Astronomy Day နကၡတၲေဗဒေန႔

၂ဝ၁၆ ခုႏွစ္ ေမလ ၁၃-၁၄ ရက္ဟာ နကၡတၲေဗဒေန႔ျဖစ္ပါတယ္။ အေမရိကန္ ျပည္ေထာင္စုမွာ ၁၉၇၃ ကတည္းကစျပီး ေန႔တေန႔အျဖစ္ သတ္မွတ္ခဲ့ပါတယ္။ ေန႔သတ္မွတ္တာမွာ လရဲ႕ျဖစ္စဥ္နဲ႔ ဆက္ထားတယ္။
2015 April 25-April 25, September 19-September 21
2016 May 14-May 13, October 8-October 9
2017 April 29-May 2, September 30-September 27

နကၡတၲေဗဒဆိုတာ ၾကယ္ေတြ၊ ဂယ္လက္ဆီေတြ၊ ျဂိဳလ္ေတြ၊ လေတြ၊ ဥကၠာခဲေတြ၊ ေကားမက္ေတြ၊ နီျဗဴးလပ္ေတြကို ေလ့လာတဲ့ သဘာဝသိပၸံပညာရပ္တခုျဖစ္တယ္။ ျဖစ္စဥ္ၾကီးေတြလည္းေလ့တာတယ္။ ဥပမာ Supernovae explosions ဆူပါႏိုဗာေပါက္ကြဲမႈၾကီး၊ Gamma ray bursts ဂါမာေရာင္ျခည္ေပါက္ကြဲမႈၾကီးေတြျဖစ္တယ္။ ေရွးကတည္းက ေလ့လာခဲ့တာပါ။ ေဘဘီလံုေခတ္၊ ဂရိေခတ္၊ အိႏၵိယ၊ အီဂ်စ္၊ တရုပ္၊ မာယာေခတ္ေတြကတည္းက ျဖစ္ပါတယ္။ ၂ဝ ရာစုမွာ တိုးတက္လာတယ္။ အာကာသထဲမွာရွိေနၾကတဲ့အရာေတြ တည္ေနရာကို တိုင္းတာႏိုင္လာတယ္။ ဂယ္လီလီယို၊ ေကာ့ပါးနီးကပ္စ္၊ နယူတန္တို႔က အလြန္ထင္ရွားသူေတြျဖစ္တယ္။

Cosmology စၾက္ာဝဠာေဗဒအရ ကြ်န္ေတာ္တို႔ေနထိုင္ရာစၾက္ာဝဠာၾကီးဟာ ႏွစ္ေပါင္း ၁၃႕၈ ဘီလီယန္ သက္တမ္း ၾကာေနျပီလို႔သိလာရတယ္။ Big bang ၾကီးျဖစ္ခဲ့တယ္လို႔ ၁၉၆၅ မွာ ယူဆခ်က္ထြက္လာတယ္။ ျဂိဳလ္ၾကီး (၉) လံုးလို႔ မွတ္သားခဲ့ရာကေန အခုေတာ့ (၈) လံုးသာလက္ခံေတာ့တယ္။ Mercury မာက်ဴရီ (ဗုဒၶဟူးျဂိဳလ္)၊ Venus ဗီးနပ္စ္ (ေသာၾကာျဂိဳလ္)၊ Earth အာ့သ္ (မာၻေျမျဂိုလ္)၊ Mars မားစ္ (အဂၤါျဂိဳလ္)၊ Jupiter ဂ်ူပီတာ (ၾကာသပေတးျဂိဳလ္)၊ Saturn ေစတန္ (စေနျဂိဳလ္)၊ Uranus ယူေရးနပ္စ္နဲ႔ Neptune နက္ပ္က်ဴးျဂိဳလ္။ Pluto ပလူတို မပါေတာ့ပါ။

Sun ေန
သက္တမ္း ၄႕၆ ဘီလီယန္ႏွစ္ရွိျပီး၊ ကမာၻနဲ႔ မိုင္ေပါင္း 149.60 million km (92.96 million mi) ေဝးတယ္။ ေနမ်က္ႏွာျပင္ေပၚမွာ အပူခ်ိန္ ၅၅ဝဝ ဒီဂရီ (ဆဲလ္စီယပ္စ္) သို႔ ၁ဝဝဝဝ ဖါရင္ဟိုက္ပူတယ္။
Equatorial Radius = 695,508 km (432,168.6 miles)
Equatorial Circumference = 4,370,005.6 km (2,715,395.6 miles)
Volume = 1,409,272,569,059,860,000 km3 (338,102,469,632,763,000 miles3)
Mass = 1,989,100,000,000,000,000,000,000,000,000 kg (4,385,214,857,119,400,000,000,000,000,000 lbs)
Density = 1.409 g/cm3
Surface Area = 6,078,747,774,547 km2 (2,347,017,636,988 square miles)
Surface Gravity = 274.0 m/s2 (899.0 ft/s2)
Escape Velocity = 2,223,720 km/h (1,381,756 mph)
Sidereal Rotation Period = 25.38 Earth Days 609.12 Hours
Synodic Period: 27.2753 days
Rotation Period at Equator: 26.8 days
Rotation Period at Poles: 36 days
Velocity Relative to Near Stars: 19.7 km/s
Solar Constant: 1.365 - 1.369 kW/m2

