Simple categories matching astronomical:

• catastrophe,
• structure,
• object,
• event,
• information,
• research,
• body,
• subject,
• hazard,
• quantity,
• equipment,
• project,
• time,
• instrument,
• phenomenon,
• apparatus,
• thing,
• occurrence,
• happening,
• symbol,
• data,
• matter,
• system,
• concept,
• cycle,
• patch,
• hardware,
• feature,

Members with property astronomical:

• star,
• lunar_eclipse,
• planet,
• planetary_observation,
• comet_transit,
• satellite,
• polarimeter,
• moon,
• solar_physics,
• shooting,
• solar_diameter,
• eclipse,
• use,
• galaxy,
• mount,
• midsummer_sunrise,
• comet,
• stellar_mass,
• star_turbulence,
• andromeda_nebula,
• supernova_hunting,
• sundial,
• venus_cycle,
• mass,
• twilight_data,
• nebula,
• venus_transit,
• sun,
• mars_opposition,
• x-ray_nova,
• stellar_core,
• nd,
• pulsar,
• twilight,
• planetary_conjunction,
• astrolabe,
• gnomon,
• planetary_motion,
• nearest_star,
• asteroid,
• occultation,
• solar_transit,
• sidereal_time,
• sunrise_time,
• stellar_atmosphere,
• sunset_data,
• solar_activity,
• sunrise,
• sunset,
• spectrometer,
• collision,
• gas_cloud,
• plane_crash,
• x-ray_burster,
• spectral_data,
• gamma-ray_burster,
• earth,
• astronomical_catalogue,
• remnant,
• relative_position,
• stellar_sign,
• quadrant,
• white_dwarf,
• cosmic-ray_study,
• transit,
• spacecraft,
• solar_eclipse,
• particular_position,
• red-giant_star,
• pulsar_wind,
• reflection_circle,
• meteor_storm,
• planet_ingress,
• equinox_sunrise,
• molecular_cloud,
• quasar,
• planetary_occultation,
• supernova,
• zodiacal_light,
• asteroid_impact,
• instrument,
• nearby_planet,
• big_bang,
• phase,
• sextant,
• planetary_system,
• period,
• meteor,
• active_galaxy,
• appearance,
• supernova_remnant,
• globular_cluster,
• set,
• planet_explosion,
• distant_galaxy,
• neb,
• northern_light,
• planetary_physics,
• culmination,
• opposition,
• supernova_explosion,
• heliacal_rising,
• asteroid_shower,
• suicide,
• accretion_disk,
• eclipse_cycle,
• moon_cycle,
• asteroid_passing,
• interior,
• planetary_location,
• giant,
• photometer,
• cometary_impact,
• x-ray_binary,
• nova,
• distant_star,
• passage,
• milky_way,
• transit_circle,
• gaseous_nebula,
• x-ray_burst,
• bright_star,
• interferometer,
• sandglass,
• gamma-ray_burst,
• midwinter_sunset,
• satellite_pass,
• new_supernova,
• solar_system,
• gas,
• dusk,
• explosion,
• solar_event,
• black_hole,
• natural_satellite,
• nearby_galaxy,
• planetary_nebula,
• dwarf_nova,
• planet_aspect,
• electromagnetic_storm,
• orbiting_body,
• earth_revolution,
• normal_star,
• double_meteor,
• conjunction,
• aurora,
• galactic_nucleus,
• emission_nebula,
• cycle,
• binary-star_coalescence,
• detection,
• continuing_expansion,
• solar_flare,
• pinhole_camera,
• star_system,
• individual_star,
• large_sundial,
• catastrophic_impact,
• jet,
• cluster,
• cosmic_radiation,
• lunar_occultation,
• asteroid_collision,
• emission,
• meteor_shower,
• position,
• dawn,
• interstellar_medium,
• bullet_cluster,
• binoculars,
• orion_nebula,
• gum_nebula,
• maximum_separation,
• dwarf_star,
• beautiful_comet,
• image,
• lunar_cycle,
• comet_landing,
• meteor_impact,
• interstellar_grain,
• constellation,