The British Astronomical Association was formed in 1890 and membership is open to all persons interested in astronomy. It has an international reputation for the quality of its observational and scientific work.
The Computing Section began in 1920. Its work is nowadays largely concerned with the preparation of the annual Handbook of the British Astronomical Association, together with data for other publications.
On this site you will find, amongst other things,
- useful observing aids in the form of applets and scripts, calculating in real time, often with a detailed graphical display;
- finder charts for currently visible comets and asteroids;
- Handbook sections which hardly change from year to year;
- background information about the Handbook and its contributors;
- history of the Computing Section.
BAA members can download a PDF version of the Handbook from the Downloads option on the logged-in Members menu of the main BAA site.
You may need to clear your browser's cache to see latest changes (in Windows: Ctrl+F5).
The charts pages (asteroids and comets) are frequently revised, so will not be listed here every time.
- 2014 Jan 17 - The latest Java update makes it impossible to run some of our applets. More details.
- 2014 Jan 2 - As 1 Ceres and 4 Vesta follow each other for much of 2014 we provide monthly combined charts for them on the asteroid charts page. These are interactive charts from which ephemeris data can be seen.
- 2013 Dec 2 - Starting with 1021 Flammario asteroid charts now have ephemeris data built in, to appear interactively as the mouse cursor moves along an asteroid track. The same will occur for comet charts from 2014 Jan 1.
- 2013 Nov 28 - Tables added showing mutual phenomena between Jupiter's satellites which begin in autumn 2014. Access is either via the Handbooks page (under additional material for 2014) or the page showing Jupiter's Galilean satellites.
- 2013 Jul 19 - Another new program, Heliocentric JD, enables variable star observers to correct their time measurements for the Earth's light time relative to the Sun in the direction of the observed star.
- 2013 Jul 15 - A new program for displaying the mean orbital elements of the major planets and some derived quantities, for any epoch.
- 2013 Jun 28 - The applets tab has been renamed "Programs (applets)". The term applets will be phased out.
- 2013 May 26 - The comet finder charts have a new interactive facility to assist observers with magnitude estimation.
- 2013 May 10 - The table of asteroid appulses has been extended with widened search criteria, agreed with the Asteroid and Remote Planets Section.
- 2013 Feb 25 - There is a new "morsel" about Julian Dates and how they are computed.
- 2012 Dec 9 - A star-hopping application can now be downloaded from the applets section, as mentioned in the introduction to Handbook 2013.
- 2012 Aug 1 - The descriptive text for the "What's observable" applet has been revised, particularly to include references to further information about the Kreutz comet search area.
- 2012 Jul 31 - The "What's observable" applet now puts the full names of objects on the detailed charts. This was particularly requested for the charts of the Kreutz comet search area. Also the general list of comets (not necessarily Kreutz) which may be added to the display is now much larger.
- 2012 Jul 31 - Another ERRATUM for the 2012 Handbook has been found - see this page.
- 2012 May 8 - A new applet showing an interactive view of the sky is aimed at making slides for educational presentations.
- 2012 Apr 30 - The catalogues page has been revised to give more information about finding catalogues online.
- 2012 Mar 21 - A small enhancement to the "What's observable" applet puts a marker at the edge of the display if an object is outside the +/-45 degree declination range, to make it more obvious that you can still click for its details. Eg, C/2009 P1 Garradd is currently at +66 degrees.
- 2012 Feb 27 - There is a new morsel, about avoiding errors with units when computing with angles.