How ESA’s missions are observing comet 3I/ATLAS – and why it matters
Have you ever wondered what happens when a mysterious comet whizzes past Mars? The European Space Agency (ESA) had a rare opportunity at just such a moment – and it didn’t miss it. With two missions, ExoMars Trace Gas Orbiter and Mars Express, their space probes turned their gaze toward the celestial wanderer named 3I/ATLAS.
But why is this encounter so important? And what exactly did scientists want to learn?
What is comet 3I/ATLAS?
Comet 3I/ATLAS is among the interstellar visitors. This means it does not originate from our solar system but has come from other corners of the galaxy! To date, we have encountered such comets only twice – perhaps you remember the famous ‘Oumuamua. Comet ATLAS is the third confirmed interstellar object to visit us.
What’s even more exciting: this is the first time an interstellar comet is so close to the red planet and simultaneously accessible for observation from a spacecraft in orbit around Mars! Bravo ESA!
Where is this comet now and where is it going?
Comet 3I/ATLAS is just about to bid farewell to the Solar System. At the beginning of 2024, it zipped past the Sun and is now flying back into interstellar space. Its journey is so swift that it hasn’t captured any orbit around the Sun, which is further proof of its “foreignness.”
Imagine: like a tourist, it quickly visits a planet, looks around, maybe takes a selfie – and zooms off toward mysterious stars.
Why is this comet different?
Although it has a tail like many “native” comets, its composition hides elements that we rarely see on Earth. Scientists believe that this data could reveal how star systems form – and what else is out there, beyond our Solar System.
How did the Mars Express and ExoMars missions observe it?
Although these two missions are designed to observe Mars, their view is not limited to just that. At the right moment, they can also turn their instruments toward space. And that’s exactly what they did!
- ExoMars Trace Gas Orbiter (TGO): Its mission is to search for gases in Mars’ atmosphere, primarily traces of methane – a gas that could indicate the presence of life. But this time, it directed its sharp sensors toward comet 3I/ATLAS and analyzed its light.
- Mars Express: The older of the two missions, it has been operational since 2003. It also had the opportunity for stunning observations of the comet and helped gather valuable visual data.
By combining data from both probes, scientists were able to create a more comprehensive picture of what the comet emits and what it is made of.
Was the observation challenging?
Extremely! Imagine having to observe a small, fast-moving object millions of kilometers away from another planet. It’s like watching a firefly fly past another hill from your terrace – while you still have your binoculars aimed at the moon.
The navigational and timing challenges were significant, but ESA’s scientists managed to overcome them.
What have we learned from this encounter?
Although the data is still under analysis, one very interesting thing is clear: the chemical composition of comet 3I/ATLAS is different from most comets that are native to our system. Compounds have been detected that are typically not found in local comets.
This leads us to the question: Are all star systems really that different from one another? If confirmed, this means that each such comet carries its own story – a different ‘DNA’ of its home galaxy.
Why does this matter for humanity?
Humans have always looked to the stars with questions. Where do we come from? Are we alone? How did it all begin? And each such comet can serve us with crumbs of answers.
Observing comet 3I/ATLAS is not just scientific curiosity. It is a window into other worlds. Like finding a message from another planet in a bottle.
What’s next?
ESA will continue to monitor the comet as long as it is visible. The analyses that will follow will aid in preparing future missions that might even intercept such comets beyond our system. Believe it or not, some scientists are already planning how to intercept and collect samples from such visitors in the future.
And who knows, maybe one day we will actually invite some “space tourist” for coffee. 🤔
Conclusion
Comet 3I/ATLAS is yet another reminder that the universe is alive and full of surprises. Observations from missions like ExoMars and Mars Express help us understand our cosmic context. Even if sometimes all we need is a good telescope – and a lot of curiosity.
If you want to follow more such stories from space, keep an eye on ESA’s news – and of course, our blog! 🚀
