James Webb Space Telescope (JWST)

Introduction

The James Webb Space Telescope (JWST) is the most advanced space observatory ever built, launched by NASA in collaboration with ESA (European Space Agency) and CSA (Canadian Space Agency). Often referred to as the successor to the Hubble Space Telescope, JWST aims to explore the universe’s earliest galaxies, star formation, exoplanets, and even alien atmospheres.

Key Facts at a Glance

Feature	Details
Name	James Webb Space Telescope (JWST)
Agencies	NASA, ESA, CSA
Launch Date	25 December 2021
Launch Vehicle	Ariane 5 rocket (from French Guiana)
Cost	Approx. $10 billion
Orbit	Halo orbit around Sun-Earth Lagrange Point 2 (L2)
Wavelength Range	Infrared (0.6 to 28.3 microns)
Successor to	Hubble Space Telescope
Main Mirror Diameter	6.5 meters (compared to Hubble’s 2.4 meters)
Mission Duration (Expected)	Minimum 10 years

The co-alignment or non-coalignment of the orbits of the planet and the moon are used as parameters (using two angular parameters), and they can be used to model all the possible orbital alignments for a star-planet-moon system. Using these generic models and the analysis of photometric transit light curves of exoplanets that is being obtained by JWST, a large number of exomoons can be detected in near future. According to the researchers, an exo-moon around a gas giant planet like Jupiter in the habitable zone of the host star where temperature is appropriate for water to exist in liquid state may harbour life. Under favourable alignment of moon-planet-star, such exomoon may also be detected by JWST. The research has been accepted for publication in The Astrophysical Journal, which is published by the American Astronomical Society (AAS).

Objectives of JWST

JWST was designed with four major scientific goals:

1. Look back in time to the early universe:
   • Detect the first galaxies formed after the Big Bang.
   • Study the Epoch of Reionization.
2. Study galaxy formation and evolution:
   • Understand the birth and growth of galaxies.
3. Explore the life cycle of stars:
   • Observe star formation and planetary systems.
   • Investigate stellar nurseries obscured in visible light.
4. Study exoplanets and origins of life:
   • Analyze atmospheres of Earth-like exoplanets.
   • Look for biosignatures and potential habitability.

Instruments on Board

JWST carries four main scientific instruments:

Instrument	Full Form	Function
NIRCam	Near Infrared Camera	Captures high-resolution images in near-infrared.
NIRSpec	Near Infrared Spectrograph	Performs spectroscopy on up to 100 objects at once.
MIRI	Mid-Infrared Instrument	Observes colder, dustier objects and distant galaxies.
FGS/NIRISS	Fine Guidance Sensor/Near InfraRed Imager and Slitless Spectrograph	Ensures precise pointing and studies exoplanets.

Scientific Achievements (as of 2025)

• Oldest galaxies ever observed:
  • JWST detected galaxies that formed just 300 million years after the Big Bang, pushing back the observable timeline.
• Atmospheric analysis of exoplanets:
  • Detected water vapor, carbon dioxide, and methane in exoplanet atmospheres.
• Star birth and stellar nurseries:
  • Revealed breathtaking visuals of stellar nurseries like the Pillars of Creation in new light.
• Insight into planetary systems:
  • Uncovered protoplanetary disks, aiding in understanding solar system formation.

International Collaboration

Agency	Contribution
NASA	Lead developer and manager; provided spacecraft and launch services.
ESA	Provided launch vehicle (Ariane 5) and science instruments.
CSA	Provided Fine Guidance Sensor and scientific support.

How JWST Differs from Hubble ?

Parameter	Hubble Space Telescope	James Webb Space Telescope
Wavelength Range	Visible and ultraviolet	Infrared
Mirror Size	2.4 meters	6.5 meters
Orbit	Low Earth Orbit (LEO)	L2 (1.5 million km from Earth)
Main Focus	Stellar life cycle, galaxies	Early universe, exoplanets
Launch Year	1990	2021

India’s Relevance

While India is not a direct participant, JWST:

• Inspires India’s own missions like Astrosat and upcoming XPoSat.
• Encourages global science partnerships.
• Offers learning for ISRO’s future infrared astronomy missions.

India’s Strategic Opportunity

While not a partner in JWST, India can:

Opportunity	Description
ISRO Missions	Build upon JWST data to design better missions like Astrosat-2.
Scientific Diplomacy	Increase participation in global missions via policy dialogues and contributions.
Capacity Building	Train next-gen Indian astronomers and astrophysicists using JWST data.
Private Sector Role	Promote Indian space-tech firms in global value chains of instrumentation and data services.

Application in Education, Research, and Policy

Academic and Research Potential

• Universities worldwide are integrating JWST findings into curricula.
• Encourages interdisciplinary research across astronomy, physics, chemistry, and data science.
• Promotes innovations in machine learning algorithms for interpreting cosmic data.

Policy and Global Space Governance

• Sparks discussions on:
  • Sustainable space exploration
  • Intellectual property in global missions
  • Data sharing and open access in scientific missions
• Emphasizes the need for:
  • Space treaties update
  • International space traffic management

Challenges Faced

Challenge	Description
High Cost & Delays	Originally budgeted for $1 billion, ballooned to $10 billion with over a decade of delays.
Deployment Risks	Involved 300+ single-point failures; unfolded a tennis court-sized sunshield in space.
Maintenance Issues	Not serviceable due to its distant location at L2.
Infrared Interference	Requires extremely low temperatures (below 50K) to avoid interference.

Conclusion

The James Webb Space Telescope represents the pinnacle of human innovation, scientific ambition, and international cooperation. By peering into the farthest corners of the universe, it not only rewrites cosmic history but also opens new chapters for philosophical and ethical debates on our place in the cosmos.