Geologists have recently determined that the minerals goethite and hematite exist in abundance on Mars, sure signs of the presence of water (see Figure 1 for a picture). None of those geologists have been to Mars, of course, but the unmanned rovers Spirit and Opportunity have. These rovers are equipped with three mass spectrometers, each of which is capable of determining the chemical composition of a solid with a high degree of accuracy. With such a precise chemical analysis in hand, geologists on Earth had no problem identifying the minerals.
A mineral is defined in part by a specific chemical composition. In theory, therefore, it is always easy to identify a mineral, if you can determine the chemical composition with a mass spectrometer like the Mars rovers. In reality, however, even if you are looking at rocks on Earth, determining the exact chemical composition of a substance involves significant time preparing the sample and sophisticated laboratory equipment (and often significant money). Luckily, it is usually unnecessary to go to such lengths, because there are much easier ways that require little more than a magnifying lens and a penknife.
They are both happening very slowly in a way
Quakes normally occur around one of the 3 plate tectonic movement
United States have over 500 million people living
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The relationship between the Aborigines and the Australian government has fluctuated throughout its history. During the British colonial period, Aborigines were persecuted with their land stolen and many of them killed. With little rights, the population dwindled and by the 1900s the natives were a small minority in their own land.
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