a coma.
the bright cloud of gas that surrounds their nuclei as they approach the sun makes the surface difficult to determine.
Comets!
Comets.
Air is "gas" and that surrounds you.
comets are large balls of gas and ice that are flying round in space. :-)
An atmosphere.
smelly gas
gas
Comets.
A cloud of gas surrounding the nucleus.
The layer of gas that surrounds the Earth is called the atmosphere.
Frozen lumps of gas and rock in space are commonly referred to as comets. Comets are composed of ice, dust, gas, and rocky particles, often forming a visible tail as they approach the Sun and begin to vaporize.