Mars: Planet Profile မားစ္ (အဂၤါျဂိဳလ္)
Mass (kg) 6.42 x 1023
Diameter (km) 6787
Mean density (kg/m3) 3940
Escape velocity (m/s) 5000
Average distance from Sun 1.524 AU (227,936,640 km)
Rotation period (length of day in Earth days) 1.026
Revolution period (length of year in Earth days)     686.98
Obliquity (tilt of axis degrees) 25
Orbit inclination (degrees) 1.85
Orbit eccentricity (deviation from circular) 0.093
Maximum surface temperature (K) 310
Minimum surface temperature (K) 150
Visual geometric albedo (reflectivity) 0.15
Atmospheric components 95% carbon dioxide, 3% nitrogen, 1.6% argon

Jupiter: Planet Profile ဂ်ူပီတာ (ၾကာသပေတးျဂိဳလ္)
Mass (kg) 1.90 x 1027
Diameter (km) 142,800
Mean density (kg/m3) 1314
Escape velocity (m/s) 59500
Average distance from Sun 5.203 AU (778,412,020 km)
Rotation period (length of day in Earth days) 0.41 (9.8 Earth hours)
Revolution period (length of year in Earth years) 11.86
Obliquity (tilt of axis degrees) 3.08
Orbit inclination (degrees) 1.3
Orbit eccentricity (deviation from circular) 0.048
Mean surface temperature (K) 120 (cloud tops)
Visual geometric albedo (reflectivity) 0.44
Atmospheric components 90% hydrogen, 10% helium, .07% methane

Mercury: Planet Profile မာက်ဴရီ (ဗုဒၶဟူးျဂိဳလ္)
Mass (kg) 3.3 x 1023
Diameter (km) 4879.4
Mean density (kg/m3) 5420
Escape velocity (m/s) 4300
Average distance from Sun 0.387 AU (57,909,175 km)
Rotation period (length of day in Earth days) 58.65
Revolution period (length of year in Earth days)     87.97
Orbit inclination (degrees) 7
Orbit eccentricity (deviation from circular) 0.206
Mean surface temperature (K) 452
Maximum surface temperature (K) 700
Minimum surface temperature (K) 100
Visual geometric albedo (reflectivity) 0.12
Largest known surface feature Caloris Basin (1350 km diameter)
Atmospheric components trace amounts of hydrogen and helium
Surface materials basaltic and anorthositic rocks and regolith

Venus: Planet Profile ဗီးနပ္စ္ (ေသာၾကာျဂိဳလ္)
Mass (kg) 4.87 x 1024
Diameter (km) 12104
Mean density (kg/m3) 5250
Escape velocity (m/s) 10400
Average distance from Sun 0.723 AU (108,208,930 km)
Rotation period (length of day in Earth days) 243.02 (retrograde)
Revolution period (length of year in Earth days)     224.7
Obliquity (tilt of axis degrees) 178
Orbit inclination (degrees) 3.39
Orbit eccentricity (deviation from circular) 0.007
Mean surface temperature (K) 726
Visual geometric albedo (reflectivity) 0.59
Highest point on surface Maxwell Montes
(17 km above mean planetary radius)
Atmospheric components 96% carbon dioxide, 3% nitrogen, 0.1% water vapor

Saturn: Planet Profile ေစတန္ (စေနျဂိဳလ္)
Mass (kg) 5.69 x 1026
Diameter (km) 120660
Mean density (kg/m3) 690
Escape velocity (m/s) 35600
Average distance from Sun 9.537 AU (1,426,725,400 km)
Rotation period (length of day in Earth days) 0.44 (10.2 Earth hours)
Revolution period (length of year in Earth years) 29.46
Obliquity (tilt of axis degrees) 26.7
Orbit inclination (degrees) 2.49
Orbit eccentricity (deviation from circular) 0.056
Mean temperature (K) 88 K (1 bar level)
Visual geometric albedo (reflectivity) 0.46
Atmospheric components 97% hydrogen, 3% helium, .05% methane

