numerical expressions,

quantities and tables

for astrophysics

These pages are an electronic version of a notebook I started years ago, basically when I embarked on my PhD. Having little memory for formulae and numerical values of constants, I decided to copy them in a notebook that would follow me wherever I worked. This book has grown old and now it's a bit too old to carry around. Therefore I am gradually transferring it to a numerical support. This way I can consult it everywhere there is a computer (and there usually is a computer close to where I work) and you can use it too...

There is a vague order but since formulae were accumulated with time, there is no completeness. Here are the contents:

I try to include most of the information inside these pages but some already exists and should not be duplicated so I include here a table of links providing related informations
Arp catalog   Astro Calculators   Precession tool   Elementary astronomy

Although most of these formulae and values where gathered from many sources, there are a few books that I have used widely and that therefore deserve credit:

If you find an error in these pages, please email me at

I developped this site with a variety of tools and techniques. I also have to include some legal acknowledgements and informations. All is included here.

Last modification: 6/12/2000 in the IRAS pages