glacier
probe
ancestor
extinct
global warming
melt
comet
pollution
climate
orbit
primate
a general increase in world temperatures caused by increased amounts of carbon dioxide around the Earth
to ask questions in order to find things out
the curved path through which objects in space move around a planet or star
a member of the most developed and intelligent group of mammals, including humans, monkeys, and apes
no longer existing
the general weather conditions usually found in a particular place
to turn from something solid into something soft or liquid
a member of your family who lived a long time ago
the process of making air, water, soil etc dangerously dirty and not suitable for people to use, or the state of being dangerously dirty
a large mass of ice that moves slowly
an object in space like a bright ball with a long tail, that moves around the Sun