The impact factor or journal impact factor of a tutorial journal may be a scientometric index that reflects the yearly average number of citations that articles published within the last two years during a given journal received. it's frequently used as a proxy for the relative importance of a journal within its field; journals with higher impact factors are often deemed to be more important than those with lower ones.
Astrophysics is that the branch of astronomy that employs the principles of physics and chemistry "to ascertain the character of the astronomical objects, instead of their positions or motions in space". Among the objects studied are the Sun, other stars, galaxies, extrasolar planets, the interstellar space, and therefore the cosmic microwave background. Emissions from these objects are examined across all parts of the spectrum, and therefore the properties examined include luminosity, density, temperature, and chemical composition. Because astrophysics may be a very broad subject, astrophysicists apply concepts and methods from many disciplines of physics, including Newtonian mechanics, electromagnetism, physics, thermodynamics, quantum physics, relativity, nuclear and high-energy physics, and atomic and molecular physics.
Astronomy & Astrophysics is a peer-reviewed scientific journal covering theoretical, observational, and instrumental astronomy and astrophysics. It is one of the premier journals for astronomy in the world. The journal is published by EDP Sciences every month. Since 2011 the editor-in-chief is Thierry Forveille.