Similar to 宇都宮・ジョーンズ彗星
 - (845854) 2018 LF16(845854) 2018 LF16
 - AAVSO (小惑星)8900 AAVSO
 - Abell 2029Abell 2029
 - Abell 262Abell 262
 - ACE (探査機)Advanced Composition Explorer
 - ACRIMSATACRIMSAT
 - ADS 16402ADS 16402
 - ADS 7251ADS 7251
 - AGILEAGILE (satellite)
 - AG星表Astronomische Gesellschaft Katalog▲1 trends
 - AMOS (小惑星)8721 AMOS
 - Am星Am star
 - ANSAstronomical Netherlands Satellite
 - ANS (小惑星)9996 ANS
 - ANTARESANTARES (telescope)
- Ap/Bp星Ap and Bp stars
 - APL (小惑星)132524 APL
 - APM 08279+5255APM 08279+5255
 - ARIEL (宇宙望遠鏡)ARIEL
- Arp 220Arp 220
 - Arp 273Arp 273
 - ASTE望遠鏡Atacama Submillimeter Telescope Experiment
 - ASTRO-GAstro-G
 - AT2018cowSN 2018cow
 - AURIGAAURIGA
 - A型主系列星A-type main-sequence star
 - A型小惑星A-type asteroid
 - B2FH論文B2FH paper