From UPSC perspective, the following things are important :
Prelims level : International Liquid Mirror Telescope (ILMT)
Mains level : Not Much
The four-meter International Liquid Mirror Telescope (ILMT) saw the first light recently, gazing out from its vantage on Devasthal, a hill in Uttarakhand.
What is the ILMT?
- The telescope has been built by a collaboration of scientists from Canada, Belgium and India.
- It is located at an altitude of 2,450 metres on the Devasthal Observatory campus of the Aryabhata Research Institute of Observational Sciences (ARIES) in Nainital district.
- A large pool of mercury placed in a vessel is spun around so fast that it curves into a parabolic shape. Since mercury is reflective, this shape helps in focusing the reflected light.
- Nearly 50 litres of mercury, weighing close to 700 kilograms, is spun hard to form a paraboloid mirror of just 4 mm thickness and a diameter of about 4 metres.
- A thin sheet of mylar protects the mercury from the wind.
- Once it starts making observations, the telescope will collect gigabytes of data, which will need to be analysed using artificial intelligence and machine learning (AI and ML) tools.
- The telescope will make sky surveys possible and obtain images that can help observe transient phenomena.
- It will help analyse events such as supernovae and record the presence of space debris or meteorites — basically, watch the skies.
What is the first image?
- The first image made by the telescope consisted of several stars and a galaxy, NGC 4274, which is 45 million light years away.
- The telescope, having a primary mirror that is liquid, cannot be turned and pointed in any direction.
- It “stares” at the zenith and watches the sky as the earth rotates, thereby giving a view of different objects.
- This property can be used to scan and survey the sky, and observe transients and moving objects such as meteorites.
- It will work in tandem with the existing 3.6-metre Devasthal Optical Telescope.