Flares are a space word. It begins with the letter f.
flying saucer
falling star
farrot
Some eight letter words starting with F and ending in E are:favoritefeminineflatlineflexibleforciblefracturefugitive
Some four letter words starting with S and ending with F are:selfserfsurf
Fast
Universe...
comet
There are a wide variety of space related words that begin with the letter f. Some of these include fireball, fissure, facula, and filament.
Finger
Farewell
6 letter f words ending with e:fiddlefacadefaminefeeblefoiblefelineficklefigurefinalefizzlefleecefondleforageforseefutilefreezefringefumble
fablefacetfaintfaithfakedfancyfangsfarcefalsefeastfeelsfencefieldfightfiftyfifthfinchfirstfilesfiendflaskflakeflackfluteflankflashfleckfleetfleshflintflingfloatflourfloodflockflungflushflunkfluidforgeforthforcefoamyfortyfoldsfoundfruitfrailframefrankfreedfreshfreakfrockfrostfrothfrozefurryfumes
frankincense
friendly and February