nasa 2 jaar geleden

James Webb Space Telescope | 25-12-2021 / 25-01-2022

The James Webb Space Telescope (JWST) has launched from the Guiana Space Center in Kourou, French Guiana. More than 20 years in the making, JWST’s observations of the cosmos will change our understanding of the universe.

With revolutionary technology, the $10 billion Webb Space Telescope will observe a part of space and time never seen before, providing a wealth of amazing views into an era when the very first stars and galaxies formed  over 13.5 billion years ago.


It can explore our own solar system’s residents with exquisite new detail and study the atmospheres of distant worlds. From new forming stars to devouring black holes, Webb will reveal all this and more! It’s the world’s largest and most powerful space telescope ever built.


Webb is an international collaboration between NASA, ESA (European Space Agency), and CSA (Canadian Space Agency). Thousands of engineers and hundreds of scientists worked to make Webb a reality, along with over 300 universities, organizations, and companies from 29 U.S. states and 14 countries!


25-12-2021 | Launch Date

Webb successfully launched on December 25, 2021 07:20am EST ( 2021-12-25 12:20 GMT/UTC).


Launch Vehicle

The James Webb Space Telescope was launched on an Ariane 5 rocket. The launch vehicle is part of the European contribution to the mission. The Ariane 5 is one of the world's most reliable launch vehicles capable of delivering Webb to its destination in space.


Launch Location

Webb was launched from Arianespace's ELA-3 launch complex at European Spaceport located near Kourou, French Guiana. It is beneficial for launch sites to be located near the equator - the spin of the Earth can help give an additional push. The surface of the Earth at the equator is moving at 1670 km/hr.


Webb Launch Configuration

For the telescope to fit into the rocket, it had to be folded up.


26-12-2021 | Antenna

Webb successfully deployed a critical antenna Sunday (Dec. 26) just one day after its Christmas launch into space.


The space telescope unfolded what scientists call a gimbaled antenna assembly that carries the high-rate data dish responsible for beaming Webb's observations of the early universe back to Earth.


"This antenna will be used to send at least 28.6 Gbytes of science data down from the observatory, twice a day," NASA officials wrote in a mission update. "The team has now released and tested the motion of the antenna assembly - the entire process took about one hour."


28-12-2021 | Unitized Pallet Structure

On Tuesday (Dec. 28), the spacecraft notched another key step in that deployment as it unfolded the Forward Unitized Pallet Structure (UPS) of its vast sunshield, according to a NASA statement. The process took four hours and concluded at 1:21 p.m. EST (1821 GMT), according to the agency.


29-12-2021| Deployable Tower Assembly

Shortly after 9:00 a.m. EST, engineering teams began the process of extending Webb’s Deployable Tower Assembly (DTA). When deployed, the DTA will create space between the spacecraft and the telescope, to allow for better thermal isolation and provide room for the sunshield to deploy.


30-12-2021 | AFT Momentum Flap

The Webb telescope and science instruments are ready to enter the shade, never again to see direct sunlight. One of Webb’s unique design features is using passive cooling by a five-layer sunshield to reach the telescope’s operational temperatures of 45 Kelvin (-380 degrees Fahrenheit).


Shortly after 9 a.m. EST, the Webb team completed deployment of the observatory’s aft momentum flap. In a process that took about eight minutes, engineers released the flap’s hold-down devices, and a spring brought the flap into its final position.


31-12-2021 | Sunshield Mid-Booms Deploys

The Webb mission operations team has extended the first of the sunshield’s two “arms” – the port (left side) mid-boom.


The critical step of the port mid-boom deployment was scheduled to begin earlier in the day. However, the team paused work to confirm that the sunshield cover had fully rolled up as the final preparatory step before the mid-boom deployment.


The deployment of the five telescoping segments of the motor-driven mid-boom began around 1:30 p.m. EST, and the arm extended smoothly until it reached full deployment at 4:49 p.m.


Engineers began to deploy the second (starboard) mid-boom at 6:31 p.m. EST and completed the process at about 10:13 p.m. EST.


With the successful extension of Webb’s second sunshield mid-boom, the observatory has passed another critical deployment milestone. Webb’s sunshield now resembles its full, kite-shaped form in space.


01-01-2022 | Webb Sunshield Tensioning Begins

Work on the deployment of Webb’s sunshield mid-booms went late into the night. Webb mission management decided to pause deployment activities for 01-01-2022 and allow the team to rest and prepare to begin Webb’s sunshield tensioning on Sunday, Jan. 2.


