Atom to the positively charged nucleus by the attraction created from opposite electric charges. If an atom has more or fewer electrons than its atomic number, then it becomes respectively negatively or positively charged as a whole; a charged atom is called an ion. Electrons have been known since the late 19th century, mostly thanks to J.J. Thomson; see history of subatomic physics for details. Protons have a positive charge and a mass 1,836 times that of the electron, at . The number of protons in an atom is called its atomic number. Ernest Rutherford (1919) observed that nitrogen under alpha-particle
Battle of the Atom In January 2014, a mobile card game based on the event was released for Android devices. Battle of the Atom "Battle of the Atom" is a 10-part comic book crossover storyline published by Marvel Comics that debuted in September and October 2013 and ran through multiple X-Men books. The story involves the X-Men of the future traveling to present time in order to force the time-displaced X-Men to return to their rightful time, as their presence in the current timeline will result in disastrous consequences. "Battle of the Atom" was announced in April 2013. The story involves the X-Men of