You don't need to; the Sun does a fine job of vaporizing the volatile chemicals in the nucleus of a comet.
coma
A cloud of gas surrounding the nucleus.
As comets approach the sun, they undergo several changes. The increase in temperature causes the icy nucleus of the comet to vaporize, creating a glowing coma around it. This coma is often accompanied by a tail pointing away from the sun due to the solar wind's effects on the released gas and dust. Additionally, the intense heat can cause the comet to fragment or even disintegrate completely.
Comets commonly develop two tails, a vapor trail, which we can see, and a gas/dust trail, which we may or may not be able to see. The tail develops when the heat of the sun causes the ices in the cometary nucleus to vaporize off. The tail always points directly away from the sun.
As a comet approaches the Sun, the heat causes ice and other volatile substances within the comet to vaporize. This forms a glowing coma (a cloud of gas and dust) around the solid nucleus of the comet. The solar wind then pushes this gas and dust away from the Sun, forming a tail that can stretch for millions of kilometers in the opposite direction of the Sun.
Offgassing occurs when comets, meteors, meteorites etc. are heated by an outside force (such as the sun or the atmosphere of a planet.)This heating causes the frozen gasses and particles of the object to vaporize, creating the clouds of gas and particles that surround comets and make them visible.
These are gas bubbles where water is starting to vaporize.
Comets!
Yes it does. After your car has been running, gas will vaporize. If the tank has more gas in it, there is less room for the gas to vaporize. This is also why its important to have your gas lid screwed on tightly to avoid gas to vaporize even more. If the gas cap it loose, you will lose gas due to the vaporization.
Comets.
a gas
It is a gas at room temperature!