Science and Technology
Context: Recently, Italian researchers have discovered a Dark Galaxy or Invisible Galaxy using Atacama Large Millimeter Array (ALMA).
About Dark Galaxy:
- It is termed invisible because the light emitted couldn’t be seen from the earth.
- The presence of the galaxy has been discovered using the gravitational lensing technique.
Gravitational lensing technique:
- It is an effect of Einstein’s theory of general relativity – simply put, mass bends light.
- The gravitational field of a massive object will extend far into space, and cause light rays passing close to that object to be bent and refocused somewhere else.
- It is discovered as compact.
- It is young and has interstellar dust.
- It is forming new stars at the rate of 1000 times the Milky Way.
Atacama Large Millimeter Array (ALMA):
- It is an international partnership of the European Southern Observatory (ESO), with U.S., Japan, Canada, Taiwan, Korea and Chile.
- It is the world’s largest ground-based facility for observations in the millimeter/submillimetre regime.
- It is a single telescope composed of 66 high precision antennas.
- It is located on the Chajnantor plateau, 5000 meters altitude in northern Chile.
- It allows scientists to unravel longstanding and important astronomical mysteries, in search of our Cosmic Origins.
Source: Livescience
Previous Year Questions
Q.1) Which one of the following statements best reflects the idea behind the “Fractional Orbital Bombardment System” often talked about in media? (2022)
- A hypersonic missile is launched into space to counter the asteroid approaching the Earth and explode it in space.
- A spacecraft lands on another planet after making several orbital motions.
- A missile is put into a stable orbit around the Earth and deorbits over a target on the Earth.
- A spacecraft moves along a comet with the same speed and places a probe on its surface.
Q.2) If a major solar storm (solar flare) reaches the Earth, which of the following are the possible effects on the Earth? (2022)
- GPS and navigation systems could fail.
- Tsunamis could occur at equatorial regions.
- Power grids could be damaged.
- Intense auroras could occur over much of the Earth.
- Forest fires could take place over much of the planet.
- Orbits of the satellites could be disturbed.
- Shortwave radio communication of the aircraft flying over polar regions could be interrupted.
Select the correct answer using the code given below:
- 1, 2, 4 and 5 only
- 2, 3, 5, 6 and 7 only
- 1, 3, 4, 6 and 7 only
- 1, 2, 3, 4, 5, 6 and 7
