Open FITS File

The Flexible Image Transport System (FITS) is a digital file format used mainly by scientists working in the field of astronomy. FITS files are designed to store scientific data and related metadata with high precision, making them an essential tool for researchers. In this article, we will discuss the possible formats of FITS files and ways to open and use them.

Understanding FITS File Structure

FITS files can be divided into two main categories: primary and extension. The primary FITS file contains a main data array, whereas the extension FITS files have various types of data arrays like images, tables, or metadata. These files are organized into a series of Header/Data Units (HDUs), which carry metadata in the form of a collection of key-value pairs in the header and the data in the data array. The header and data units facilitate easy reading and processing of the FITS files. For more information about FITS files, visit the FITS primer prepared by NASA's Goddard Space Flight Center.

Image Formats in FITS Files

There are different types of image formats used in FITS files. The primary image format is a two-dimensional array of integers or floating-point values. Extensions to the FITS standard support three-dimensional images, such as spectral data cubes or time-series data with multiple image planes. For more information on various image formats supported by the FITS standard, refer to the FITS standard document.

Opening and Viewing FITS Files

There are several tools available to open and view FITS files. Some popular ones are:

• DS9 (SAOImage) - A popular and versatile astronomical imaging and data visualization tool. Available for Windows, macOS, and various UNIX platforms.
• Aladin - A well-known interactive sky atlas that allows users to visualize, manipulate, and analyze astronomical data stored in FITS files. Available for Windows, macOS, and Linux.
• TOPCAT - A Java-based application designed for working with tabular data in FITS and other file formats. Available for Windows, macOS, and Linux.

Working with FITS Files

For researchers and developers who need to work with FITS files, there are several programming libraries available that provide dedicated support for reading, writing, and manipulating FITS data. Some popular programming languages and their corresponding libraries include:

• Python: Astropy - A community-developed library for astronomy that includes the astropy.io.fits module dedicated to handling FITS files.
• Java: nom-tam-fits - A well-documented library providing an API for reading, writing, and manipulating FITS files in Java.
• C: CFITSIO - A widely-used library for reading, writing, and modifying FITS files, provided by NASA's Goddard Space Flight Center.
• R: FITSio - A package for reading and writing FITS files in the R programming language.

FITS File Important Information

FITS files are vital to the scientific community, particularly astronomers, astrophysicists, and others working with astronomical data. Understanding their structure, formats, and various tools available for opening, viewing, and working with FITS files is critical for those interested in utilizing them for research. The links provided throughout this article offer detailed information about the different aspects of FITS files and guidance on how to effectively use them.