Mysterious Interstellar Object Captures Scientists’ Attention
A mysterious interstellar object is currently traversing our solar system after a journey spanning billions of years through the vastness of space. This object, known as 3I/ATLAS, was first detected by astronomers on July 1 and is only the third visitor from another star to be identified in our region of space. As it continues its path, 3I/ATLAS will reach its closest point to the sun on October 30, at a distance of 130 million miles (210 million km), before eventually disappearing once again.
Before it vanishes forever, scientists are eager to send a spacecraft to intercept this enigmatic object. Researchers are exploring the possibility of redirecting spacecraft already in orbit around various planets to meet with 3I/ATLAS before it exits the solar system. However, the challenge lies in the object’s speed—over 37 miles per second (60 km/s)—which makes interception extremely difficult.
Scientists hope that by reaching 3I/ATLAS in time, they could gain valuable insights into its origins and potentially answer significant questions about the formation of the galaxy. Some experts, such as Harvard’s Professor Avi Loeb, believe this mission could even help determine whether the object is an alien probe.
Rare Interstellar Visitors
Objects originating from other solar systems are exceedingly rare compared to the thousands of meteors that come from within our own system. Prior to 3I/ATLAS, the only other known interstellar objects were ‘Oumuamua in 2017 and comet Borisov in 2019. This rarity makes the current opportunity to observe 3I/ATLAS as it passes near the sun an exciting moment for scientists globally.
The object has already been observed by large telescopes such as Gemini North in Hawaii and the Very Large Telescope in Chile. Plans are also underway to use the sensitive instruments on the James Webb Space Telescope for a closer look. However, to truly understand what 3I/ATLAS is made of, scientists believe a spacecraft needs to get much closer.
Challenges in Intercepting 3I/ATLAS
The main challenge is that 3I/ATLAS is moving too fast and is too far away for an Earth-based launch to reach in time. In a recent pre-print paper, researchers from Michigan State University calculated that a craft would need to have left Earth at 15 miles per second (24 km/s) on the day the object was spotted to stand a chance of arriving in time.
Instead, researchers propose that space agencies like NASA should consider redirecting spacecraft already in orbit around other planets towards 3I/ATLAS. Professor Loeb suggests using the Juno spacecraft, which is currently gathering data from its orbit around Jupiter. He notes that 3I/ATLAS will pass within 54 million kilometers from Jupiter in mid-March 2026. If Juno can be redirected using its remaining fuel, it might meet 3I/ATLAS around March 14 next year.
If successful, Juno’s sophisticated equipment could provide unprecedented data about this interstellar object. However, not everyone is convinced that Juno has the power or fuel needed to escape its orbit and reach 3I/ATLAS. Some experts argue that Juno does not have enough fuel and its main engine may be malfunctioning.
Other Possible Options
The European Space Agency (ESA) is reportedly considering using its Jupiter Icy Moons Explorer (JUICE), which is currently on its way to the planet. While JUICE might have more fuel than Juno, ESA is still uncertain whether its course could be diverted to align with 3I/ATLAS. Currently, there are no concrete plans to divert JUICE out of its current orbit.
Another option would be to use one of the spacecraft currently orbiting Mars, such as Mars Odyssey or the Mars Reconnaissance Orbiter. According to Atsuhiro Yaginuma and his co-authors from Michigan State University, one of these spacecraft could reach 3I/ATLAS after setting off as late as September. Boosting a Mars orbiter by 10,800 miles per hour (17,400 km/h) could allow one of these probes to reach 3I/ATLAS before it leaves the solar system.
However, it remains unclear whether any of the spacecraft currently orbiting Mars have enough fuel to make the trip. If a craft were able to reach 3I/ATLAS in time, it could mark a significant breakthrough in understanding the galaxy.
Scientific Implications
Dr Marco Fenucci of the European Space Agency’s Near-Earth Objects Coordination Centre noted that while the scientific return would be immense, the mission design would be complex and time-sensitive. Interstellar objects offer a unique opportunity to study the composition of another star system, providing insights into how similar our solar system is to others.
By approaching the object, a spacecraft may be able to analyze dust and ice surrounding 3I/ATLAS and capture high-resolution images. This data could help astronomers understand how solar systems form and how chemicals necessary for life are delivered to habitable worlds.
Amid speculation that 3I/ATLAS may be of alien origin, a visit from one of our probes could help settle this debate. Although the scientific consensus is that 3I/ATLAS is a comet, Professor Loeb maintains that it could be an artificial craft. He argues that objects of this size should only arrive in the solar system once every 10,000 years, and its suspicious path through the solar system adds to the intrigue.
As 3I/ATLAS gets closer to the sun, future observations should reveal more cometary activity if it is indeed a natural object.