02-01-2022 | Deployment Timeline Adjusted as Team Focuses on Observatory Operations

The Webb team has decided to focus today on optimizing Webb’s power systems while learning more about how the observatory behaves in space. This will ensure Webb is in prime condition to begin the next major deployment step in its unfolding process.  


“We’ve spent 20 years on the ground with Webb, designing, developing, and testing,” said Mike Menzel, of NASA’s Goddard Space Flight Center, Webb’s lead systems engineer. “We’ve had a week to see how the observatory actually behaves in space. It’s not uncommon to learn certain characteristics of your spacecraft once you’re in flight. That’s what we’re doing right now."


03-01-2022 | First Layer of Webb’s Sunshield Tightened

The Webb team finished tensioning the first layer of the observatory’s sunshield at 3:48 pm EST, that is, tightening it into its final, completely taut position. This is the first of five layers that will each be tightened in turn over the next two to three days, until the observatory’s sunshield is fully deployed. The process began around 10 am EST.


This layer is the largest of the five, and the one that will experience the brunt of the heat from the Sun. The tennis-court-sized sunshield helps keep the telescope cold enough to detect the infrared light it was built to observe.


03-01-2022 | Second and Third Layers of Sunshield Fully Tightened

The Webb team has completed tensioning for the first three layers of the observatory’s kite-shaped sunshield, 47 feet across and 70 feet long.


The team began the second layer at 4:09 pm EST, and the process took 74 minutes. The third layer began at 5:48 pm EST, and the process took 71 minutes. In all, the tensioning process from the first steps this morning until the third layer achieved tension took just over five and a half hours.


“This was the hardest part to test on the ground, so it feels awesome to have everything go so well today. The Northrop and NASA team is doing great work, and we look forward to tensioning the remaining layers.”


04-01-2022 | Webb Team Tensions Fifth Layer, Sunshield Fully Deployed

At approximately 11:59 am EST, the fifth and final layer of Webb’s sunshield was fully tensioned, marking the completion of sunshield deployment, a key milestone in preparing it for science operations.


“This is the first time anyone has ever attempted to put a telescope this large into space,” said Thomas Zurbuchen, associate administrator for NASA’s Science Mission Directorate at the agency’s headquarters in Washington.


The five-layered sunshield will protect the telescope from the light and heat of the Sun, Earth, and Moon. Each plastic sheet is about as thin as a human hair and coated with reflective metal, providing protection on the order of more than SPF 1 million. Together, the five layers reduce exposure from the Sun from over 200 kilowatts of solar energy to a fraction of a watt.


This protection is crucial to keep Webb’s scientific instruments at temperatures of 40 kelvins, or under minus 380 degrees Fahrenheit – cold enough to see the faint infrared light that Webb seeks to observe.


“Unfolding Webb’s sunshield in space is an incredible milestone, crucial to the success of the mission,” said Gregory L. Robinson, Webb’s program director at NASA Headquarters. The team has accomplished an audacious feat with the complexity of this deployment – one of the boldest undertakings yet for Webb.”


05-01-2022 | Secondary Mirror Deployment Confirmed

Webb teams successfully deployed the observatory’s secondary mirror support structure. When light from the distant universe hits Webb’s iconic 18 gold primary mirrors, it will reflect off and hit the smaller, 2.4-foot (.74-meter) secondary mirror, which will direct the light into its instruments.


“Another banner day for JWST,” said Bill Ochs, Webb project manager at NASA’s Goddard Space Flight Center, as he congratulated the secondary mirror deployment team at the Mission Operations Center in Baltimore. “This is unbelievable… We’re about 600,000 miles from Earth, and we actually have a telescope.”


The deployment process began at approximately 9:52 a.m. EST, and the secondary mirror finished moving into its extended position at about 11:28 a.m. EST. At approximately 12:23 p.m. EST, engineers confirmed that the structure was fully secured and locked into place and the deployment was complete.


“The world’s most sophisticated tripod has deployed,” said Lee Feinberg, optical telescope element manager for Webb at Goddard.


06-01-2020 | Webb’s Specialized Heat Radiator Deployed Successfully

At about 8:48 a.m. EST, a specialized radiator assembly necessary for Webb’s science instruments to reach their required low and stable operating temperatures deployed successfully.


The deployment of the ADIR – a process that released a lock to allow the panel to spring into position – took about 15 minutes.


