... particulate levels. Volcanoes spew out sulfur dioxide and large amounts of pulverized lava rock known as volcanic ash. A big volcanic eruption can darken the sky over a wide region and affect the earth's entire atmosphere. The 1991 eruption of Mount Pinatoubo in the Philippines, for example, dumped enough volcanic ash ... coal and was so severe that in 19th-century London, street lights were turned on by noon because soot and smog darkened the midday sky. Burning gasoline in motor vehicles is the main source of smog in most regions today. Powered by sunlight, oxides of nitrogen and vola...

• Word Count: 6167
• Approx Pages: 25
• Has Bibliography
• Grade Level: Undergraduate

... 102 new comets during the short course of its operation. In conclusion, the SOHO space project has given scientists around the world a better understanding of the brightest star in our sky. It has helped scientists unravel old mysteries and gave rise to new ones. Finally, this project will deepen our knowledge of the relationship between ourselves here on Earth and the ... ...

• Word Count: 709
• Approx Pages: 3
• Grade Level: Undergraduate

... , in the valley of Aialon!" And the sun stood still, and the moon stayed, while the nation took vengeance on its foe The sun halted in the middle of the sky; not for a whole day did it resume its swift course."* The way that the Church saw it, this Bible verse clearly affirmiated the sun's motion around the earth, in addition ... ...

• Word Count: 1974
• Approx Pages: 8
• Has Bibliography
• Grade Level: Undergraduate

... of its initial blast it was visible to the naked eye for about 18 months. In fact, the initial explosion probably appeared as one of the brightest stars in the sky. Today, astronomers are not studying visible light from the supernova, as Tycho would have seen it, but rather its X-ray light, which can be detected by both XMM-Newton and ... ...

• Word Count: 976
• Approx Pages: 4
• Grade Level: Undergraduate

... ordered that a special commission look at the manuscript and that commission recommended process by the Inquisition. The Inquisition served a paper to Galileo ordering him to appear in Rome the following October and although Galileo tried to prolong to encounter claiming ill health by Christmas the Inquisition ordered him again to come either voluntarily or in chains. Once there for months Galileo ... ...

• Word Count: 2318
• Approx Pages: 9
• Grade Level: Undergraduate