As well as being very hot, the ionised gas of the corona (called plasma) has a superthin consistency. It is less than a billionth of the density of the hydrogen that makes up the main ball of the Sun.

日冕的电离气体（又叫等离子体）不仅非常炙热，而且异常稀薄，其密度还不到组成太阳主体的氢气密度的十亿分之一。

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Dr Ardavan's theory describes how the gyrating star generates an intense magnetic field, which polarises the ionised gas or plasma surrounding it.

ECONOMIST: Physics

For instance, the ultra-thin layers of graphene (a two-dimensional form of graphite) are formed by injecting liquid solutions containing carbon and silicon into an extremely hot, ionised gas (plasma) of argon.

ECONOMIST: MONITOR