Hello there I was wondering if it is possible to test rocks to see if they are from space? I ask because, this is true! Whilst I was gardening today a rock fell into my wheel barrow. It sounds crazy, but it did happen. The object is black, looks like coal, and is very light, I suppose like pumice. If It didn't fall from the sky, I would say it was a piece of normal earth rock, but as it came from above I'm very curious.
It can be quite difficult to distinguish meteorites from Earth rocks. If it is a couple of centimetres in size or larger and it were a meteorite then I would expect it to have left a dent in your wheelbarrow. A black exterior is typical since the outside of the rock would be heated to very high temperatures during it's descent, the exterior is often also pitted and can look obviously like it has been melted. It would not necessarily have been hot to the touch however since it's passage through the atmosphere is very rapid so the interior remains at the temperature of space (extremely cold), and the exterior will cool very quickly. The lightness would tend to suggest that it is not a meteorite, since meteorites are more often rather dense and heavy, but that isn't an absolute rule. If you want more information the Natural History Museum in London houses the national meteorite collection and have an identification service that may be able to help. If you do have a meteorite you are very lucky!