An eye closes, another opens. Hubble space telescope famous, enjoying his last moments. His successor is called the James Webb. Much cheaper, easier, much larger, more accurate and scheduled for a more distant orbit than any other telescopes, James Webb sentenced to perfection.
In less than 10 years, will be launched the largest space telescope ever built. Its infrared detectors should help us discover ancient cosmological events. The telescope is an optical instrument that uses light reflection phenomenon on a concave mirror being used in astronomy for observing heavenly bodies. What is the difference James Webb space telescopes of the other? To approach it and analyze it.
Giant eye.
We'll start with the "eye" or: a primary mirror of 6.5 m diameter, larger than all terrestrial telescopes. What makes it special is that it is deformable and developed, because it could not be a question of also carrying a giant diameter in a missile. The eye is composed of 18 hexagonal pieces. Another innovation is spectacular thermal protection system. Under the mirror is a "sandwich" huge, consisting of five layers made of various materials. This shield is designed to decrease the temperature to 27º C at -223º C. Once in orbit, the satellite operates solar panels and antennas. Then side shields are starting to open up piece by piece.
What could beat who will soon overturn the hierarchy? Excessive heat. Therefore, NASA researchers have designed chose to install it in the coolest place possible orbit Lagrange point, the instrument will be, always, in the shadow of the Earth. Future telescope, very different in this respect from Hubble, will almost blind in order visibility usual, but with eyes wide open the infrared wavelengths between 0.6 and 28 micrometers (one micrometer equals 0.001 mm).
Another difficulty that welcomes Webb will be that its devices will radiate heat and particularly in this spectral range. The only solution would be cool tools in a drastically. Mirror is designed to operate at temperatures of -220º C, while the detectors are cooled to about -265º C, thanks to an additional cryogenic system. This innovative procedure has not been used before. Design, assembly and testing of Webb were performed over a 10-year record time considering the allocated period of similar construction is 50 years.
James Webb will be launched by Ariane 5 rocket telesatelitului journey to the place of observation will take about three months. Webb versus predecessor Hubble, Hubble was designed in the 70s and launched in 1990. The new telescope is superior in all respects. For James Webb was spent 1.5 million euros from 2.6 million as cost Hubble; red eyed giant weighs 5.4 tons to 12 of Hubble, but is 18 meters longer than its predecessor (30 m to 12 m); also, Webb is more accurate, thanks to its mirror with a diameter of 6.5 m (3 times larger than Hubble's mirror).
And finally, the successor will go far and will be placed in orbit around half a million kilometers from Earth. The conclusion is irrevocable: Webb will bring the information for which it was created. For Hubble there are only three options if the operating system will be improved Hubble, the satellite will "live" only four or five years. A recent report by NASA remembers that, every day, Hubble lose altitude, so in 2013 will crash to Earth.
Three scenarios have been proposed by experts. First, the old telescope work will last until 2010, Hubble with new missions scheduled in 2005 and even in 2010. A more optimistic is that the All 6 gyroscopes will be replaced, and longevity telescope will increase by another 20 years . Finally, catastrophic vision: an automatic task will go to Hubble, aiming attaching a system to make it fall on Earth, under the supervision of experts.
"Hubble has brought many benefits to science and humanity, James Webb has the potential to do the same thing he" ensure NASA. Webb wants an amazing machine, capable to travel in reverse time! Mirror to sweep an almost virgin space-time images of the universe and bring it looks as 300,000 years after the Big Bang. Visions infrared fact that Webb will see where nobody has ever seen before is because its infrared spectrometers. Looking Infrared Universe means looking at the old universe. Hubble was able to detect the weak glimpses of stars born at about 900,000 years after the Big Bang.
The giant red eyes might lead back with another 400-500 million years, working with a precision of at least 100 times greater than terrestrial detectors. "I have not seen primordial galaxies. With the help of James Webb, we hope to discover these elementary structures, which were chained to give birth later massive galaxies, "said astrophysicist Trinh Xuan Thuan, from the University of Virginia. Weather for 300,000 years after the Big Bang, the Universe calm reigned. The whole matter was composed of a mass "oily", consisting only of hydrogen and helium nuclei superfierbinti light, and thus kept several hundred million years.
Then, for a reason unknown composition began to cool and matter to aggregate, forming the first stars. They were different from those of today in the Milky Way is much higher. They were burning and exploding at the same time, which allowed the Universe to be sprinkled with heavier nuclei, then recovered by new stars. In addition, it will manage the new telescope, or penetrating eye, to lift the veil that covers one of the greatest mysteries of the universe: dark matter, hitherto remained invisible? Since the first images, we are promised a fireworks ...
FACTS
Hubble's History
1962. National Academy of Sciences USA recommended building a space telescope huge size.
1977. Congress passed granting funds to the project, and construction began Hubble Space Telescope.
1985. The telescope was completed. Mirror's weighed a ton.
April 25, 1990. Astronauts on shuttle Discovery launched the Hubble Telescope orbiting Earth. Hubble photographs sent but lacking focus.
December 1993. Hubble received "glasses". Endeavour shuttle astronauts repaired the telescope and attach a camera to correct its main mirror problems. New photos were clear and brought the first information from the ends of the universe.
June 1994. NASA has released images of the Orion nebula, which confirmed the formation of planets around stars that appeared after cooling "big" hydrogen and helium.
January 1996. Hubble came to over 1,500 images of galaxies in various stages of development, some 10 billion years old.
February 1997. A second mission of service. Astronauts have deleted some instruments of the telescope and added some "beds" in order to maintain the temperature.
November 13, 1999. The fourth gyroscope gave the Hubble Telescope. Because of the inability to focus, Hubble is closed, a new mission awaiting repair.
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