around the world to be accessed by a wider research audience and provides an avenue for the general public to explore and engage these unique scientific artifacts." "Phase two of Dioptrice involves the careful optical testing and analysis of many of the instruments in the database using adaptive optics to study optical performance, glass quality, and lens configuration. This ongoing aspect of the project will address questions of technological transfer in these instruments as well as exploring aspects of material production, diffusion, and craftsmanship." "The principal investigators of Dioptrice are Marvin Bolt (Corning Museum of Glass, Corning, New York) and Michael Korey (Mathematisch-Physikalischer Salon, Dresden, Germany). Dioptrice is curated by Stephen Case (Program for the History and Philosophy of Science, University of Notre Dame, Indiana)." As yet it seems that the project is in its early days. Unfortunately not all the thumbnails link through to more detailed information, but hopefully these will be ironed out as it develops. But in other cases, however, there is a wealth of material, such as for the c.1617 telescope in the Kunstgewerbemuseum / Staatliche Museen zu Berlin which may well be the oldest surviving telescope: http://www.dioptrice.com/telescopes/782

Dear all, I hereby present obslog, a project in which I have been working during the summer, namely a database system for storing my records as an amateur astronomer. (Disclaimer: the text below has also been posted in my astroblog: Epistulae Astronomicae). The central idea in obslog is that everything an amateur astronomer does, like visual observations, photography, variable star estimations, spectroscopy, etc., takes place during a session. A session occurs during a specific span of time, in a specific place, under a given weather, Moon phase and particularities. These properties are common to all activities that are carried on during a session and do not need to be entered more than once, that is, as a row in a table describing sessions. In the same way, activities that amateur astronomers do during a session have different sets of properties that define them, although some elements might be common. For example, all observations have a target object, are done with an instrument, which can be fitted with an eyepiece, filter, accessories, etc., and result in some kind of note, sketch or data. In principle, all this might be easily stored in spreadsheets and, in fact, this is what most amateurs do. I nevertheless chose a relational database model because it is more flexible and powerful than a spreadsheet, while being only a bit more complicated. In a relational database entities are described non-redundantly in tables and the retrieval of information is done through queries. Queries can be arbitrarily complicated and may involve information stored in many tables. Following the relational database paradigm, in obslog redundancy is minimized by defining separate tables for specific classes of activity and equipment, like session, observation, object, instrument, eyepiece, etc. Data are stored once, in only one place, and given an unique identifier. Every specific item can thus be uniquely referred to in another table if necessary, minimizing the chance of errors, and when something needs to be changed it only needs to be changed once at the place where it is stored. As it is not always possible or desirable to fill all fields, I deliberately chose to avoid the not null clause in all fields except for the unique identifier (primary key). Also following the relational database model, anything that can be calculated from stored data is explicitly avoided, for example the magnification given by a certain combination of telescope and eyepiece, which if needed can be calculated in a query. The current design of the database necessarily reflects my style of practicing the hobby: mostly observational sessions, including variable star estimations, with occasional imaging. I therefore include some tables with information from the American Association of Variable Star Observers — AAVSO that is only useful for variable star observers. Obviously, this layout might not be adequate for someone for whom imaging is the entire purpose of her/his sessions. This should not be a problem, as obslog is free software and users have the code at their disposal to make modifications to satisfy a wide variety of purposes. If you are interested, you can find obslog in the figshare repository: obslog – an elementary database model for logging astronomical observations There you can find a pdf manual, a prepackaged database file (obslog.sqlite) and the SQL code to generate it in your system. obslog is free and open source software released under Apache License version 2.0. Any comments are welcome! Good luck and clear skies! Hernán (Cinco Sauces)