More Earths there? Ahmedabad lab to probe exoplanets with new telescope

The Physical Research Laboratory (PRL) in Ahmedabad is getting ready to look deeper into space with a new, more powerful telescope that it plans to build by 2018. The PRL currently has a 1.2 meter telescope at the Gurushikhar observatory in Mt Abu. It now plans to build a 2.5-metre telescope which will be installed at the observatory after it is ready. Work on the new telescope is scheduled to start from April this year.Dr Abhijit Chakraborty of PRL’s Astronomy & Astrophysics department talked about the telescope project on Tuesday at a special session of the two-day workshop on ‘Current Trends in Radial-Velocity (RV) and Exoplanets’. He also talked about some of the technical challenges that would have to be overcome in building the new telescope.Dr Vishal Joshi, post-doctoral fellow at PRL, explained why the new telescope was important. He said that the power of a telescope depended on the diameter of its primary mirror which collects light coming from distant stars.The PRL’s current telescope at the Gurushikar observatory has a primary mirror of 1.2-metre diameter. Joshi said that a telescope with a primary mirror of 2.5 metre will have four-times the power of the 1.2-metre telescope to capture light from stars.“After the 2.5-metre telescope is installed at the observatory, we may be able to detect some exoplanets which could not be detected by the less powerful telescope. The new telescope will, of course, enhance other space-related observations. As of now, smaller exoplanets which orbit dim stars are very difficult to detect,” said Joshi.He further said that the new telescope will be able to collect light even from dim stars. “That would help us study the smaller exoplanets in other solar systems as well,” Joshi added.During the session, Dr. Chakraborty sought suggestions from national and international participants. He also said that PARAS – an instrument used to search for exoplanets — can also be attached to the proposed 2.5-metre telescope. The workshop concluded on Tuesday. The participants will be visiting the Mt Abu observatory on Wednesday.