Nova - online puzzles

Online puzzle Nova

A nova (plural novae or novas) or classical nova (CN or plural CNe) is a transient astronomical event that causes the sudden appearance of a bright, apparently "new" star, that slowly fades over several weeks or many months. Novae involve an interaction between two stars that cause the flareup that is perceived as a new entity that is much brighter than the stars involved.

Causes of the dramatic appearance of a nova vary, depending on the circumstances of the two progenitor stars. All observed novae involve closely located binary stars (the progenitors), either a pair of red dwarfs in the process of merging, or a white dwarf and another star.

The main sub-classes of novae are classical novae, recurrent novae (RNe), and dwarf novae. They are all considered to be cataclysmic variable stars. Luminous red novae share the name and are also cataclysmic variables, but are a different type of event caused by a stellar merger. Also with similar names are the much more energetic supernovae (SNe) and kilonovae.

Classical nova eruptions are the most common type of nova. They are likely created in a close binary star system consisting of a white dwarf and either a main sequence, sub- giant, or red giant star.