The price of natural gas has virtually collapsed the last few years mainly due to massive new supply unlocked by new drilling techniques such as hydrofracking. Look at the chart of UNG, which attempts to track the price of natural gas.
Natural gas is a commodity, not a company so it is not going to disappear. At what point does one invest? When does the line stop going down? For short term investors of a year or less, picking a bottom now is probably too early. It is conceivable that it could drop another 20-30% first or might just stay down for a long time. I would love to see it flatten out for a few months or even years.
I am not a buyer yet, nor am I buyer of highly leveraged gas companies like CHK. But, if you have a long term horizon, say 5-10 years one could start buying here.