Astrae, the astronomy club of IISc, recently embarked on an expedition to capture the Milky Way
Dusk was just setting in and the early stars were twinkling when the bus carrying a bunch of students and faculty members rumbled into the Challakere campus of IISc, late one May evening. The visitors were part of Astrae, IISc’s astronomy club, and they were on a special expedition. After a quick dinner at the dining hall, the team proceeded to the guest house where accommodation for their night stay was arranged. But they were not planning to sleep much that night – with telescopes in hand, they had come to this faraway campus, with its pitch-black night sky clear of aerosols, to catch a glimpse of our home galaxy: the Milky Way.
Astrae was founded in early 2018 by four undergraduate students: Yash Mehta, Ameya Patwardhan, Divij Mishra and Ashim Dubey. It started with small group discussions in hostel rooms, and looking at constellations from the terrace of their hostel building. The students gradually organised themselves into a club, which soon attracted members from different batches and departments. Lectures and star-gazing sessions were organised and a 4-inch telescope was borrowed from the defunct PhD astronomy club. The new club thereafter expanded its activities, inviting faculty members and PhD students to give talks on astronomy-related topics.
The visit to Challakere in May was Astrae’s first expedition outside IISc’s Bangalore campus. About 24 club members, which largely included undergraduate students, plus a few PhD students and postdocs, and their mentor Aloke Kumar, Associate Professor in the Department of Mechanical Engineering, were on this trip. Aloke’s interest in astronomy developed during the long and monotonous lockdowns during COVID-19. He would observe the stars from his terrace, capturing them with his camera. After the lockdown, he shared snapshots from his newfound hobby with his undergraduate class. It was then that Kenil Ajudiya, a fourth-year undergraduate student, mentioned to him that they already had an astronomy club and that Aloke was welcome to join them. Kenil had just retrieved some telescopes that were in a deplorable state when the campus was desolate during the pandemic. He had taken them to the UG biology lab, and washed and cleaned them with Milli-Q water – water that is purified using reverse osmosis. Aloke’s association with Astrae had begun from this point.
The visit to Challakere in May was Astrae’s first expedition outside IISc’s Bangalore campus
Quest to capture the Milky Way
The devices that were carefully carried to Challakere included an 8-inch Newtonian Reflector telescope with a Dobsonian mount, a 5-inch Schmidt-Cassegrain telescope, a single motor drive, and a DSLR camera. Besides these, the club also has a 6-inch Newtonian Reflector telescope. Named after its inventor, Issac Newton, the Newtonian Reflector telescope is a vital tool for astronomers. It chiefly operates with two mirrors, a primary and a secondary. The 8-inch Newtonian Reflector telescope was bought by the club with sponsorship from a startup, Kalam labs, and some contributions from Aloke, Kenil and another club member, Hemansh Alkesh Shah. The 6-inch telescope was found abandoned by someone in the hostel, so the club members decided to take and use it. The club also occasionally uses much of Aloke’s personal equipment.
But just as the team prepared to set up the instruments on the terrace of the Challakere guest house, a drastic turn of events occured. It started raining heavily! The expedition now seemed like a washout.
It started raining heavily! The expedition now seemed like a washout
The heavy showers did not, however, deter the spirits of the club members. They decided to stay awake the entire night and observe the sky after the rain stopped and the clouds cleared. They gathered mattresses, snacks and juice for the long night, and camped out patiently in the hall, one of them occasionally stepping outside to check the sky. It was past midnight when the rains stopped. The students were finally able to set up their instruments on the terrace. But the wait was still not over. The sky was covered with thick clouds.
Finally, it was only at 3 am in the morning when the clouds slightly receded, giving a glimpse of the stars in the sky. The students got ready to take photographs of the galaxy; a smartphone was attached to the 8-inch telescope and the DSLR was mounted on the tripod. The team waited restlessly for the clouds to clear; some surveyed the sky with the help of an app called Stellarium to locate the direction of the constellations and the galaxy. In order to keep everyone busy during the long waiting period, Hemansh, a third-year undergraduate student and former convener of the club, gave an orientation on the night sky for the first-timers and hobby stargazers in the group. According to him, the ideal site to watch the night sky should be away from the city lights. Artificial lights in the city fill the sky with a diffused glow, called light pollution, which prevents proper viewing of the stars. A bright moon can also make it difficult to spot the stars, so a new moon or crescent moon is ideal.
