[原子]质量数

[原子]質量數Anumber羅馬紀年abUrbeCondia(AUC)艾伯耳星系團表Abellcatalog艾伯耳豐級(星系團)Abellrichnessclasses光行差；像差aberration光行差常數aberrationconstant光行差橢圓aberrationellipse光行差aberrationoflight光行差位移aberrationshift燒蝕(流星)ablation簡儀abridgedarmilla絕對年齡absoluteage絕對黑體absoluteblackbody絕對熱星等absolutebolometricmagnitude絕對亮度absolutebrightness絕對測定absolutedetermination絕對誤差absoluteerror絕對梯度absolutegradient真高度；絕對高度；絕對高程absoluteheight絕對星等absolutemagnitude絕對星等效應absolutemagnitudeeffect絕對視差absoluteparallax絕對攝動absoluteperturbation絕對光電星等absolutephotoelectricmagnitude絕對照相星等absolutephotographicmagnitude絕對光度學；絕對測光absolutephotometry絕對仿視星等absolutephotovisualmagnitude絕對自行absolutepropermotion絕對輻射星等absoluteradiometricmagnitude絕對空間absolutespace絕對分光光度梯度absolutespectrophotometricgradient絕對標準absolutestandard絕對溫度absolutetemperature絕對時間absolutetime絕對零點；絕對零度absolutezero吸收體；吸收器absorber吸收absorption吸收帶absorptionband吸收係數absorptioncoefficient吸收邊限absorptionedges吸收[譜]線absorptionline吸收[光]譜absorptionspectrum豐度；豐存度；豐盛度abundance豐度異常abundanceanomaly加速運動acceleratedmotion加速度acceleration重力加速度accelerationofgravity加速度計accelerometer偶然關聯accidentalconnection偶[然誤]差accidentalerror調節accommodation吸積；撞積accretion吸積盤accretiondisk累積accumulation準確度accuracy乙醛acetaldehyde(CH3CHO)乙氰acetonitrile(CH3CN)波江[座]α[星]；水委一Achernar(αEri)588號小行星；阿基里斯Achilles無[球]粒隕石achondrite消色[差]透鏡achromat消色[差]目鏡achromaticeyepiece消色[差]物鏡achromaticobjective消色差achromatism針狀星雲acicularnebula天蠍[座]β[星]；房宿四Acrab(βSco)南十字[座]α[星]；十字架二Acrux(αCrucis)輻射儀actinograph露光計；日射儀actinometer日射測量法；輻射測量actinometry作用[量]action活化；激活activation活化係數；激活係數activationcoefficient活躍星系核activegalacticnucleus(AGN)活躍星系activegalaxy活躍日珥；活動日珥activeprominence活躍日珥區；活動日珥區activeprominenceregion(APR)活躍區；活動區activeregion活躍太陽activesun活躍黑子日珥；活動黑子日珥activesunspotprominence真實頻率；實際頻率actualfrequency定朔actualsyzygymethod適應adaptation絕熱線adiabat絕熱塌縮adiabaticcollapse絕熱平衡adiabaticequilibrium絕熱起伏adiabaticfluctuation絕熱指數adiabaticindex(γ)絕熱過程adiabaticprocess絕熱脈動adiabaticpulsation絕熱溫度梯度adiabatictemperaturegradient鄰角adjacentangle鄰邊adjacentside調整螺絲adjustingscrew校正；調整adjustment2101號小行星；阿多尼斯Adonis緯度採用值adoptedlatitude經度採用值adoptedlongitude木衛十五Adrastea吸附作用adsorption吸附平衡adsorptionequilibrium吸附本領adsorptivepower近星點前移advanceofperiastron近日點前移advanceofperihelion十億年aeon天線aerial隕石；石質隕石aerolite超高大氣學；高層大氣物理學；大氣化學aeronomy隕鐵；鐵質隕石aerosiderite石隕鐵；石質鐵隕石aerosiderolite餘輝afterglow年齡特徵agecharacteristics月齡(月相)ageoftheMoon[空]氣冠(流星)aircap空氣射叢airshower氣輝airglow艾瑞盤Airydisk火星基準子午線Airy-0反照率albedo反照率計albedometer天鵝[座]β[星]；輦道增七Albireo(βCyg)大熊[座]ζ[星]；輔；開陽伴星Alcor(80UMa)金牛[座]