Interstellar overdrive - Linux and astronomy
by Richard Hillesley
"The untold want by life and land ne'er granted, now voyager sail thou forth to seek and find." - Walt Whitman
Desktop astronomy has become more accessible over the last few years as hardware and software have come down in price. For an outlay not much greater than a top of the range PC it is possible to put together a CCD powered telescope that is more than adequate for hunting comets or prospecting for asteroids which are still popular pastimes among amateur astronomers. This optical hardware can be augmented by a substantial range of free software to process the raw images and guide amateur astronomers on where to look and what to see.
Source: NASA, ESA, J. Hester Arizona State Uni. At a more prosaic level, anyone with an appropriately enabled smart phone can sit beneath the stars and view a labelled Google Sky Map that uses Android, GPS, compass data, date and time to fix your place on earth, and learn the names of the stars.
Anyone with a laptop can access the vast star catalogues that are made available across the net, and view the skies through software packages such as KStars, Stellarium or XEphem, which allow the user to scan the celestial landscape from any perpective on earth in the comfort of their living room. Stellarium and KStars are licensed under the GPL. XEphem is open source and free for non-commercial use.
Each of these packages can be coupled through a laptop to a telescope, and with the use of filters, dedicated CCD (charge-coupled device) cameras and GOTO technologies, anyone with access to a relatively modest telescope can hope to sidestep the negative effects of light pollution and observe and photograph asteroids and planets, distant nebulae and faraway moons in the kind of detail that not so long ago was the preserve of large scale observatories.
Astronomy is the oldest of the sciences. Observing the heavens and our place among them has been a preoccupation of mankind since the beginning of time. The need to understand and interpret the stars was a pivotal feature of the religion and philosophy of the ancients from Stonehenge to Hipparchus, from the Babylonians to the Chinese, and played a big role in the growth of mathematics and the sciences.
On a philosophical level astronomy provided a window into the mechanics of life and the universe. On a practical level astronomy gave the means to navigate by land and sea, to construct a calendar and to tell time. These approaches come together in the Antikythera mechanism, "an ancient mechanical calculator designed to calculate astronomical positions", which was found on an ancient shipwreck off the coast of the Greek island Antikythera in 1901. The Antikythera mechanism is dated to circa 150 BC and has been described as the world's oldest analogue computer.
Source: Wikimedia CCAS
The use of computing devices is not new to astronomy, but was transformed during the latter half of the twentieth century by the progressive accumulation of data from satellites and radio telescopes, opening new possibilities for non-optical observation and data capture, and creating new fields of research within stellar astronomy, many of which are far beyond the reach of amateur observation - although amateurs have continued to make surprising discoveries.
GNU/Linux, with its hobbyist traditions and Unix-like appearance, accessible code and scalability from mobile device to supercomputer, has been uniquely placed as an operating system for the specialist requirements of astronomers. Linux is used for the software that runs telescopes, the software that is used to pass instructions to satellites, and for the supercomputers and desktop utilities that enable astronomers to interpret their data.