07-01-2022 | First of Two Primary Mirror Wings Unfolds

Engineers have begun the final stage of Webb’s major structural deployments: the unfolding of its two primary mirror wings. These side panels, which were folded back for launch, each hold three of the observatory’s 18 hexagonal, gold-coated mirror segments.


Webb’s iconic primary mirror is taking its final shape. Today, the first of two primary mirror wings, or side panels, was deployed and latched successfully. Each side panel holds three primary mirror segments that were engineered to fold back to reduce Webb’s overall profile for flight.


The process of deploying the port side mirror wing began at approximately 8:36 a.m. EST. At approximately 2:11 p.m. EST, engineers confirmed that the panel was fully secured and locked into place, and the deployment was complete.


Now that the port side wing panel is locked in place, ground teams will prepare to deploy and latch the starboard (right side) panel tomorrow. Upon completion, Webb will have concluded its major deployment sequence.


08-01-2022 | Primary Mirror Wings Successfully Deployed, All Major Deployments Complete

The Webb mission operations team has given the ‘go-ahead’ to move forward with the extension of its starboard primary mirror panel. This is the last of the major deployments on the observatory, and its completion will set the stage for the remaining five and a half months of commissioning, which consist of settling into stable operating temperature, aligning the mirrors, and calibrating the science instruments.

At 1:17 p.m. EST, NASA’s James Webb Space Telescope completed all of its large-scale deployments with the extension and latching of its starboard primary mirror wing. Now that the telescope is structurally fully deployed – with the secondary mirror tripod and both primary mirror wings in place – the three-month process of aligning all of Webb’s telescope optics into a precise system can now commence!


12-01-2022 | Webb Begins Its Months-Long Mirror Alignment

Webb has begun the detailed process of fine-tuning its individual optics into one huge, precise telescope.


Engineers first commanded actuators – 126 devices that will move and shape the primary mirror segments, and six devices that will position the secondary mirror – to verify that all are working as expected after launch. The team also commanded actuators that guide Webb’s fine steering mirror to make minor movements, confirming they are working as expected. The fine steering mirror is critical to the process of image stabilization.


Ground teams have now begun instructing the primary mirror segments and secondary mirror to move from their stowed-for-launch configuration, off of snubbers that kept them snug and safe from rattling from vibration. These movements will take at least ten days, after which engineers can begin the three-month process of aligning the segments to perform as a single mirror.


13-01-2022 | Mirror, Mirror…On Its Way!

With major deployments complete, Webb continues its journey to its final halo orbit around L2. In the meantime, there are several smaller deployments in the next couple of weeks, which constitute the beginning of a several-month phase of aligning the telescope’s optics.


We have started the process of moving the mirror segments (all primary plus secondary) out of their stowed launch positions. For more details, here is Marshall Perrin from the Space Telescope Science Institute, home of the Webb Mission Operations Center:


19-01-2022 | Webb Mirror Segment Deployments Complete

The James Webb Space Telescope team completed the mirror segment deployments. As part of this effort, the motors made over a million revolutions this week, controlled through 20 cryogenic electronics boxes on the telescope.


The mirror deployment team incrementally moved all 132 actuators located on the back of the primary mirror segments and secondary mirror. The primary mirror segments were driven 12.5 millimeters away from the telescope structure.


Using six motors that deploy each segment approximately half the length of a paper clip, these actuators clear the mirrors from their launch restraints and give each segment enough space to later be adjusted in other directions to the optical starting position for the upcoming wavefront alignment process.


21-01-2022 | Webb’s Journey to L2 Is Nearly Complete

On Monday, Jan. 24, engineers plan to instruct NASA’s James Webb Space Telescope to complete a final correction burn that will place it into its desired orbit, nearly 1 million miles away from the Earth at what is called the second Sun-Earth Lagrange point, or “L2” for short.



Unfolding the telescope

► JWST is big! The main mirror, made up of 18 hexagonal mirror segments, is 6.5 meters (21 feet) wide, a hefty increase over the 2.4 meters of the Hubble Space Telescope. And the sunshield that protects JWST’s mirrors from the warmth of the Sun, Earth, and Moon is even larger: 22 by 10 meters – comparable in size to a regulation tennis court.


► To fit inside the rocket fairing (the compartment that will hold JWST as it is launched), both the mirror and the sunshield were folded up in a complex pattern of space origami. More importantly, both the mirror and sunshield must unfold successfully after launch for JWST to become fully functional.