The region of the sky visible at a particular time depends upon the viewer’s position. This is due to the Earth’s spherical shape and its rotation. However, if the sky is monitored throughout the night, a major portion of the total visible sky can be covered, leaving out only a small fraction that is closest to the Sun, and rises and sets with it. Hemansh adjusted the lenses of the telescope and showed the team several stellar bodies: the magnificent Messier 4 and Messier 80 – both globular clusters 6,000 and 30,000 light-years away respectively – and the Messier 13 or the Hercules globular cluster – 25,000 light-years away (a light-year is equivalent to about 9.5 trillion km). Globular clusters are stable, tightly bound clusters containing about a million stars. Besides these, Hemansh was also able to locate and show the group Messier 57 or the Ring Nebula, made up of leftover gases after a dying star blows out its outer layers. Other clusters that the team saw included Messier 20 or the Trifid Nebula, which is a region of gas actively collapsing on itself to create new stars, and Messier 24 or the Sagittarius Star Cloud, a region of the sky with an enormous density of stars.
But the students were yet to see what they had come all the way to Challakere for. The Milky Way still remained elusive behind thick clouds.
Then, at 4 am, the veil of clouds finally lifted, showing the shining stars fully. The telescope was adjusted, and the winsome Milky Way galaxy was finally visible. The team members took turns observing it, photographs were clicked, and an engaging discussion ensued upon its appearance. It was 5.30 am when a few members decided to catch some sleep; others preferred to go for a walk, exploring the vast campus. The expedition was finally a success.
Beyond the Milky Way
The visit to Challakere was the third major event that Astrae had organised in 2023 after CosmoGaze and CosmoExpo. CosmoGaze was organised in early February this year when a green-coloured comet hurtled past the Earth for the first time in 50,000 years. During the event, which was open to the public, the students also engaged in several discussions related to astronomy and showed visitors other objects like the Sun as well through their telescopes. Like the Challakere expedition, CosmoGaze too was initially racked with uncertainty. The crowd was losing hope as they were unable to locate the comet for a long time. But eventually, when it became visible, the whole crowd cheered!
CosmoExpo was an event held in April 2023 for middle school students, which featured talks by faculty members discussing their work and interest in astronomy, followed by observations of the sky.
Astrae’s present convenors are Deep Bhowmik, Atharv Sagar Suryawanshi, Sahil Sibasish Nandi and Gaurav Niraj Rachh, all undergraduate students at IISc. Their responsibilities include scheduling talks on various topics related to astronomy, organising events to popularise astronomy among the public, taking care of logistics for these events, and coordinating with the mentor and the UG office for issues like funds for equipment and events. They are keen on building upon the efforts of the previous conveners – Kenil, Hemansh, Harshvardhan and Ekta – who had put in a lot of effort to generate interest among students attending the talks and observation sessions, and had also taught about 50 students how to handle telescopes. Chaya Karkera, a postdoc at the Centre for Nano Science and Engineering, who was also part of the Challakere trip, believes that it would be helpful to increase the participation of girl students in these sessions. She says, “The club can host or collaborate with schools to introduce these events and conduct quizzes about astronomy to generate interest and competitive spirit among young girls.”
Aloke is confident that the club’s activities will grow and expand in the future. A faculty committee consisting of himself as well as Nirupam Roy from the Department of Physics, Baladitya Suri from the Department of Instrumentation and Applied Physics, and Ranjan Laha from the Centre for High Energy Physics, is looking at setting up an Astro-Imagery facility and observatory at IISc’s Bangalore campus, and an astronomy outreach programme at the IISc Challakere campus. An IISc alumnus living abroad, CK Manjunath, has also donated many sophisticated tools to the club.
One of the founders of the club, Ashim Kumar Dubey, who is currently pursuing his PhD at the Swiss Federal Institute of Technology, Lausanne, says that he continues to eagerly follow the activities of the club through social media. He is proud of the fact that his juniors have taken forward the efforts put in by the founders. The pictures of the Milky Way galaxy that he saw on the Instagram page of the club from the Challakere visit felt “like a true coming of age moment for the club.”
For many in the club, like Hemansh, the night sky is a source of inspiration, “a perfect balance of mystery, beauty, and capacity.” He says, “There are a lot of mysteries out there and beautiful objects to view. The fact that humans have managed to understand so much about them shows our capability.”
