James Webb Space Telescope to launch on Christmas

[pecksniff]

Joy to the Cosmos!

NASA and space launch firm Arianespace have confirmed a launch date of December 25, at 7:20 AM Eastern Time, for the James Webb Space Telescope. On Thursday morning, the Ariane 5 rocket, with the telescope folded and stowed inside the payload fairings, left the assembly building at the launch facility in French Guiana and headed toward the pad. All indications are that, after more than two decades of planning, manufacture, setbacks, delays, cost overruns, and the eventual expenditure of over $10 billion, the most powerful instrument ever launched is finally about to take flight.

The complexity of the JWST is astounding. Rather than a single mirror, as in Hubble, Webb will have a 6.5m- (21’) wide mirror composed of 18 hexagonal gold-coated beryllium plates. Because the mirror is too large for any existing rocket, it will travel folded up, and deploy only when the telescope arrives on station. Unlike Hubble, that station won’t be in close orbit around Earth. Instead, Webb is bound for a point 1,500,000 km (930,000 miles) from Earth known as Lagrange Point 2 (L2), a spot where the gravity of the Earth and Sun are balanced so that anything near that spot can remain in orbit, holding position relative to Earth with minimum expenditure of energy.

It’s critical that Webb get away from Earth expressly because it’s an instrument that is designed to work mostly in the infrared—in the range of wavelengths we call “heat.” It’s going 1.5 million kilometers away, to an orbit where the Earth is eternally positioned between the telescope and the sun. There it will set, with its back to both Earth and Sun, as it deploys not just the folding mirror, but a whole series of massive sunshields, designed to keep heat from reaching the instruments. To work, Webb needs to be cold. Very cold. As in −223.2° C (−369.7° F) cold. Any warmer, and the delicate instruments will be overwhelmed; even damaged. One instrument has to be even cooler, just 7° C away from absolute zero, requiring an innovative “cryocooler” that cost $150 million to develop.

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After over 25 years of development, the anticipation for Webb is enormous. Hundreds of scientists have constructed theories that are waiting for data from Webb to be tested. Scientists are anticipating the potential to learn about everything from the early days of the universe to the potential for habitable worlds and the nature of dark matter. To say that thousands of careers are dependent on what happens over the next few days is a big underestimate of just how vital this instrument is to astronomers and others around the world.

 

[pecksniff]

And it launched without a hitch!

Almost . . .

Update: Santa has been destroyed by the range safety officer.

 

[rae121452]

now it only has to travel a million miles through space to be operational, if everything goes right. do you think it will send back pictures of god giving the finger?

 

[pecksniff]

now it only has to travel a million miles through space to be operational, if everything goes right. do you think it will send back pictures of god giving the finger?

Ideally, it will be, "Sorry for the inconvenience."

 

[pecksniff]

Update:

Engineers activating the James Webb Space Telescope fine-tuned its electrical power system to better cope with the actual space environment and cooled down slightly warmer-than-expected motors before pressing ahead Monday with final deployment of the observatory's critical sunshade.

Bill Ochs, the NASA project manager, said tightening up the sunshade's five hair-thin layers, carefully pulling them taut with motor-driven cables running through multiple pulleys, likely would take three days to complete. But by Monday night, three of the five layers had been pulled into shape, with the final two awaiting tightening Tuesday.

The sunshade deployment has long been considered one of Webb's most challenging hurdles, but "I don't expect any drama," Ochs said.

 

[pecksniff]

Webb telescope fully deployed!

Work for the James Webb Space Telescope is just beginning.

On Saturday (Jan. 8), the new observatory, the largest space telescope ever built, successfully unfolded its final primary mirror segment to cap what NASA has billed as one of its most complicated deployments in space ever. The Webb mission team is now turning its attention to directing the telescope to its final destination, while getting key parts of the observatory online for its astronomy work.

Webb is expected to arrive at its "insertion location" by Jan. 23, putting it in place to fire its engines to glide to a "parking spot" called Earth-sun Lagrange Point 2 (L2) about 930,000 miles (1.5 million kilometers) away from our planet. If Webb gets to the right zone, it can use a minimum of fuel to stay in place thanks to a near-perfect alignment with the sun, Earth and moon.

But it's not just maneuvers in space that the control teams will need to execute. Webb still has a lot of complex commissioning operations ahead, and NASA particularly pointed to aligning its mirror and getting its instruments ready as key milestones to watch for in the next few weeks.

As Webb prepares for the engine fire, team members will spend the next 15 days aligning the 18 mirror segments to "essentially perform as one mirror," John Durning, Webb's deputy project manager at NASA's Goddard Space Flight Center, told reporters Saturday (Jan. 8) in a press conference from Webb's control center at the Space Telescope Science Institute in Baltimore, Maryland.