In the last post “James Webb Space Telescope (part 1)“, we said we would explain how scientists are going to get the telescope into orbit and what the telescope will do that will define this telescope for generations to come, and that is exactly what we are going to do.
How are scientists getting the telescope into orbit?
Remember the telescope must get into space, unfold, and place itself into orbit 1,000,000 miles from Earth, all without any help from anything not already attached to it. This is how the telescope will go about putting itself into orbit.
- Put into space using a rocket completely folded inside the nose of that rocket weighing 14,000 pounds, just 1,000 pounds less than the maximum weight.
- Only the communication antenna with its computer will extend before it slingshots past the moon. The rest of the telescope will stay covered and protected and the small portion facing the sun will leave Earth with a heat shield.
- Once past the moon, the furthest man has traveled, the first paddle-like arm will unfold on one side, followed by an identical paddle-like arm on the opposite side.
- On each arm, two rolls, side by side, of the sunshield membrane begin to unroll. They will unroll only to the edges of both paddles on both sides
- At the edges of each paddle-like arm, the partially unrolled membrane attaches to a rod that will extend like an antenna. As it extends it will pull a matching side of the membrane from each arm away from the center like a sail climbing a mast. The rod will extend until the final diamond-shaped sunshield is completed. Tension wires tighten it in place.
- Now that the telescope is protected, the equipment can extend including a cryocooler that will drop the temperature of the equipment from roughly 30 degrees Fahrenheit to about -490 degrees Fahrenheit.
- The final step of opening the telescope is the 3-day process of unfolding the 18 octagon-shaped pieces of the large, parabolic mirror into place. It will be completed about 10 days before the telescope reaches its destination.
- Once it has reached its destination of 1 million miles from Earth, fueled rockets will set the telescope into orbit. These same rockets will be used for course corrections and orbit stabilization over the next 10 years. They are the life span of the telescope. There are attachment points for a mission to do repairs or refuel but no missions are anticipated.
Each step has to be absolutely precise. Each process has been checked, and rechecked to assure perfect performance. The heat shield must unroll perfectly, none of the equipment on board can be damaged, and the mirror can’t be misaligned. After all, they only get one chance to set up the most advanced telescope perfectly for it to be able to do its job.
What will the James Webb Space Telescope do?
Its instruments are observing areas 7 times the size Hubble could. Combine that with the distant orbit and __ equipment, Webb will be performing much more complicated analyses than Hubble.
- As we said before, space telescopes analyze light. Remember, light and time are related in such a way that the farther away the light can be observed, the closer to the time when something actually happened. Hubble was trying to determine what had already happened involving events that occurred 500 million years ago with its most recent upgrades, but the James Webb Space Telescope still be able to see further. It will be able to see up to events that occurred 200 million years ago.
- Even more amazing it will be able to use the light it sees to analyze the chemicals in the atmosphere of moons, planets, and stars far beyond our solar system! It will be able to determine if the atmosphere has the same air as our atmosphere. It will also be able to determine how much of each element is in those far away atmospheres. Those amounts will be compared to our atmosphere that has 78% nitrogen, 20% oxygen, 1% argon, and a bit of carbon dioxide before the smaller percentages of other elements mix together.
Between the size of the light particles it can see and its ability to see over half of the infrared portion of the light spectrum, the James Webb Space Telescope is sure to reveal answers to questions when it is launched in October of 2018. Questions we, as humans, have had since the beginning of time, including the ability to have life on another planet. Rest assured, as those answers come, so will more questions, making the future of the James Webb Space Telescope look very luminescent.