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Our Sun's Twin
The Hubble Space Telescope
The Hubble Space Telescope is a wonder of engineering and ingenuity. The idea for building a telescope in space that could see far beyond our own solar system was conceived in 1962 by the National Academy of Sciences in the United States. It wasn't until 1977 that the Congress of the United States finally voted to actually fund the project.
The Hubble telescope is named for Edwin P. Hubble. Hubble was a trailblazing astronomer who was born in 1889 and died in 1953.
The Hubble telescope has given astronomers unprecedented access to views of deep space. It has actually revolutionized the science of astronomy in many ways. The Hubble Telescope can "see" far beyond our own solar system and beyond our own galaxy into deep space, where fledgling galaxies are only just beginning to form.
The Hubble telescope wasn't launched until 1990 even though it was originally scheduled to launch in 1983. The launch experienced many delays, the most notable of which was the space shuttle Challenger disaster in 1986. The Hubble telescope was launched into space on April 25, 1990, and was sending pictures back to earth in a matter of days -- but the pictures were out of focus. The problem was found to be a flaw in the giant mirror -- it was too flat on one edge by 1/50th the width of a single human hair.
In 1993, the problem with the Hubble was resolved when the space shuttle Endeavor captured the Hubble Space Telescope and added a camera to correct problems with the telescope's primary mirror.
There have been other problems with the Hubble over the years, but it is still one of the wonders of the world and is providing astronomers with information that they could never have gained access to without it.
See Also:
Mirrors & Lenses
The Planet Neptune
The Stars
Our sun is a star. It is one of the billions of stars in the Milky Way Galaxy. On a clear night, when you look up at the sky, you can see thousands of stars with your naked eye. If you have a pair of binoculars or a telescope, you can see more stars than you could ever hope to count.
Each star is unique, but they all share things in common as well. Stars are born from interstellar gas clouds, nuclear fusion causes them to shine and stars die. Sometimes the death of a star is a very dramatic event.
Cold interstellar clouds or nebula, like the Orion Nebula and the Eagle Nebula, are the incubators and nurseries from which stars are born. An extremely simplified description is that gravitational collapse happens and forms a rotating gas globule. The resulting globule spins faster and faster. The central core becomes a star while the other material becomes planets or asteroids.
The life of a star begins and ends with a battle between two forces: gravity and pressure. It takes energy for a star to live, and this energy comes almost entirely from nuclear fusion of lighter elements into heavier elements. This is the energy through which a star can shine for millions or billions of years.
Stars fuse hydrogen to helium for most of their lifetime. This is referred to as the "main sequence" of a star's life. Our sun, Vega, Sirius, and Spica are all stars that are in their main sequence. Once the hydrogen in the core of a star has been used up, the star becomes a red giant like Betelguese, Arcturus, Aldebaran and Antares.
A star's life is limited because the hydrogen at the core is not self-replenishing and will eventually be used up. A star cannot depend upon thermal energy to resist the pull of gravity forever, and a star's final fate depends on whether something other than thermal pressure manages to halt the relentless crush of gravity. |
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More articles:
Telescopes.com: Shop Telescopes and Telescope Eyepieces
Nicolaus Copernicus - Wikipedia, the free encyclopedia
Mercury (planet) - Wikipedia, the free encyclopedia
The Planet Jupiter
A Second Earth in Our Solar System [Life On Other Planets]
Famous Meteorites
Our Solar System
Our solar system consists of our sun, eight planets, the 166 known moons that orbit these eight planets, 3 dwarf planets and the four known moons that orbit them. Our solar system also includes billions of other small bodies such as asteroids, Kuiper belt objects, comets, meteoroids, and interplanetary dust.
In short, our solar system is made up of our sun and all the celestial objects that are gravitationally bound to it.
The general outline of our solar system is (from the center outward):
1. The sun
2. Four terrestrial inner planets (Mercury, Venus, Earth, and Mars)
3. An asteroid belt (made up of rocky objects)
4. Four outer planets (Jupiter, Saturn, Neptune, and Uranus)
5. The Kuiper belt (made up of icy objects)
6. Scattered disc (poorly understood region)
7. Heliopause (where the sun's solar wind is stopped by the interstellar medium)
8. And finally, a hypothetical Oort Cloud (there is a lot of ongoing debate about the Oort Cloud).
Yes, there was another planet called Pluto, but it is no longer considered a planet. Back in August 2006, the International Astronomical Union (IAU) in Prague decided that Pluto did not meet the requirements to be designated a planet, and it is now classified as one of many dwarf planets.
In the dim and dusty past, it was believed that the Earth was the center of the universe and that everything else revolved around it, including the sun. That theory changed as knowledge was gained. The telescope was invented, and men could see farther and farther.
The formation of our solar system remains a basis of contention between some religious leaders and some scientists. There are some of each who believe that God created the universe in six days, just the way creation is described in the book of Genesis in the Bible. There are others who subscribe to the "Big Bang" theory. The debate has been raging for decades and shows no signs of abating. But however our solar system came into being, it is magnificent!
Related Topics: The Planet Jupiter,
Guide to Buying a Telescope, Telescope Jargon
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