生命能否以气态形式存在？

脑洞大开的想法，我们见到的生命其形体大都包含固态的物质，有没有可能其他星球上的生命以气态或者液态形式存在，而且具有智慧

科幻小说中对于气态生命早已有各种各样丰富的想像了，不过如果要说科学家的看法，可以参考美国国家科学研究委员会编写的一本书《The Limits of Organic Life in Planetary Systems》，其中有一节就提到了气态生命：

6.3.1

Life in the Gas Phase
In the gas phase, chemistry is limited to
molecules that are sufficiently volatile under the ambient conditions to
deliver an adequate amount of material to the gas phase at moderate
temperatures. Raising the temperature does not necessarily solve the
problem. Although more molecules enter their gas phases as the
temperature is increased, organic molecules generally cease to be stable
at temperatures in excess of 500 K.
It is conceivable that in the vacuum of
interstellar space, life exists through molecules at high dilution
reacting in the gas phase. Grains have been suggested as a way of
collecting organic species, perhaps with an outer layer that protects
the inner layer from irradiation. The possible disadvantage of this, of
course, is the difficulty in holding together the components of the
interstellar life form. One advantage of such a life form would be that
it need not be encumbered by the lifetime of a planetary system. Indeed,
one can imagine that life in the gas phase might be associated with a
galaxy and its energy flux for nearly the age of the universe.