- An A-type main-sequence star (AV) or A dwarf star is a main-sequence (hydrogen burning) star of spectral type A and luminosity class V (five). These stars have spectra defined by strong hydrogen Balmer absorption lines. They measure between 1.4 and 2.1 solar masses (M☉) and have surface temperatures between 7,600 and 10,000 K. Bright and nearby examples are Altair (A7), Sirius A (A1), and Vega (A0). A-type stars do not have convective zones and thus are not expected to harbor magnetic dynamos. As a consequence, because they do not have strong stellar winds, they lack a means to generate X-ray emissions.
- Space Invaders (Wikipedia)
Space Invaders is a 1978 shoot ’em up arcade video game developed and published by Taito. It was released in Japan in April 1978, with the game being released by Midway Manufacturing overseas. Commonly considered to be one of the most influential video games of all time, Space Invaders was the first fixed shooter and the first video game with endless gameplay (meaning there was no final level or endscreen) and set the template for the genre. The goal is to defeat wave after wave of descending aliens with a horizontally moving laser cannon to earn as many points as possible.