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WonderScience fact

The Sun holds about 99.86% of all the mass in the solar system. It is roughly 330,000 times as massive as the Earth and 109 times as wide, so the planets, moons, asteroids and comets together make up only about 0.14%.

Astronomy

Science

The story behind the card

The Sun formed about 4.6 billion years ago when a cloud of gas and dust collapsed under its own gravity. Most of the material fell to the centre and became the Sun; the rest flattened into a spinning disc in which the planets grew. That is why the Sun ended up with nearly everything. It is made mostly of hydrogen (about 73%) and helium (about 25%), and in its core hydrogen fuses into helium, releasing the energy that reaches us as sunlight. Of the small share left over, Jupiter and Saturn hold more than 90%. The four rocky planets, Earth included, together with all the dwarf planets, moons, asteroids and comets, make up less than 0.002% of the solar system's mass.

Türkçe oku
Güneş Sistemi'ndeki toplam kütlenin yaklaşık %99,86'sı Güneş'tedir. Güneş'in kütlesi Dünya'nınkinin yaklaşık 330.000 katı, çapı ise 109 katıdır; gezegenler, uydular, asteroitler ve kuyruklu yıldızların hepsi birden kütlenin ancak %0,14'ünü oluşturur.

Güneş yaklaşık 4,6 milyar yıl önce, dev bir gaz ve toz bulutunun kendi kütleçekimiyle çökmesiyle oluştu. Maddenin çoğu merkezde toplanıp Güneş'i oluşturdu; geri kalanı dönen bir diske yayıldı ve gezegenler bu diskte oluştu. Güneş'in kütlenin neredeyse tamamını toplamasının nedeni budur. Güneş büyük ölçüde hidrojenden (yaklaşık %73) ve helyumdan (yaklaşık %25) oluşur. Çekirdeğinde hidrojen çekirdekleri kaynaşarak helyuma dönüşür; açığa çıkan enerji bize güneş ışığı olarak ulaşır. Geriye kalan küçük payın %90'ından fazlası Jüpiter ile Satürn'dedir. Dünya dâhil dört kayalık gezegen, cüce gezegenler, uydular, asteroitler ve kuyruklu yıldızlar ise hep birlikte Güneş Sistemi kütlesinin %0,002'sinden azını oluşturur.

Sources and further reading

Background reading: Sun
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