Webb Telescope Captures Weather on Exoplanet WASP-94A b

Why in the news?

Scientists using the James Webb Space Telescope observed weather patterns on the exoplanet WASP-94A b located nearly 700 light years away from Earth.

Key Highlights

• The study was published in the journal Science on May 21, 2026.
• Scientists detected:
  • Cloud formation
  • Atmospheric circulation
  • Dynamic weather cycles on the exoplanet.
• The exoplanet studied is:
  • WASP-94A b.

About WASP-94A b

• It is a Gas giant exoplanet.
• Nearly Twice the size of Jupiter.
• It has about half Jupiter’s mass.
• Completes one revolution around its star in Four days.

What are Hot Jupiters?

• “Hot Jupiters” are Massive gas giant exoplanets orbiting very close to their host stars.
• Characteristics:
  • Extremely high temperatures
  • Tidally locked rotation
  • One side permanently facing the star.

Tidally Locked Planets

A tidally locked planet has:

• Rotation period equal to revolution period.
• As a result:
  • One side remains permanently day side.
  • The other side remains permanently night side.

Weather on WASP-94A b

Scientists observed:

• Morning side: Clouds of magnesium silicate, iron and magnesium sulphide.
• Evening side: Relatively clear skies.

Clouds form on the cooler night side and move towards the hotter day side through powerful winds before dissipating.

How Were the Atmospheres Studied?

Scientists used:

• Spectroscopy
• Transit method

Spectroscopy

• Light from the host star is split into wavelengths.
• Atmospheric gases absorb specific wavelengths.
• This helps identify chemical compounds present in the atmosphere.

Transit Method

• The exoplanet passes in front of its host star.
• The atmosphere absorbs part of the starlight.
• Scientists analyse these changes to study atmospheric composition.

About the James Webb Space Telescope (JWST)

• Launched: December 2021.
• Joint project of:
  • NASA
  • ESA
  • CSA.
• Purpose:
  • Study the early universe
  • Exoplanets
  • Infrared astronomy.

About Extremely Large Telescope (ELT)

• Being built by the European Southern Observatory.
• Location: Northern Chile.
• Importance: May help discover more Earth like exoplanets and planetary systems.

[2017] What is the purpose of ‘evolved Laser Interferometer Space Antenna (eLISA)’ project?

[A] To detect neutrinos

[B] To detect gravitational waves

[C] To detect the effectiveness of missile defence system

[D] To study the effect of solar flares on our communication systems