Raspberry Pi and Mathematica Control Telescopes

The single board computer, the Raspberry Pi or RBPi is a versatile device helping youngsters learn computer programming. Its advantages do not stop there, because many hobbyists and DIY enthusiasts also use the RBPi for their numerous innovative projects. For example, Tom Sherlock, an amateur astronomer, has put the RBPi to good use for controlling his telescope. Along with the RBPi, Tom uses Mathematica and the Wolfram language for his telescope control.

Amateur astronomers such as Tom use Mathematica in their hobby to process and improve the images they take of planets and nebulas. They use the Wolfram language to control their astronomical hardware. This consists mainly of controlling the drive on the telescope mount, as this is necessary when automating an observing session.

The process is an important one for the amateur astronomers who use their computerized telescopes for hunting down transient phenomenon such as supernovas. Existing software can take care of the several tasks required by astronomers such as locating objects, managing data and performing image processing, However, automating all the various tasks that an observation session needs, is a great help.

Mathematica is a very useful tool for astronomers. It helps in automating and unifying many of the above operations. Within Mathematica, you have a huge amount of useful astronomical data, which includes the coordinates of several thousand planets, asteroids, galaxies, nebula, and stars. The image handling and processing capability of Mathematica is extremely useful when processing astronomical data.

Tom had earlier interfaced with telescope mounts using an existing library of functions known as ASCOM, a powerful tool for driving domes and filter wheels, mainly associated with astronomy. However, ASCOM has to be pre-installed on a PC and therefore, is rather limited in its use. Using Mathematica allows one to drive the telescope mount directly from any platform and does not need any special setup.

According to Tom, most telescope mounts follow one of two serial protocols for their control. These are the Celestron NexStar protocol or the Meade LX200 protocol. Many non-Meade telescope mounts, such as those from Astro-Physics and Losmandy, also follow the LX200 protocol. Those produced by the Orion Atlas/Sirius family of computerized mounts follow the NexStar protocol just as the Celestron telescopes and mounts do.

The LX200 protocol requires the right ascension (RA) function specified by a string such as HH:MM:SS and the declination (Dec) by a string in the form of DD:MM:SS. These are the basics for slewing the telescope to a target at coordinates specified by the RA and the Dec strings.

You will need an inexpensive USB-to-Serial adapter for creating the RS232 port that the RBPi does not normally have. You also need a small wireless network adapter that fits in the RBPi USB socket. As RBPi uses the Linux operating system, it is easy to use the Wolfram language code for controlling the telescope through the serial port. Additionally, the RBPi can be networked wirelessly. That makes it possible to control it from inside the house, necessary when the weather outside is cold.