Do you like pictures of outer space? Are you fascinated by the unbelievable beauty of some of the photographs of the universe? Then the Astronomy Calendar 2010 is probably a must have for you 
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Astronomy calendars are a wonderful way to get in touch with this field of science and can awaken the interest in space in kids and adults alike…
An Extrasolar planet also called Exoplanet is defined basically as a planet, outside our solar system, which revolves around a star (like our Sun). As of July 31, 2009 there are exactly 357 exoplanets listed in Extrasolar planet Encyclopedia.
How do we find EXOPLANETS?
There are many different methods used to find Extrasolar planets. Basically planets are very faint light sources as compared to their parent stars so finding such planets are extremely difficult and in addition to this the light from the parent star causes a glare that causes problems while detecting exoplanets. For this reason alone very few exoplanets have been found directly. The various indirect methods used to detect exoplanets are as follows:
ASTRONOMY: It consists of accurately measuring a star’s position in the sky and keeping a track of that particular position over a period of time to see how it behaves. Earlier handwritten records were kept but in the later 19th Century new photographic plates are used which improve the credibility and accuracy many times over. In this an exoplanet is found by searching for planets revolving around stars in a small circular and elliptical orbit.
• Radial Velocity: In this method similar to astronomy, the fact that a star with a planet revolving around it will move in its own small orbit in response to the planet’s gravity is of main importance. The next goal now is to detect and measure variations in the speed with which this star is moving toward or away from Earth [Radial Velocity]. This radial velocity can be determined from the displacements of the spectral lines because of Doppler Effect. This method is also called Doppler Spectroscopy and is more productive than astronomy.
• Pulsar Timing: Pulsars are small ultra dense neutron stars which emits radio waves. In this method these pulsars revolving, simultaneously radiating waves are recorded and these timings of radiations are observed and plotted to find any planets attached to it.
• Transit Method: when a planet crosses or transits in front of its parent star’s disc, then the observed visual brightness of the star decreases by a small amount. This amount by which the star dims slightly depends on the size of the star and on the size of the planet. The main drawback of this method is that it requires confirmation by radial velocity method.
• Gravitational Microlensing: This phenomenon occurs when the Earth, a lens star, a distant star are in perfect alignment. This occurs when the gravitational field of a star acts like a lens, magnifying the light coming from a distant background star. Such lensing events are short, lasting for days or weeks, as the two stars and Earth are all moving relative to each other. More than a thousand such events have been observed over the past ten years.
• Some other methods used prominently are Circumstellar discs, Eclipsing Binary, Orbital phase, Polarimetry etc. There are new scientific developments in the field of discovering Exoplanets.
Let us start from the beginning of this well known “Space Race”. This so called, analogy to arms race, was an informal competition between United States and Soviet Union to see who could outrun each other in advancements in space first. This race was set to explore outer space with artificial satellites and manned lunar missions. The leader in this race was Soviet Union launching Sputnik-I in 1957. Space technology became a major part in this conflict as it involved both potential military applications and the morale-boosting social benefits. During Cold War both nations gained great pride and superior technology and this competition forced Americans to show some superiority by planning to send “man to moon” and back to earth. This was achieved in 1969 under presidential term of J. F. Kennedy.
This was called Apollo 11, the fifth manned mission in the Apollo series to explore space, and became the first manned mission to set its foot on the Moon. After this mission, that had a big role in causing a chain reaction in spreading the presence of human kind throughout universe, there were several missions exploring space by different countries. But the end of lunar missions came in December 7, 1972, with the launch of Apollo 17 which involved three astronauts.
This mission used Lunar Rovers and surface excursions and many spacewalks. They returned from moon on December 19, 1972 through splashdown in the Pacific Ocean. This was the last mission to moon and Eugene Cernan is, to date, the last man ever to have walked on the Moon. While those involved in those space missions look back on their achievements that are embedded in both time and history, others are looking at the future for space exploration.
There were several different missions to other planets in the years following this lunar mission but man never returned to moon. The question that still arises is why? The answer as told by NASA and other space research organizations is that the expenditure on such missions was too high to afford, the space shuttle requires high maintenance and manned missions needed careful safety measures to keep the astronauts in space and the moon for a long time. Building on the best of Apollo and space shuttle technology, NASA’s 21st century space exploring system will be durable, affordable, versatile and safe but take some time to make.
This payload in the picture is the latest marvel of NASA which with the space shuttle can carry up to 6 crew members or astronauts into space or moon. NASA is also working very hard to make the new spacecraft operational by 2011, decreasing any gap in human space flight. The proposal called for the CEV [crew exploration vehicle] is to be ready by 2014, which will reflect the vision of returning to moon. There are other space research organizations of different countries trying to achieve the same and started on their specific lunar projects by end of 20th century for e.g. China is planning to send manned shuttle to moon by 2020. United States space research organization NASA is also currently designing ORION spacecraft which can carry 4-6 astronauts, launched by the ARES I, the launch vehicle. Both these space exploring components plan to send humans to moon again by end of year 2020. This project has been awarded to Lockheed Martin [LM] to develop, design, build and test the module. The first crewed Orion flight is to be tested in 2015.
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