for those of you who happen to be new in this amazing and challenging area of astronomy, you will be lost looking for information to start your studies. there are too many books in astronomy on the market, but all of them turn out to be too easy or too complicated. they are designed for people that only want to be superficial in astronomy or astronomy students. but if you have a technical background or at least, feel good with some technical stuff, this compendium will fulfil all your expectacions. it covers everything about astronomy, from the basic in instrumentation until stars formation, planetary sciences and weird space objects. highly recommendable.