Archive for category Astronomy
How Astronomers Work
Astronomers are using telescopes or other observation instruments for observing the sky. Astronomers are using computers and telescopes to observe the universe. A few nights with a telescope watching often provide sufficient data to keep astronomers to spend months trying to analyze the data.
Until the 20th Century, all astronomers observe the visible light emitted by astronomical objects. Those astronomers are called the optical astronomers, because of watching the same part of the electromagnetic spectrum that the human’s eyes see. Astronomers are also using optical telescopes and imaging equipment to study the light from the objects. Today’s professional astronomers actually almost never look through a telescope. However, a telescope sends light from one object to a photographic plate or coupled to a computer-chip light-sensitive electronic device called a charge-device. Those devices are 50 times more sensitive than film, so now, astronomers can register one minutes of the image they had about one hour to record a movie.
Telescopes can use lenses to collect visible light, allows the direct observation and photographic records of distant objects. Those who wear glasses are called telescope, because they are using the properties of refraction or diffraction of light. The largest astronomical telescope in the 40-in telescope at Yerkes Observatory in Williams Bay, Wisconsin, that was founded in the 19 Century. Lenses are bending different colors of light by different amounts, the approach of such different colors slightly differently. The images of the major objectives can be produced are colored, often made to limit the comments on the filters. Filter, to limit the image for an order that the colored lenses of light to any image in the same contours and make the image more accurate than a picture that includes all colors that form the light. Also, because the light must pass through the spectacles, the lenses can be promoted only on the very edges.
Reflecting telescopes use mirrors that are easier to manufacture than telescopes and reflects all colors of light as well. All the largest telescopes today are the telescopes. The single largest telescopes of the Keck telescopes on an Observatory Center in Hawaii, Keck telescope mirrors are 394 (10.0 meters) in diameter. That Observatory Center is located at an altitude of 4205 m (13,796 feet), is particularly high. Air on the observatory is very clear, large projects, there are many telescopes.
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A Brief History of Space Travel From Sputnik 1 to Apollo 11
The History of Space Travel.
President Kennedy on September 12 1962 gave a speech in which he promised that we would build a rocket the size of a football field with various metal alloys many of which didn’t even exist yet. With the precision comparable to that of the finest watch which would launch a man to the moon, an unexplored celestial body which was 240,000 miles away traveling at over 25 thousand miles an hour carrying equipment which would be necessary for propulsion, guidance, control, communication, food, and survival, before the end of the decade (which was less than 8 years away).
Something like this sounded way to premature. Especially for a country that had less than a half an hour of manned space travel. But we were motivated both by our own need to explore the moon as well as the more realistic fact that the Russians had much more experience and were advancing alarmingly fast. We were at the height of the cold war and the fact that the Russians possessed greater space technology was an alarming fact in our national security.
But the actual starting gun happened in 1957 when the Russians released Sputnik then just 1 month later the put a dog in orbit as well. This was incredibly alarming to Americans since now the Russians were putting more than just satellites into space and there for could put nukes in space as well. Then the most damaging blow to American pride was in 1961 when the Russians had put a man in low orbit and he had done one circle around the earth in less than 2 hours.
America quickly picked up the pace in space exploration speeding the testing process too much which ended in several disastrously failed rocket tests. However were finally able to get into second place when we released a man called Alan Shepard into a brief sub orbit flight. At the time it was project mercury that was in control of manned space activity. 7 military test pilots were selected to become part of this project and in extension the newly formed NASA.
Upon our 6th mission we America were able to finally get in about 2 days of space travel of our own. Then after this came project Gemini the biggest difference between project mercury and project Gemini was in the fact that project Gemini did two manned space travels and there for were named after the latin word for twins. It acted as the connection between mercury and Apollo and had many members from both.
Gemini 4 had the first American EVA which was called extra vehicular activity or space walk (having a person outside of the spacecraft). We were catching up with Russia rapidly as they had done their first space walk a mere two and a half months before America. We continued to gather more and more momentum. Between 1965-1966 10 Gemini missions were able to get America even with Russia and we started breaking records of our own. The most well-known happening during Gemini 8 in which came the first docking between two space vehicles. Gemini 8 came incredibly close to complete disaster as the two spacecraft began spinning. They were spinning so fast that crew nearly blacked out separating made the spinning even worse. The two crew members were future Apollo members David Scott and the much more well-known Neil Armstrong as captain. Read the rest of this entry »