ملف:SmallAsteroidImpacts-Frequency-Bolide-20141114-ar.jpg

SmallAsteroidImpacts-Frequency-Bolide-20141114-ar.jpg(800 × 560 بكسل حجم الملف: 236 كيلوبايت، نوع MIME: image/jpeg)

ملخص

الوصف
العربية: أحدث الشُهب والكويكبات الصَغيرة التي تتفكك في الغلاف الجَوي للأرض
English: New Map Shows Frequency of Small Asteroid Impacts, Provides Clues on Larger Asteroid Population

This diagram maps the data gathered from 1994-2013 on small asteroids impacting Earth's atmosphere

IMAGE: This diagram maps the data gathered from 1994-2013 on small asteroids impacting Earth's atmosphere to create very bright meteors, technically called "bolides" and commonly referred to as "fireballs". Sizes of red dots (daytime impacts) and blue dots (nighttime impacts) are proportional to the optical radiated energy of impacts measured in billions of Joules (GJ) of energy, and show the location of impacts from objects about 1 meter (3 feet) to almost 20 meters (60 feet) in size.

DESCRIPTION: A map released today by NASA's Near Earth Object (NEO) Program reveals that small asteroids frequently enter and disintegrate in the Earth's atmosphere with random distribution around the globe. Released to the scientific community, the map visualizes data gathered by U.S. government sensors from 1994 to 2013. The data indicate that Earth's atmosphere was impacted by small asteroids, resulting in a bolide (or fireball), on 556 separate occasions in a 20-year period. Almost all asteroids of this size disintegrate in the atmosphere and are usually harmless. The notable exception was the Chelyabinsk event which was the largest asteroid to hit Earth in this period. The new data could help scientists better refine estimates of the distribution of the sizes of NEOs including larger ones that could pose a danger to Earth.

Finding and characterizing hazardous asteroids to protect our home planet is a high priority for NASA. It is one of the reasons NASA has increased by a factor of 10 investments in asteroid detection, characterization and mitigation activities over the last five years. In addition, NASA has aggressively developed strategies and plans with its partners in the U.S. and abroad to detect, track and characterize NEOs. These activities also will help identify NEOs that might pose a risk of Earth impact, and further help inform developing options for planetary defense.

The public can help participate in the hunt for potentially hazardous Near Earth Objects through the Asteroid Grand Challenge, which aims to create a plan to find all asteroid threats to human populations and know what to do about them. NASA is also pursuing an Asteroid Redirect Mission (ARM) which will identify, redirect and send astronauts to explore an asteroid. Among its many exploration goals, the mission could demonstrate basic planetary defense techniques for asteroid deflection.
التاريخ
المصدر Derivative from this file
المؤلف
  • Original: NASA/Planetary Science
  • Derivative: علاء
إصدارات أخرى English
هذا رسمٌ مُعَدَّلٌ رقميَّاً من النسخة الأصليَّة. التعديلات هي: Translated to Arabic - عُرِبَت. يُمكن الاطلاع على النسخة الأصليَّة هنا: SmallAsteroidImpacts-Frequency-Bolide-20141114.jpg. المُستخدم الذي أجرى التعديلات هو: علاء.

ترخيص

Public domain يقع هذا العمل في النِّطاق العامّ في الولايات المُتحدة الأمريكيَّة لأَنَّه عملٌ خالِصٌ من إِنتاج وكالة الفضاء الأمريكيَّة. تنصُ حقوق التَّأليف والنَّشر الخاصَّة بوكالة الفضاء الأمريكيَّة على أنَّ "أعمال الوكالة غير مَحميَّة بحقوق التَّأليف والنَّشر ما لم يُذكر خلافُ ذلك". لمزيدٍ من المعلومات انظر القالِب {{PD-USGov}} وصفحة حقوق التَّأليف والنَّشر الخاصَّة بالوكالة وصفحة سياسة الصُّور الخاصَّة بمُختبر الدَّفع النَّفَّاث.
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