► JWST’s destination is the Earth-Sun Lagrange 2 point. After launch, it will take 29 days for the telescope to reach L2, and that month is characterized by NASA as “29 days on the edge.”


► During this month, JWST will go through a carefully choreographed sequence of “deployments” of its major structural components: unfurling its solar panels, deploying an antenna, and then beginning the slow process of sunshield deployment. After the sunshield is in place, the secondary mirror swings into place, and the wings of the primary mirror fold out.


Post Launch Deployment

After launch, the telescope will deploy on its 30-day, million-mile journey out to the second Lagrange point (L2). The video beneath shows the deployment procedure, timeline, and location of the satellite during deployment. More about the telescope's final orbit around L2.


The First Images

The world’s largest and most complex space science observatory has another 5 1/2 months of setup still to come, including deployment of the primary mirror wing, alignment of the telescope optics, and calibration of the science instruments. After that, Webb will deliver its first images.


The telescope’s revolutionary technology will explore every phase of cosmic history – from within our solar system to the most distant observable galaxies in the early universe, to everything in between. Webb will reveal new and unexpected discoveries and help humanity understand the origins of the universe and our place in it.




Additional Details

The Launch Segment has 3 primary components:


1. Launch Vehicle: an Ariane 5 with the cryogenic upper stage. It will be provided in the single launch configuration, with a long payload fairing providing a maximum 4.57 meter static diameter and useable length of 16.19 meters.


2. Payload Adapter, comprising the Cone 3936 plus ACU 2624 lower cylinder and clamp-band, which provides the separating mechanical and electrical interface between the Webb Observatory and the Launch Vehicle.


3. Launch campaign preparation and launch campaign. The launch campaign preparation and launch campaign is the mutual responsibility of NASA, ESA, NGAS, and Arianespace.


Why Doesn’t Webb Have Deployment Cameras?

As NASA’s James Webb Space Telescope makes its way out to its intended orbit, ground teams monitor its vitals using a comprehensive set of sensors located throughout the entire spacecraft. Mechanical, thermal, and electrical sensors provide a wide array of critical information on the current state and performance of Webb while it is in space.


A system of surveillance cameras to watch deployments was considered for inclusion in Webb’s toolkit of diagnostics and was studied in-depth during Webb’s design phase, but ultimately this was rejected.


“Adding cameras to watch an unprecedently complicated deployment of such a precious spacecraft as Webb sounds like a no-brainer, but in Webb’s case, there’s much more to it than meets the eye,” said Paul Geithner, deputy project manager – technical for the Webb telescope at NASA’s Goddard Space Flight Center. “It’s not as straightforward as adding a doorbell cam or even a rocket cam.”


First of all, Webb is big, undergoes many configuration changes during deployment, and has many specific locations of import to deployment. Monitoring Webb’s deployments with cameras would require either multiple narrow-field cameras, adding significant complexity, or a few wide-field cameras that would yield little in the way of helpful detailed information. Wiring harnesses for cameras would have to cross moving interfaces around the observatory and add more risk of vibrations and heat leaking through, presenting a particular challenge for cameras located on the cold side of Webb.


Then there’s the issue of lighting. Webb is very shiny, so visible cameras on the Sun-facing side would be subject to extreme glare and contrast issues, while ones on the cold, shaded side would need added lighting. Although infrared or thermal-imaging cameras on the cold side could obviate the need for illumination, they would still present the same harnessing disadvantages. Furthermore, cameras on the cold side would have to work at very cold cryogenic temperatures. This would either require ‘ordinary’ cameras to be encapsulated or insulated so they would work in extreme cold, or development of special-purpose cryogenic-compatible cameras just for deployment surveillance.


Notwithstanding these challenges, engineers mocked up and tested some camera schemes on full-scale mockups of Webb hardware. However, they found that deployment surveillance cameras would not add significant information of value for engineering teams commanding the spacecraft from the ground.


“Webb’s built-in sense of ‘touch’ provides much more useful information than mere surveillance cameras can,” said Geithner. “We instrumented Webb like we do many other one-of-a-kind spacecraft, to provide all the specific information necessary to inform engineers on Earth about the observatory’s health and status during all activities.” Engineers can also correlate years of data from ground testing with telemetry data from flight sensors to insightfully interpret and understand flight sensor data.


https://blogs.nasa.gov/webb


NASA
nasa