Uranus: Planet Profile ယူေရးနပ္စ္ျဂိဳလ္
Mass (kg) 8.68 x 1025
Diameter (km) 51118
Mean density (kg/m3) 1290
Escape velocity (m/s) 21300
Average distance from Sun 19.19 AU (2,870,972,200 km)
Rotation period (length of day in Earth days) 0.72 (17.9 Earth hours)(retrograde)
Revolution period (length of year in Earth days) 30,685 (84 Earth years)
Obliquity (tilt of axis degrees) 97.9
Orbit inclination (degrees) 0.77
Orbit eccentricity (deviation from circular) 0.047
Mean temperature (K) 59
Visual geometric albedo (reflectivity) 0.56
Atmospheric components 83% hydrogen, 15% helium, 2% methane (at depth)

Neptune: Planet Profile နပ္က်ဴးျဂိဳလ္
Mass (kg) 1.02 x 1026
Diameter (km) 49528
Mean density (kg/m3) 1640
Escape velocity (m/s) 23300
Average distance from Sun 30.07 AU (4,498,252,900 km)
Rotation period (length of day in Earth days) 0.67 (19.1 hours)
Revolution period (length of year in Earth days) 60,190 (164.8 Earth years)
Obliquity (tilt of axis degrees) 29.6
Orbit inclination (degrees) 1.77
Orbit eccentricity (deviation from circular) 0.009
Mean temperature (K) 48
Visual geometric albedo (reflectivity) 0.51
Atmospheric components 74% hydrogen, 25% helium, 1% methane (at depth)

Pluto: Planet Profile ပလူတိုျဂိဳလ္
Mass (kg) 1.29 x 1022
Diameter (km) 2300
Mean density (kg/m3) 2030
Escape velocity (m/s) 1100
Average distance from Sun 39.48 AU (5,906,376,200 km)
Rotation period (length of day in Earth days) 6.39 (retrograde)
Revolution period (length of year in Earth years)     247.92
Obliquity (tilt of axis degrees) 122.5
Orbit inclination (degrees) 17.15
Orbit eccentricity (deviation from circular) 0.248
Mean temperature (K) 37
Visual geometric albedo (reflectivity) about 0.5
Atmospheric components perhaps methane and nitrogen
Surface materials perhaps methane ice

စၾက္ာဝဠာၾကီးဟာ အခ်င္းဝက္မ်ဥ္း ၁၃႕၇ ဘီလီယန္ အလင္းႏွစ္ရွိတယ္။ အလင္းႏွစ္ ၁၅၆ ဘီလီယန္ က်ယ္ဝန္းတယ္။ အလင္းႏွစ္ ၁ ႏွစ္ဆိုတာ 9.4607 × 1012 km ရွိတယ္။ တနည္းအားျဖင့္ ၆ ထရီလီယန္မိုင္ရွိတယ္။ စၾက္ာဝဠာၾကီးထဲမွာ ၾကယ္ေပါင္း ၁ဝဝ ဘီလီယန္ရွိမယ္။

ကမာၻျဂိဳလ္ဟာ ထုထည္ 5.98 x 1024 kg ရွိတယ္။ အခ်င္းမ်ဥ္း 12756 km ရွိတယ္။ ပ်မ္းမွ်သိပ္သီးဆ 5520 kg/m3 ရွိတယ္။ ေနကေန ပ်မ္းမွ် 149,597,890 km ကြာေဝးတယ္။ လည္ေနတာ တပတ္ျပည့္ဘို႔ 23.93 hours နာရီၾကတယ္။ ေနကိုတပတ္ျပည့္ဘို႔ 365.26 ရက္ၾကာတယ္။ 23.4 ဒီဂရီေစာင္းေနတယ္။ ဝန္းက်င္မွာ 78% nitrogen, 21% oxygen, 1% argon ဓါတ္ေငြ႔ေတြရွိေနၾကတယ္။

ကမာၻကိုပတ္ေနတဲ့ လဟာ အခ်င္းမ်ဥ္း 3,475 km ရွိတယ္။ ပတ္လမ္းအကြာအေဝး 384,400 km ရွိတယ္။ ၂၇႕၃ ရက္မွာ တပတ္ျပည့္တယ္။ လမ်က္ႏွာျပင္မွာ အပူခ်ိန္ (-233 to 123 °C) ရွိတယ္။

အတၲ၊ မာန္မာန၊ ေဒါသေတြအျပည့္နဲ႔လူသားတေယာက္ဟာ စၾက္ာဝဠာၾကီးထဲမွာ အမံႈေလးတခုစာမွ်မၾကီးမားပါတကား။

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