A summary of the lunar eclipse event at the ICTS Campus on 7th September 2025.
On 7th September 2025, a full moon crept into the shadow of the Earth and emerged back. In India, this phenomenon – the lunar eclipse – was clearly visible to our eyes from around 9:58 PM to around 1:26 AM. At the total eclipse between 11:00 PM to 12:22 AM, one could see the Moon with a pale red hue – a phenomenon called the ‘blood moon’.
The ICTS campus came alive on the evening of 7th September as people living around visited for a lunar eclipse event. From 5 PM to 7 PM, we engaged with information about our Moon, the lunar eclipse, and the events in our solar system, after which we dispersed. Sanjana Anand from Visvesvaraya Industrial and Technological Museum gave a talk from 5 PM to 6 PM, and hands-on activities followed from 6 PM to 7 PM. The Outreach team of ICTS, in association with the ICTS Astro club, coordinated the event.
The Science Behind Lunar Eclipses
What Is a Lunar Eclipse?
A lunar eclipse happens when Earth moves directly between the Sun and the Moon. This blocks the sunlight and casts Earth’s shadow onto the Moon. During this total lunar eclipse, the Moon often turns reddish orange, which is why people call it a “Blood Moon.”
Why Don’t We See a Lunar Eclipse Every Month?
We get a full moon every month, so you might think Earth’s shadow would fall on the Moon every month, too. But lunar eclipses only happen a few times each year. The reason is that the Moon’s orbit is tilted at about 5 degrees compared to Earth’s path around the Sun. Imagine Earth orbiting on a flat table, but the Moon goes around Earth on a slight slope, sometimes above the table and sometimes below it. Most of the time, Earth’s shadow passes above or below the Moon. Only when everything lines up perfectly does a lunar eclipse happen. Watch a video about the Lunar Eclipse.
Why Is Observing Lunar Eclipses Important?
Watching a lunar eclipse is both beautiful and educational. Long ago, ancient Greek scientists figured out that the Earth is round by watching the curved shadow it makes on the Moon. Today, scientists study lunar eclipses to learn about our atmosphere. The red colour tells us about gases and particles in the air.
For students, observing an eclipse connects classroom lessons to real life. It helps us understand how Earth, the Moon, and the Sun work together in space. Plus, unlike solar eclipses, lunar eclipses are completely safe to watch with just your eyes, making them perfect for everyone to enjoy.
Talk from VITM Personnel
Sanjana Anand from the Visvesvaraya Industrial and Technological Museum (VITM) delivered a talk in Kannada. Titled ’The Moon’s Journey: Story of Our Celestial Neighbour’, the talk drew from local culture and science alike. She talked about the Moon – ‘seas’ in the Moon, eclipses, and the cause of the blood moon. The talk also featured activities, including working models of the Sun-Earth-Moon system and crosswords, to inspire ideas from the audience about shadow formation, how eclipses happen, etc.
Sanjana also assured that the lunar eclipse does not affect food or water – the eclipse is just a play of light and shadows. The lunar eclipse does not create any new rays. If anything, she said, the Moon is getting fewer rays from the Sun at this time.
The talk was followed by an activity session for the visitors. The activities covered ideas about the phases of the Moon, the Moon’s surface, the lunar eclipse, and the Moons of other planets. Volunteers from ICTS facilitated the activities.
Exploring the Phases of the Moon with a Torch and a Football
A simple activity with a ball and a torch illustrated why we see the phases of the Moon change every day. A ball represented the Moon, a torch the sun, and the participant an observer on the Earth. The torch would remain fixed and shining on the observer, who would rotate with the ball. Depending on where the ball is in relation to the observer and the torch, one could see different phases of the Moon.
Realising the Moon Phases with Cookies
We provided images of different phases of the Moon and gave the kids a task to recreate those phases of the Moon using cookies, which they did pretty well!
Craters of the Moon
Another activity showed how craters form on the Moon when meteors strike. We created possible surfaces of the Moon using layers of different kinds of powders. They differed in lightnesses and textures, for example, brick powder, rangoli powder, maida, etc. The kids threw stones from various heights and angles at the layers to form various craters and ejecta patterns. This is comparable to the patterns we see when we look at the Moon.
Eclipse in a Cup: Why Eclipses Are So Rare
We demonstrated a simple model that answers a puzzling question: why doesn’t the Moon eclipse the Sun every month?
Using just three plastic cups, modelling clay, a tennis ball, and a pushpin, participants built a scaled model of the Earth, Moon, and Sun system. The key insight is that the Moon’s orbital plane is tilted roughly 5 degrees relative to Earth’s orbit around the Sun.
We rolled two clay spheres, one for Earth and a smaller one for the Moon. Earth sat atop a trimmed cup at midpoint height. A second cup marked the ecliptic plane with a pushpin showing Earth’s position. The third cup, with a line drawn slightly above the table, represented the Moon’s tilted orbit.
When participants rotated the Moon around Earth twelve times per year while keeping the tilt fixed, something striking happened. All three bodies are lined up only twice annually. These rare alignments, when the tilted lunar orbit crosses the ecliptic plane at precisely new or full Moon, are the only times eclipses can occur.
The Moon’s 5.14-degree tilt means its shadow usually passes above or below Earth, and Earth’s shadow typically misses the Moon. Only during brief two-week windows when the orbital planes align do eclipses become possible.
A DIY enthusiast can find more details here, along with a detailed video walkthrough of the activity.
What made this activity work was its hands-on nature. Rather than viewing diagrams, participants physically moved the model, building intuition for why celestial mechanics produces eclipses so rarely. The hand-built model transformed an abstract concept into something tangible that could be explored and understood.
Other Activities
There were posters describing moons from other planets that complemented the hands-on activities. We also had scaled-down circles showing the relative sizes of different planets and moons. People could use them to make tiny models of them with clay. Colouring sheets with details about various planetary bodies were also provided as an activity.
The visitors also actively discussed questions they had – from the earth’s rotation to timing craters on the Moon to the need for scientific research in India – with the keen volunteers from ICTS.
Before dispersing, the visitors were given stickers with images of the lunar eclipse. The event had 98 attendees – 58 adults and 40 children. Having the event at our campus was a joyful mix of science and community. We look forward to hosting such events in our campus!