China launches new satellite for violent cosmic phenomena observation

Prelims Previous Year Question: (2018):

Q. Consider the following phenomena

1. Light is affected by gravity.

2. The Universe is constantly expanding.

3. Matter warps its surrounding space-time.

Which of the above is/are the prediction/predictions of Albert Einstein’s General Theory of Relativity, often discussed in the media ?

(a) 1 and 2 only

(b) 3 only

(c) 1 and 3 only

(d) 1, 2 and 3

Answer: (d)

Numerous predictions stemming from the General theory of Relativity have been substantiated through observational evidence.

Gravity’s influence on light:

• • One prominent prediction of General Relativity is the bending of light due to gravity, commonly referred to as gravitational lensing.

• • This phenomenon has been observed across various astrophysical scenarios, such as the distortion of light around massive galaxies and the alteration of cosmic microwave background radiation by large-scale structures in the universe.

• • A pivotal confirmation occurred during a solar eclipse in 1919 when stars near the sun appeared slightly shifted, affirming that the sun’s gravity had indeed bent the light’s path.

Expanding universe:

• • Another forecast of General Relativity is the concept of an expanding universe.

• • Initially, Einstein introduced a ‘cosmological constant’ to maintain a static universe but later discarded it when observational evidence confirmed the universe’s expansion.

• • This expansion has been verified through multiple observations, including the redshift of light from distant galaxies and the presence of cosmic microwave background radiation.

Matter warping spacetime:

• • General Relativity posits that massive objects distort the fabric of spacetime around them, causing nearby objects to traverse curved paths—a phenomenon known as gravitational curvature.

• • This prediction has undergone validation through various observational tests, encompassing the precession of Mercury’s orbit, the bending of light around massive entities, and the detection of gravitational waves.

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Practice Question for Prelims:

Q. Consider the following statements:

1. ‘Einstein Probe’ Satellite has been launched by National Aeronautics and Space Administration (NASA) in collaboration with European Space Agency (ESA).

2. ‘Einstein Probe’ employs the astronomical time-domain observation method, conducting a real-time dynamic sky survey in a soft X-ray band.

Which of the statements given above is/are correct?

(a) 1 only

(b) 2 only

(c) Both 1 and 2

(d) Neither 1 nor 2

Answer: (b)

Statement 1 is not correct: China made a significant stride in space exploration by launching a revolutionary astronomical satellite, the Einstein Probe (EP), designed in the shape of a lotus. This groundbreaking initiative aims to delve into mysterious transient phenomena in the universe. The Long March-2C carrier rocket lifted off, carrying the EP into its planned orbit. Collaborating in this ambitious space exploration endeavour are the European Space Agency and the Max Planck Institute for Extraterrestrial Physics in Germany, showcasing the global significance of EP’s mission.

Statement 2 is correct: The EP utilizes cutting-edge X-ray detection technology. The lotus-inspired design incorporates 12 ‘petals’ housing wide-field X-ray telescopes (WXT) and two ‘stamens’ containing follow-up X-ray telescopes (FXT). Together, these components form a space observatory with the primary objective of capturing the initial light emitted during supernova explosions and exploring the nature of transient celestial objects at the outer reaches of the universe. Designed with a lifespan of five years, the Einstein Probe employs the astronomical time-domain observation method, conducting a high-sensitivity real-time dynamic sky survey in the soft X-ray band.