The astronomy-related utilities listed below have been featured in Sky & Telescope and are available free of charge for personal use. This software is provided 'as is,' and without any warranty or support.

The software features five pilot aptitude training modules for UK Pilot Aptitude screenings, six for a BA test preparation, eight reasoning tests, four math. All customers of this software will receive a complimentary special keypad with their order (download customers are asked to provide an address for a free postal delivery).

When you click on each link below, you'll go to a page that explains what the software does, shows a sample screen, and links to the downloadable file. Where applicable, we also link to a PDF of the corresponding article. To read the PDFs, you'll need, which is available at no cost for most computers. Mars Previewer II — An interactive map for Mars observers. Binoplan — Design specs for right-angle, correct-view binoculars. Cool — Determine the cooldown time of a Newtonian reflector. Flex — How to stress a spheroidal mirror into a paraboloid.

Sec — Find the optimum size of a Newtonian's secondary mirror. Mars Previewer II Leandro Rios, an amateur astronomer in Argentina, created this handy utility for Mars watchers. Rios based his freeware program — which displays the central meridian and angular size of the red planet for any date and time — on the algorithm used in MARS.BAS (in the listings). The program is a 32-bit application (Windows 95 and higher). After you download (3.0 megabytes), unzip it and run setup.exe to install the software. (To extract the files, use an uncompressing utility, such as or ). NOTE added July 3, 2003: We obtained our copy of mp201.zip directly from the author, months before a virus-infected copy was posted on AstronomySight.com and publicized by Astronomy magazine.

Our copy of mp201.zip is certified virus free! When you run Mars Previewer, make sure you enter dates in DD/MM/YYYY format and set your time zone relative to Greenwich Mean Time (positive numbers to the west, negative to the east).

Download Autocad 2008 64 Bit Full Version. If you have any questions about the program, you can contact Rios by e-mail. Flex In the Telescope Techniques department in the November 2000 issue of Sky & Telescope () Alan Adler described a revolutionary way of shaping telescope mirrors that circumvents much of the labor needed to grind a paraboloidal mirror. Adler took a spherical mirror and flexed it to produce a paraboloid. The article features a DOS program called Flex to simplify the process, which you can. Be sure to select 'Save program to disk' when prompted, and unzip the file using an uncompressing utility, such as.