Astronomers
use a special file format for storing and sending astronomical data
such as images and spectra. These are called Flexible Image Transport
System or FITS files for
short. This is the format of images you will get from the LCOGT archive.
FITS
files are more than just image files because at the start of every
FITS file is a header section, which contains important information
about the image, such as the number of pixels, the date the image was
taken, the telescope it was taken with, the exposure time, and much more.
What is DS9 and what does it do?
SAO/DS9 is a program that can be
used to view and manipulate FITS files. It can also save FITS files
as other more common image formats such as JPEG and TIFF. However,
none of these formats contain the same quality of information as the
FITS file. In particular, only 256 brightness levels are available
for each pixel in a JPEG, whereas FITS allows up to 65535.
DS9
is available for Windows, Mac and Linux. Download it from the SAO/DS9 website.
Instructions for Windows users and Mac users are available to help you through through the steps of downloading and starting DS9.
