Standards rule OK

My title comes from the chorus of a song on the Jam’s second album, This Is the Modern World (1977). Written by the band’s singer and guitarist Paul Weller, the song is a bombastically ironic attack on the enforcers of social conformity.

But if Weller were not a socially conscious rock musician and instead were a computational scientist, he might have still chanted, “Standards rule OK!” For without standards in hardware, software, and data formats, our work would be less efficient and less effective.

I first appreciated the importance of computer standards when I worked at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, in the early 1990s. My field, x-ray astronomy, was just three decades old at the time. The first pioneering missions could detect only a handful of bright objects. But their successors—among them the European Space Agency’s European X-ray Observatory Satellite (EXOSAT; 1983–86) and NASA’s Einstein Observatory (1978−82)—observed thousands of x-ray emitting stars, galaxies, and other cosmic objects. Then came Germany’s Röntgen Satellite (ROSAT; 1990−99) and Japan’s Ginga (1987−91), which added to that swelling collection.

Because spacecraft telemetry is limited by bandwidth, the data gathered and beamed to Earth by satellite observatories are packaged in efficient, instrument-specific formats—15 altogether for the instruments carried by the four spacecraft listed above. In contrast with the diversity of telemetry formats, the figures that embody the data’s scientific content (and ultimately appear in research papers) typically come in a smaller set of generic flavors: images, spectra, and light curves.

Creating those figures entails background subtraction, binning, filtering, and other generic tasks. In principle, the software that, say, Fourier-transforms a data stream from EXOSAT‘s Medium Energy instrument could do the same for a data stream from Ginga‘s Large-Area Counter. But the raw formats are as different as Dutch and Japanese. If the same software is to work with data from those and other missions, the data must be translated into a common format. And that format must be flexible enough to accommodate new instruments.

My former colleagues at GSFC duly picked such a format: flexible image transport system (FITS ). Originally developed for optical and radio data, FITS makes extensive use of headers and keywords. Like XML, FITS is extensible. Whenever a new detector technology comes online, new keywords and data structures are defined within the FITS framework. Granted, someone has to write an instrument-specific program that translates telemetry into FITS, but no one has to take on the more onerous job of rewriting data analysis software.

When I left GSFC in 1997, astronomers there and elsewhere used three software programs to analyze their data: Xspec (for spectra), Xronos (for light curves), and Ximage (for images). Now, 14 years later, they’re still using the same three programs for data from observatories that launched years after my departure.

FITS made its public debut in 1981 in a paper in Astronomy and Astrophysics. On 30 November of that same year, the Swedish pop group ABBA’s eighth and final album The Visitors became the first recording available on a new format, the compact disc. Although CD sales are waning, it remains a durable standard—at least I hope so. I have six Jam CDs.

This essay by Charles Day first appeared on page 96 of the September/October 2011 issue of Computing in Science & Engineering , a bimonthly magazine published jointly by the American Institute of Physics and IEEE Computer Society.