[March 15, 2001] The FITSML is an XML/XDF language rendition of the Flexible Image Transport System that is used primarily in astronomy. A pre-draft FITSML DTD is available, along with sample documents.
"The Flexible Image Transport System, or FITS, is the format adopted by the astronomical community for data interchange and archival storage. The FITS Support Office is responsible for documenting the FITS standard, participating in its evolution, and advising NASA astrophysics missions on how to present their data in FITS format.
"FITS (Flexible Image Transport System) is a data format designed to provide a means for convenient exchange of astronomical data between installations whose standard internal formats and hardware differ. A FITS data file is composed of a sequence of Header Data Units (HDUs). The header consists of keyword=value statements, which describe the organization of the data in the HDU and the format of the contents. It may provide additional information, for example, about instrument status or the history of the data. The data follow, structured as the header specifies. The data section of the HDU may contain a digital image, but, except for the first HDU, it doesn't have to. Other possible formats include tables and multidimensional matrices that are not images. An HDU need not contain data. If the first HDU contains data, they must be organized as an array of one or more dimensions; in subsequent HDUs, called extensions, other organizations are possible, consistent with certain rules. The 'Image' in FITS comes from the original use of the format to transport digital images, but it's not just for images any more."
References:
- IAU FITS Working Group
- FITS Support Office at the NASA Goddard Space Flight Center
- FITSML XML DTD. Version 0.04 for FITS HDUs [source]
- DTD tree view
- Example XML file, [cache]
- A Brief Introduction to the Flexible Image Transport System (FITS)
- "An XML Representation of FITS - Introducing FITSML." Presentation by B. Thomas, E. Shaya, J. Gass, J. Blackwell (Astronomical Data Center/GSFC-NASA, RITSS), C. Cheung (Astronomical Data Center/GSFC-NASA). January 11, 2001. "We describe a means by which FITS data may be encapsulated in XML using the eXtensible Data Format (XDF) - an XML based language for encapsulating n-dimensional scientific data. Our goal is to re-map (rather than to redefine) the FITS standards into an XML format. The advantages include: greater interoperability, parsing by XML aware browsers and applications, hierarchical structure for improved searchability, automatic validation, default values for header descriptions, extensibility for specialized usage and future development, and piggybacking on industry applications. We present our current work including a DTD and examples and discuss complexities, choices and future work."
- FITS archive at NRAO
- NOST (NASA/Science Office of Standards and Technology)
