الزهرة والمشتري والمريخ على خط واحد في ظاهرة لن تتكرر حتى عام 2021
فرصة رائعة هذه الأيام، بدأت من يوم 24 من هذا الشهر
وتستمر حتى الثالث من نوفمبر/تشرين الثاني، حيث يشاهدون كوكب الزهرة
والمشتري والمريخ يعبرون مساراتهم في مشهد وظاهرة خلابة تسمى الثلاثي
الكوكبي، لن تتكرر حتى عام 2021.
ويكون كوكب الزهرة في البداية
على خط واحد مع المشتري والمريخ ومتقاربين بدرجة كبيرة، ثم يتعاقبون فيأتي
الزهرة بين المشتري والمريخ، ثم يبتعد المشتري ويكون الزهرة والمريخ على
مسافة قريبة بحيث يكادان يتلامسان للرائي. وأفضل وقت لمشاهدة هذه الظاهرة
الرائعة قبل الفجر.
ومن المعلوم أن الكواكب تدور
حول الشمس بسرعات مختلفة بناء على مدى قربها من الشمس، وكلما بعدت عنها
كانت حركتها أبطأ. ويستغرق الزهرة 22 يوما في دورانه مرة حول الشمس، في حين
أن المريخ يستغرق سنتين والمشتري 12 سنة.
ولهذا عندما ننظر إلى السماء من
الأرض يمكننا أحيانا أن نرى كوكبين يتجاوزان بعضهما كل في فلكه يسبح.
وتكمن روعة هذا الثلاثي الكوكبي في أن الناظر إليه لا يجد صعوبة في رؤيته
من أي مكان قبل الفجر حيث إن هذه الكواكب -وخاصة الزهرة والمشتري- تكون
مضيئة بشكل واضح.
وقد يتمكن الناظر من رؤية الكوكب الرابع عطارد فوق الأفق مع اقتراب الفجر.
المصدر : ديلي تلغراف
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27 Comments
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Venus, Jupiter and Mars cross paths in pre-Halloween spectacle for last time until 2021
The three planets, all pursuing their ordinary orbits around the sun, will be visible until around October 29 but will be best witnessed on October 26 before dawn
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Conjunction of Mars, Jupiter and Venus seen in Newcastle upon Tyne Photo: Demotix
10:55PM GMT 25 Oct 2015
27 Comments
Early risers are in for a treat this month, and for those rising early on October 26, the treat will be even greater.
Venus, Jupiter and Mars are crossing paths in an eerie pre-Halloween spectacle, also known as the planetary trio.
Forming a broad triangle in the eastern pre-dawn sky, the three planets
have grouped together as their separate journeys around the sun meet
for the last time until 2021, according to EarthSky.
The planetary trio, which is the name given to any three planets when
they group together inside a circle having a 5 degree diameter, will be
visible from now until from about October 24 until around October 29.
But according to EarthSky, the best time to witness the spectacle will be before dawn on October 26.
The plants in our solar system orbit the sun in a single flat plane and so when we look into the sky, we see a narrow edgeway of that plane.
The planets orbit the sun at different speeds, depending on how close they are to the sun.
The further away they are, the slower they go.
Venus only takes 225 days to orbit the sun once, whereas Mars takes two years and Jupiter takes 12.
Therefore, as we look into the sky from Earth, we can sometimes see two planets passing each other in their individual orbits.
And a planetary trio is even more special. Venus, Jupiter and Mars, all pursuing their ordinary orbits around the sun, have happened to pass near as other as viewed from Earth.
Venus and Jupiter rank as the third-brightest and fourth-brightest celestial bodies in all the heavens, respectively, after the sun and moon.
Therefore, star gazers should have little trouble viewing these two luminaries at morning dawn.
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But to view Mars, which is fainter, people might need to get up an hour or more before sunrise.
Mars is some 250 times fainter than Venus, the sky’s brightest planet, and some 25 times fainter than Jupiter, the sky’s second-brightest planet.
Some people may also be able to catch a glimpse of a fourth planet - Mercury - over the horizon as darkness gives way to dawn.
But according to EarthSky, the best time to witness the spectacle will be before dawn on October 26.
The plants in our solar system orbit the sun in a single flat plane and so when we look into the sky, we see a narrow edgeway of that plane.
The planets orbit the sun at different speeds, depending on how close they are to the sun.
The further away they are, the slower they go.
Venus only takes 225 days to orbit the sun once, whereas Mars takes two years and Jupiter takes 12.
Therefore, as we look into the sky from Earth, we can sometimes see two planets passing each other in their individual orbits.
And a planetary trio is even more special. Venus, Jupiter and Mars, all pursuing their ordinary orbits around the sun, have happened to pass near as other as viewed from Earth.
Venus and Jupiter rank as the third-brightest and fourth-brightest celestial bodies in all the heavens, respectively, after the sun and moon.
Therefore, star gazers should have little trouble viewing these two luminaries at morning dawn.
• Has Nasa's Kepler Telescope spotted signs of alien life?
But to view Mars, which is fainter, people might need to get up an hour or more before sunrise.
Mars is some 250 times fainter than Venus, the sky’s brightest planet, and some 25 times fainter than Jupiter, the sky’s second-brightest planet.
Some people may also be able to catch a glimpse of a fourth planet - Mercury - over the horizon as darkness gives way to dawn.
