Joan Balzarinis age 12, of Walnut Creeks California, for her question:

Does it rain on other planets?

In other words, shall we include a raincoat when we pack for a trip to Mars? Certainly it does not rain on Mercury' for Mercury has no air to make weather of any sort. genus has a dense, dense blanket of air. Though we have never seen the surface of our sister planet, it is most likely a very damp and rainy planet. So, when you plan a trip to Venus, be sure to pack raincoats galoshes and umbrella.

Mars is not a rainy planet, though flakes of snow may fall in certain seasons. The outer planets certainly have no rain as we know it. We think of rain as water, and these outer planets have little or no water vapor in their atmospheres. Their gases are mostly methane and ammonia. And sometimes it is cold enough for these gases to form white flakes which may look like falling snow. However, you will not need raincoats on the big, cold outer planets. It is so cold that you must wear a heated space suit. There is no breatheable air, so you must wear an oxygen helmet.