Freeware from Sky & Telescope

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.

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 Adobe Reader, 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 S&T Basic Programs listings). The program is a 32-bit application (Windows 95 and higher).

After you download mp201.zip (3.0 megabytes), unzip it and run setup.exe to install the software. (To extract the files, use an uncompressing utility, such as 7-zip or StuffIt Expander). 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). If you have any questions about the program, you can contact Rios by e-mail at [email protected].

Binoplan

In the Telescope Techniques department in the July 2002 issue of Sky & Telescope (PDF of article) Glenn LeDrew showed how to make a pair of right-angle, correct-view binoculars. The article features a DOS program called Binoplan that calculates the spacing of the various optical elements and shows on-axis and off-axis vignetting. You can download it here. Be sure to select "Save program to disk" when prompted, and unzip the file using an uncompressing utility, such as 7-zip or StuffIt Expander.

Cool

In the Telescope Techniques department in the January 2002 issue of Sky & Telescope (PDF of article) Alan Adler explains how forcing airflow over the primary mirror of a Newtonian reflector dramtically improves performance. The article features a DOS program called Cool that models the effects of different thermal situations. You can download it here. Be sure to select "Save program to disk" when prompted.

Flex

In the Telescope Techniques department in the November 2000 issue of Sky & Telescope (PDF of article) 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 download here. Be sure to select "Save program to disk" when prompted, and unzip the file using an uncompressing utility, such as 7-zip or StuffIt Expander.

Sec

In the Telescope Techniques department in the August 2000 issue of Sky & Telescope (PDF of article), associate editor Gary Seronik and telescope maker Alan Adler discuss how to determine the optimal size of a secondary mirror for a Newtonian telescope. Adler provided a helpful DOS utility called Sec, which you can download here. Be sure to select "Save program to disk" when prompted.