Recent evidence suggests that when the solar system formed 4.5 billion years ago, comets had liquid cores.

最近有证据指出，45亿年前太阳系形成的时候，彗星有液态的核。

youdao

Many scientists think our solar system formed from a giant, rotating cloud of gas and dust known as the solar nebula.

许多科学家认为太阳和太阳系的其他部分是由一团称为“太阳星云”的巨大的旋转着的气体和尘埃星云形成来的。

youdao

The Tagish meteor formed the same way all the asteroids and meteors in the solar system formed: accreting out of the primordial swirl of gas and dust that also gave rise to the sun and planets.

这块塔吉什湖的陨石与太阳系内其他陨石以及小行星形成过程完全相同，即：通过空间中的气体和尘埃涡旋积累形成（这同样是太阳和各个行星的形成过程）。

youdao

A month later a Lebanese power-sharing system was formed to divide power under religious lines.

VOA: standard.2009.09.24

The country formed a parliamentary system of government and elections were held.

VOA: standard.2009.08.27

It's by studying the dynamics of the icebergs in the rings that scientists hope to understand how the whole Solar System formed.

BBC: Saturn's beauty and power

Abell says these fragments may also provide planetary scientists with new windows onto details about how the solar system formed and how life evolved here on Earth.

FORBES: NASA Eager To Analyze Russian Meteor Fragments

So when we collect comet dust, we're actually collecting some stardust that was, you know, four and a half billion years old and was here when the solar system formed.

NPR: Stardust Set to Deliver Comet Samples