Luokka Astronomiabulgariaenglantiespanjaesperantohollantiitaliajapanikreikkalatinalatvialiettuanorjaportugalipuolaranskaruotsisaksasuomitanskaturkkitšekkiunkarivenäjäviro

arclet arcminute arcsecond Arctic areography areology Arethusa Argo Argo Navis argument Ariel Aristaeus Arundhati ascensional Asclepius Asia asterism asteroid asteroid belt asteroseismic asterseismology Astraea astral astration astroarchaeology astrochemist astrochemistry astrogeology astrograph astroinformatics astrointerferometer astrometeorology astrometric astrometrized

astrometry astronomical unit astropause astrophoto astrophotography astrophotonic astrophotonics astrophysics astrosheath astrostatistics astrotail asymptotic giant branch Atalanta Atlas AU aureole Auriga Aurora AUs Ausonia autocollimation Autonoe axial tilt b backscatter balnicity barycentre baryogenesis baryonic dark matter Bayer designation Bayer system BBN Beatrix

Bebhionn Belinda Bellona belt Bergelmir Bestla BH Bianca Big Bang Big Crunch big crunch Big Dipper Big Rip binary binary star binary system binoculars BL Lac object black body black drop effect black dwarf black hole Black Turtle blackbody blitzar blood moon BLR blue blue dwarf blue flash blue moon blue starter blue straggler