η[星]；昴宿六Alcyone(ηTau)金牛[座]α[星]；畢宿五Aldebaran(αTau)仙王[座]α[星]；天鉤五Alderamin(αCep)亞耳芬速率Alfvenspeed阿耳芬波AlfvenWave飛馬[座]γ[星]；壁宿一Algenib(γPeg)英仙[座]β[星]；大陵五Algol(βPer)大陵[型]食雙星Algolsystem大陵[型]變星Algolvariable雙子[座]γ[星]；井宿三Alhena(γGem)假頻；假訊aliasing照準儀；游標盤alidade大熊[座]ε[星]；玉衡；北斗五Alioth(εUMa)阿顏德隕石Allendemeteorite容許誤差allowableerror仙女[座]γ[星]；天大將軍一Almach(γAnd)天文學大成(古書名)Almagest半人馬[座]ζ[星]；庫樓一Almair(ζCen)[天文]年曆；曆書almanac地平緯圈；等高圈almucantarα粒子；阿爾伐粒子alphaparticle(αparticle)長蛇[座]α[星]；星宿一Alphard(αHya)仙女[座]α[星]；壁宿二Alpheratz(αAnd)天鷹[座]α[星]；河鼓二；牽牛[星]；牛郎[星]Altair(αAql)經緯儀altazimuth地平[式]裝置altazimuthmounting地平緯度；高度altitude地平緯圈；高度圈altitudecircle鍍鋁aluminizing木衛五；阿摩笛亞Amalthea環境溫度ambienttemperature雙極性擴散ambipolardiffusion氨ammonia(NH3)氨邁射(微波)ammoniamaser磷酸二氫氨ammoniumdihydrogenphosphate(ADP)((NH4)H2PO4)1221號小行星；阿冥爾Amor安[培]ampere(A)超低鐵(LL)球粒隕石amphoterite放大器amplifier振幅；變幅amplitude振幅調度；調幅amplitudemodulation(AM)消像差望遠鏡anaberrationaltelescope河外星雲(古)anagalacticnebula類比；模擬analog分析器analyzer木衛十二；安那喀Ananke消像散透鏡anastigmat消像散性anastigmatism仙女[星]座Andromeda仙女座星系Andromedagalaxy(M31;NGC224)仙女座星雲AndromedaNebula仙女[座]流星雨Andromedids偏角angleofdeviation傾角angleofinclination折射角angleofrefraction視[線]角angleofsight垂線角angleofthevertical傾[斜]角angleoftilt埃(波長單位)(=10-8公分)angstrom(Å)角加速度angularacceleration角徑angulardiameter角色散angulardispersion角距[離]angulardistance角範圍；角展angularextent角視界angularfield角頻率angularfrequency角放大率angularmagnification角動量angularmomentum角程長度(流星)angularpathlength角分辨率angularresolution角半長徑angularsemi-majoraxis角半短徑angularsemi-minoraxis角距[離]angularseparation角大小angularsize角譜angularspectrum角速度angularvelocity非諧脈動anharmonicpulsation各向異性傳導率anisotropicconductivity各向異性介質anisotropicmedium各向異性散射anisotropicscattering各向異性宇宙anisotropicuniverse毀滅[作用]annihilation周年光行差annualaberration周年差(月球運動)annualequation周年視差annualparallax歲差；年進動annualprecession年自行annualpropermotion[周]年變[化]annualvariation[日]環食annulareclipse環狀星雲annularnebula亂年AnnusConfusionis近點月anomalisticmonth近點轉動；近點周anomalisticrevolution近點年anomalisticyear異常折射anomalousrefraction反常彗尾anomaloustail異常則曼效應anomalousZeemaneffect近點角；異常anomaly無名星系anonymousgalaxy斜長石anorthosite逆大陵變星[古]；天琴[座]RR[型]變星antalgol背點antapex南極圈antarcticcircle天蠍[座]α[星]；心宿二；大火Antares(αSco)天線antenna天線孔徑antennaaperture天線陣antennaarray天線[單]元antennaelement天線增益antennagain天線阻抗antennaimpedance天線匹配antennamatching天線方向圖平滑[化]antennapatternsmoothing天線功率方向圖antennapowerpattern天線溫度antennatemperature幻日anthelion消暈；反暈圈anti-halo反銀心anticenter反符合anticoincidence反物質antimatter反粒子antiparticle幻月antiselena逆向彗尾antitail奔離點antivertex唧筒[星]座AntliaA型特殊星Apstars