Context:
Astronomers detect a circumstellar disk around a star in the Large Magellanic Cloud (satellite galaxy of the Milky Way).
- Detection made using Atacama Large Millimeter/submillimeter Array (ALMA) telescope.
Star formation:
- Sun and other stars form when a dense clump of interstellar gas and dust collapses under its own gravitational pull.
- After a star is formed, the remaining dust and gas are trapped in orbit, forming a rotating disc or torus around the young star, known as a circumstellar disc.
- Newborn stars with circumstellar disks had been observed by astronomers only in the Milky Way galaxy until now.
- It helps in expanding the knowledge of understanding of high-mass star formation.
Atacama Large Millimeter/submillimeter Array (ALMA) telescope:
- A radio telescope comprising 66 antennas.
- Location – Atacama Desert of northern Chile (Chajnantor plateau, an altitude of 16,570 feet (5,050 metres) above sea level)
- An international partnership of –
- European Southern Observatory (ESO)
- U.S. National Science Foundation (NSF)
- National Institutes of Natural Sciences (NINS) of Japan
- NRC (Canada), MOST and ASIAA (Taiwan), and KASI (Republic of Korea) in cooperation with the Republic of Chile.
- Properties –
- Extraordinary sensitivity
- 66 antennas are equipped with a set of receivers that are designed to detect specific ranges of wavelengths on the electromagnetic spectrum.
- Uses a correlator which is a powerful supercomputer.
- Discoveries Made by ALMA –
- In 2013, ALMA discovered starburst galaxies that existed earlier in the universe’s history than previously thought.
- Detailed images of a protoplanetary disc around a young star, HL Tauri, in 2014, which challenged existing theories about planetary formation.
- In 2015, the telescope helped scientists observe the Einstein ring phenomenon, where light from a galaxy or star passes by a massive object on its way to Earth.
- Location of ALMA in Chile’s Atacama Desert
- Ideal for observing millimetre and submillimetre waves, which are highly susceptible to absorption by atmospheric water vapour on Earth.
- Advantages of the Atacama Desert
- Driest place on Earth
- Most nights are clear of clouds and free from moisture that can distort light.
Devasthal Observatory campus owned by Aryabhatta Research Institute of Observational Sciences (ARIES), Nainital in Uttarakhand has set-up the International Liquid-Mirror Telescope (ILMT), world’s first Liquid-Mirror Telescope (LMT) to be commissioned for astronomy and also one of its kind to be operational anywhere in the world.
Source: The Hindu
Previous Year Question
In the context of modern scientific research, consider the following statements about ‘IceCube’, a particle detector located at South Pole, which was recently in the news:
1. It is the world’s largest neutrino detector, encompassing a cubic kilometre of ice.
2. It is a powerful telescope to search for dark matter.
3. It is buried deep in the ice.
Which of the statements given above is/are correct?
[UPSC Civil Services Exam – 2015 Prelims]
(a) 1 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
Answer: (d)
