stephen55
Literotica Guru
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Now that heavenly bodies have been mentioned and thus qualifying this topic for Lit...
The not yet completed or launched, James Webb Space Telescope will be the next thing in astronomy. The Hubble Space telescope is already past it's original expiry date and with the last servicing shuttle mission (May 2009), the extended lifetime of the satellite will likely come to an end in 2013. Without the space shuttle (for which Hubble was expressly designed to be launched and serviced) to allow boosting of the telescope`s orbit, Hubble will continue to slowly fall in altitude due to the almost imperceptible but real drag caused by the uppermost extent of earth`s atmosphere. Without any more service missions, the telescope satellite will eventually re-enter Earth`s upper atmosphere and go out in a blaze of fiery glory.
The James Webb Space Telescope (JWST) is tentatively planed to fly around 2018, that is, if Congress doesn`t cut the funding. Most of the 5.6 billion dollar budget has already been spent on basic design, engineering and initial component construction, but Congress has in the past saved a billion or so by writing off the several billion already spent on a project.
http://baltimorechronicle.com/2011/071711DefendScience.shtml
The Hubble Space telescope can be arguably said to have been the single most successful scientific instrument ever constructed. After an initial glitch with the primary mirror was fixed, giving the telescope an even better degree of resolution than originally planed, it went on to be part of more basic research and discovery than any other telescope in history. It truly is an example of a space mission that has succeeded beyond all original expectations.
However, all good things come to an end. With the advances in Earth based telescopes, particularly in mirror size, design and the use of adaptive optics, Hubble will soon no longer be able to give a return on operating costs that justifies it`s ongoing use. To do things that no newer Earth based telescope can do, NASA has to put a space telescope much farther from Earth and design it to be able to do things that the Hubble never could do.
First, when it comes to telescopes, bigger is definitely better. All a telescope (any telescope) does is capture light (photons) and bring them to a focus point. The bigger the photon collecting surface, the more photons you capture. The JWST will have a primary mirror about six and a half meters in diameter (seven and a half times the area of Hubble`s mirror).
Hubble is primarily an optical telescope in that it is designed to work for the most part in the same range of electromagnetic radiation (light) as the human eye. The JWST is going to work primarily in the infrared (heat) spectrum. It will be able to look back 13.4 billion years into history to see the very first galaxies forming and the very first stars beginning to shine.
With it`s large mirror and excellent resolution, the JWST will be able to visualize planets in our galaxy. If it were twenty-five light years away, it could see the Earth.
One problem is that in order to do it`s job the telescope must be very far away from the heat of the Earth. Because it will work primarily in the infrared, it must be seriously cold and shielded from infrared radiation from the sun and the Earth. The heat shield will be about the size of a football field.
The second and bigger problem is that no rocket in existence is big enough to carry a mirror that big, let alone a heat shield that big. It`s not the mass of the telescope but it`s size. So, what to do, what to do...
Build the thing so that it can be folded up for launch and then unfold when it gets there. Unfortunately, there is Sun-Earth Lagrange point 2, about a million and a half kilometers from Earth, four times the distance to the Moon. If there is a glitch and things don`t go as planned, the telescope will be far beyond any ability of NASA (or anyone) to get there and fix things. It is definitely a one-off proposition.
The not yet completed or launched, James Webb Space Telescope will be the next thing in astronomy. The Hubble Space telescope is already past it's original expiry date and with the last servicing shuttle mission (May 2009), the extended lifetime of the satellite will likely come to an end in 2013. Without the space shuttle (for which Hubble was expressly designed to be launched and serviced) to allow boosting of the telescope`s orbit, Hubble will continue to slowly fall in altitude due to the almost imperceptible but real drag caused by the uppermost extent of earth`s atmosphere. Without any more service missions, the telescope satellite will eventually re-enter Earth`s upper atmosphere and go out in a blaze of fiery glory.
The James Webb Space Telescope (JWST) is tentatively planed to fly around 2018, that is, if Congress doesn`t cut the funding. Most of the 5.6 billion dollar budget has already been spent on basic design, engineering and initial component construction, but Congress has in the past saved a billion or so by writing off the several billion already spent on a project.
http://baltimorechronicle.com/2011/071711DefendScience.shtml
The Hubble Space telescope can be arguably said to have been the single most successful scientific instrument ever constructed. After an initial glitch with the primary mirror was fixed, giving the telescope an even better degree of resolution than originally planed, it went on to be part of more basic research and discovery than any other telescope in history. It truly is an example of a space mission that has succeeded beyond all original expectations.
However, all good things come to an end. With the advances in Earth based telescopes, particularly in mirror size, design and the use of adaptive optics, Hubble will soon no longer be able to give a return on operating costs that justifies it`s ongoing use. To do things that no newer Earth based telescope can do, NASA has to put a space telescope much farther from Earth and design it to be able to do things that the Hubble never could do.
First, when it comes to telescopes, bigger is definitely better. All a telescope (any telescope) does is capture light (photons) and bring them to a focus point. The bigger the photon collecting surface, the more photons you capture. The JWST will have a primary mirror about six and a half meters in diameter (seven and a half times the area of Hubble`s mirror).
Hubble is primarily an optical telescope in that it is designed to work for the most part in the same range of electromagnetic radiation (light) as the human eye. The JWST is going to work primarily in the infrared (heat) spectrum. It will be able to look back 13.4 billion years into history to see the very first galaxies forming and the very first stars beginning to shine.
With it`s large mirror and excellent resolution, the JWST will be able to visualize planets in our galaxy. If it were twenty-five light years away, it could see the Earth.
One problem is that in order to do it`s job the telescope must be very far away from the heat of the Earth. Because it will work primarily in the infrared, it must be seriously cold and shielded from infrared radiation from the sun and the Earth. The heat shield will be about the size of a football field.
The second and bigger problem is that no rocket in existence is big enough to carry a mirror that big, let alone a heat shield that big. It`s not the mass of the telescope but it`s size. So, what to do, what to do...
Build the thing so that it can be folded up for launch and then unfold when it gets there. Unfortunately, there is Sun-Earth Lagrange point 2, about a million and a half kilometers from Earth, four times the distance to the Moon. If there is a glitch and things don`t go as planned, the telescope will be far beyond any ability of NASA (or anyone) to get there and fix things. It is definitely a one-off proposition.
