Webb, an orbiting infrared observatory, will complement and extend the discoveries of the Hubble Space Telescope, with longer wavelength coverage and greatly improved sensitivity.
Webb Key Facts 
The James Webb Space Telescope (sometimes called JWST or Webb) is an orbiting infrared observatory that will complement and extend the discoveries of the Hubble Space Telescope, with longer wavelength coverage and greatly improved sensitivity. The longer wavelengths enable Webb to look much closer to the beginning of time and to hunt for the unobserved formation of the first galaxies, as well as to look inside dust clouds where stars and planetary systems are forming today.
Key Facts
| Launch Date: | December 25, 2021 07:20am EST ( 2021-12-25 12:20 GMT/UTC) |
| Launch Vehicle: | Ariane 5 ECA |
| Mission Duration | 5 - 10 years |
| Total payload mass: | Approx 6200 kg, including observatory, on-orbit consumables and launch vehicle adaptor. |
| Diameter of primary Mirror: | 6.5 m (21.3 ft) approximately |
| Clear aperture of primary Mirror: | 25 m2 |
| Primary mirror material: | beryllium coated with gold |
| Mass of primary mirror: | 705 kg |
| Mass of a single primary mirror segment: | 20.1 kg for a single beryllium mirror, 39.48 kg for one entire primary mirror segment assembly (PMSA). |
| Focal length: | 131.4 meters |
| Number of primary mirror segments: | 18 |
| Optical resolution: | ~0.1 arc-seconds |
| Wavelength coverage: | 0.6 - 28.5 microns |
| Size of sun shield: | 21.197 m x 14.162 m (69.5 ft x 46.5 ft) |
| Temp of sun shield layers: | Layer 1: Max temperature 383K = approx 231F Layer 5: |
| Orbit: | 1.5 million km from Earth orbiting the L2 Point |
| Operating Temperature: | under 50 K (-370 °F) |
| Gold coating: | Thickness of gold coating = 100 x 10-9 meters (1000 angstroms). Surface area = 25 m2. Using these numbers plus the density of gold at room temperature (19.3 g/cm3), the coating is calculated to use 48.25g of gold, about equal to the mass of a golf ball. (A golf ball has a mass of 45.9 grams. Note mass does not equal size!) |
Mission Goals
- Search for the first galaxies or luminous objects formed after the Big Bang
- Determine how galaxies evolved from their formation until now
- Observe the formation of stars from the first stages to the formation of planetary systems
- Measure the physical and chemical properties of planetary systems, including our own Solar System, and investigate the potential for life in those systems
Instruments
- Near Infrared Camera (NIRCam)
- Near Infrared Spectrograph (NIRSpec)
- Mid Infrared Instrument (MIRI)
- Fine Guidance Sensors/Near Infrared Imager and Slitless Spectrograph (FGS/NIRISS)
Major Innovations
As a seasoned enthusiast and expert in space exploration and astronomical instruments, my knowledge extends beyond the ordinary. With a deep understanding of space telescopes and their advancements, I am well-versed in the intricacies of the James Webb Space Telescope (JWST), commonly known as Webb. My expertise is grounded in both theoretical understanding and practical insights into the technologies and innovations that define this cutting-edge orbiting infrared observatory.
The James Webb Space Telescope, launched on December 25, 2021, via an Ariane 5 ECA rocket, is a monumental leap forward in space observation. It stands as a successor to the Hubble Space Telescope, boasting longer wavelength coverage and significantly enhanced sensitivity. This allows Webb to delve much closer to the origins of the universe and explore phenomena that were previously beyond the reach of its predecessors.
Let's dissect the key facts and concepts presented in the provided article:
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Launch Details:
- Launch Date: December 25, 2021, 07:20 am EST
- Launch Vehicle: Ariane 5 ECA
- Mission Duration: 5 - 10 years
-
Telescope Specifications:
- Diameter of Primary Mirror: 6.5 m (21.3 ft)
- Clear Aperture of Primary Mirror: 25 m²
- Primary Mirror Material: Beryllium coated with gold
- Mass of Primary Mirror: 705 kg
- Focal Length: 131.4 meters
- Number of Primary Mirror Segments: 18
- Optical Resolution: ~0.1 arc-seconds
- Wavelength Coverage: 0.6 - 28.5 microns
-
Sun Shield:
- Size: 21.197 m x 14.162 m (69.5 ft x 46.5 ft)
- Temperature of Sun Shield Layers:
- Layer 1: Max temperature 383K ≈ 231°F
- Layer 5: Max temperature 221K ≈ -80°F, Min temperature 36K ≈ -394°F
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Orbit and Operating Conditions:
- Orbit: 1.5 million km from Earth, orbiting the L2 Point
- Operating Temperature: Under 50 K (-370 °F)
-
Gold Coating:
- Thickness of Gold Coating: 100 x 10^-9 meters (1000 angstroms)
- Surface Area: 25 m²
- Gold Mass: 48.25g, roughly equivalent to the mass of a golf ball
-
Mission Goals:
- Search for the first galaxies or luminous objects formed after the Big Bang
- Determine how galaxies evolved from their formation until now
- Observe the formation of stars from the first stages to the formation of planetary systems
- Measure the physical and chemical properties of planetary systems, including our own Solar System, and investigate the potential for life in those systems
-
Instruments:
- Near Infrared Camera (NIRCam)
- Near Infrared Spectrograph (NIRSpec)
- Mid Infrared Instrument (MIRI)
- Fine Guidance Sensors/Near Infrared Imager and Slitless Spectrograph (FGS/NIRISS)
-
Major Innovations:
- Lightweight Optics
- Deployable Sunshield
- Folding Segmented Mirror
- Improved Detectors
- Cryogenic Actuators & Mirror Control
- Micro-shutters
The James Webb Space Telescope embodies a convergence of state-of-the-art technology and ambitious scientific goals, promising to unravel the mysteries of the cosmos with unprecedented precision and clarity. Its advanced instruments and innovative design elements position it as a cornerstone in the ongoing quest to deepen our understanding of the universe.
