Expansion of Universe

12 Dec 2024

Expansion of Universe

Recent data from NASA’s James Webb Space Telescope (Webb) has confirmed findings from the Hubble Space Telescope regarding the universe’s faster-than-expected expansion. 

More on the News

  • This  phenomenon of expansion is known as the Hubble Tension.
    • It poses problems as current scientific theories about how the universe has evolved cannot explain why it is expanding faster than expected.
    • It shows that there could be unknown forces or hidden elements influencing the cosmos.
  • Possible Explanations : Scientists have proposed some ideas, including:
    • Unique Properties of Gravity: Gravity might behave differently on a cosmic scale than we currently understand.
    • Hidden Matter or Energy: There could be unknown forms of energy or matter, such as dark radiation, which includes particles like neutrinos.
    • Limited Knowledge of Dark Matter and Dark Energy: Our understanding of these mysterious components, which make up most of the universe, may be incomplete.

Enroll now for UPSC Online Classes

How Did Scientists Measure the Universe’s Expansion?

Universe

  • Scientists used special stars called Cepheids to measure the distances to galaxies. 
    • These stars are like cosmic mile markers.
  • Both the Hubble and Webb telescopes observed these stars in many galaxies. 
    • Their measurements matched, showing that the measurements were accurate.
  • Webb, being a more powerful telescope, confirmed Hubble’s findings.
    • It  eliminated the possibility of errors in Hubble’s observations.

Historical Context

Universe

  • The Expanding Universe
    • The universe began with the Big Bang about 13-14 billion years ago.
    • In 1998, scientists discovered that this expansion is accelerating due to dark energy.
  • Award-Winning Research
    • Adam Riess, a Nobel laureate, co-discovered the accelerated expansion and is leading this study.

Key Findings  from NASA’s James Webb Space Telescope (Webb)

  • Faster Expansion of the Universe
    • The universe is expanding about 8% faster than predicted.
    • This discovery challenges current scientific models of how the universe works.
  • Role of Dark Energy and Dark Matter
    • Dark Energy: Makes up 69% of the universe and drives the accelerated expansion of space.
    • Dark Matter: Accounts for 27% of the universe, affecting visible objects like stars and planets through gravity.
  • The Hubble Constant
    • The Hubble constant measures the universe’s expansion speed.
    • Scientists expected a value of 67-68, but observations from Hubble and Webb show it at 73, with a possible range of 70-76.

Check Out UPSC NCERT Textbooks From PW Store

Challenges in Understanding the Hubble Tension

  • Dark Matter and Dark Energy: Limited knowledge and difficulty in observing these mysterious components make it hard to accurately model the universe’s expansion.
  • Measurement Errors: Issues like inaccurate telescope calibration, flawed data analysis methods, and unknown factors could affect the results.
  • Theoretical Gaps: Current cosmological models might be incomplete, and the tension may require entirely new physics to resolve.
  • Statistical Variations: Random data fluctuations or insufficient data could contribute to the discrepancy.
  • Unforeseen Challenges: Unexpected discoveries or unknown influences could further complicate understanding the universe’s expansion.

Need help preparing for UPSC or State PSCs?

Connect with our experts to get free counselling & start preparing

Aiming for UPSC?

Download Our App

# #
Quick Revise Now !
AVAILABLE FOR DOWNLOAD SOON
UDAAN PRELIMS WALLAH
Comprehensive coverage with a concise format
Integration of PYQ within the booklet
Designed as per recent trends of Prelims questions
हिंदी में भी उपलब्ध
Quick Revise Now !
UDAAN PRELIMS WALLAH
Comprehensive coverage with a concise format
Integration of PYQ within the booklet
Designed as per recent trends of Prelims questions
हिंदी में भी उपलब्ध

<div class="new-fform">






    </div>

    Subscribe our Newsletter
    Sign up now for our exclusive newsletter and be the first to know about our latest Initiatives, Quality Content, and much more.
    *Promise! We won't spam you.
    Yes! I want to Subscribe.