For now, though, ###### they can do is ###### meteorites. These are pieces ###### Martian rock that landed ###### Earth after flying through ######.
Scientists can learn a ###### from meteorites. But often ###### don't agree on how ###### a rock is. This ###### make it hard to ###### what to think. And ###### certain space rocks, scientists ###### by as much as ###### billion years.
Mars itself ###### much older than 4 ###### years. So the question is: Do these rocks tell the beginning, or the end, of Mars' story?

"Young" Martian Rocks

Recently, a team ###### scientists tried to figure ###### how old one group ###### meteorites is.]]> Most Martian ###### rocks are very old. ###### shergottites are believed to ###### very young. Of course, ###### compared to other things ###### the solar system.
Most ###### believe shergottites were formed ###### volcanoes about 150 to ###### million years ago. That ###### during Earth's Jurassic period. ###### roamed our planet then.
###### they are right, then ###### had volcanoes not too ###### ago. And that might ###### made life on Mars ######, said scientist Munir Humayun.
###### some people believe that ###### are actually very old- ###### 4 billion years old.]]>