sprites
... that sprites , large but very brief reddish forms of lightning that occur high over thunderstorms, were not photographed until 1989?
... that <b id="mwAfc"><a class="mw-redirect" href="./Sprites_(lightning)" id="mwAfg" rel="mw:WikiLink" title="Sprites (lightning)">sprites</a></b> <i id="mwAfk">(pictured)</i>, large but very brief reddish forms of <a href="./Lightning" id="mwAfo" rel="mw:WikiLink" title="Lightning">lightning</a> that occur high over <a href="./Thunderstorm" id="mwAfs" rel="mw:WikiLink" title="Thunderstorm">thunderstorms</a>, were not photographed until 1989?