The Chandra X-Ray observatory should operate in space due to the nature of the radiation it is using. X-rays are high energy electromagnetic radiations. The observatory will not be able to function properly since it uses x-ray because, the rays cannot penetrate the earth's atmosphere. A radiation of this type would easily be cut off by the particles in the atmosphere. The observatory has to be positioned outside of the earth.
The period of Earth's history<span> that began 2.5 billion years ago and ended 542.0 million ... Stromatolites are </span>rare fossils<span> after about 450 million years ago</span>