April 2011 | Blogs
Wednesday, April 13, 2011
Where in the Solar System is Ceres?
My daughter came home from school today and wanted to know where Ceres is located. She and her classmate disagreed, she thought Ceres was in the asteroid belt and he thought it was in the outer reaches of the Solar System near Pluto. My daughter was right; it is in the asteroid belt. Ceres is one of five dwarf planets in the Solar System. It is the closest dwarf planet to Earth. The other four dwarf planets are Pluto (the most famous), Eris, Makemake, and Haumea. These four are technically considered to be plutoids because they orbit the sun beyond Neptune. Ceres was discovered in 1801 by Giuseppe Piazzi, a monk in Sicily, Italy. He...
Sunday, April 10, 2011
How Old is the Earth?
My daughter recently asked me, “How old is the Earth?” I thought for bit and guessed 2 billion years old. My rationale was that dinosaurs first roamed the Earth about 200 million years ago, so 2 billion years seemed sufficiently long. I was wrong. Scientists estimate that the Earth is about 4.5 billion years old. To determine the age of the Earth, scientists study rocks and use a process called radiometric dating to determine the age of the rocks. Geologists have discovered rocks that are at least 3.5 billion years old on each of Earth’s continents. In north central Canada, scientists discovered a rock formation...
Friday, April 8, 2011
Can a Star Be Reborn?
Yes! Astronomers from the Harvard-Smithsonian Center for Astrophysics have identified two dying stars that will come together to form a new star. The two dying stars are white dwarfs. A white dwarf is a star at the end of its life. It is very dense and hot. The astronomers have found two white dwarfs that are quickly spinning around each other every 39 minutes at a rate of 270 miles per second (1 million miles per hour)! The two stars are very close together, and in fact, they are closer than the Earth and the Moon to each other. Since the two stars are spinning around each other so closely and quickly, they are creating gravitational waves...