NASA probe MAVEN goes dark after close encounter with interstellar visitor 3I/ATLAS

NASA's Mars orbiter MAVEN has gone dark, nearly two weeks after its close encounter with the interstellar object 3I/ATLAS. The agency said the spacecraft stopped transmitting on December 4 while it was observing the visitor, which NASA has identified as a comet. 3I/ATLAS is on a trajectory that will bring it closer to Earth this month, and observers around the world are tracking the object as part of broad efforts to study its nature.

MAVEN, which has orbited Mars since 2014 and has served as a communications relay for surface missions, moved behind Mars while monitoring the interstellar visitor, then briefly reemerged into view of Earth before losing contact. NASA said the probe began rotating unusually as it reappeared and has not yet resumed normal transmissions. The agency added that whatever happened to MAVEN on the far side of Mars may have altered its orbit around Mars, though officials stressed that they cannot confirm the extent of any change without telemetry from the spacecraft. In the meantime, NASA is relying on tracking data and ground observations to piece together what occurred.

Details about the event come as 3I/ATLAS nears a notable milestone: on December 19 it is expected to pass within about 170 million miles of Earth, its closest approach to our planet on its probe through the solar system. While MAVEN was offline, officials with NASA and the European Space Agency have stressed that the blackout is not believed to be related to the interstellar object itself, though the timing has fueled public speculation.

Prior to the outage, MAVEN captured photos of 3I/ATLAS at a distance of about 18 million miles in October, a sequence that drew scrutiny for its apparent lack of detail. NASA has said the quality of those images does not affect the scientific conclusions being drawn about the object, but critics argued that the imagery raised questions about data handling and transparency. Avi Loeb, a Harvard professor and head of the Galileo Project, has noted that NASA released some imagery from the October pass and has continued to advocate for transparent data sharing. He also has highlighted what he describes as anomalies associated with 3I/ATLAS, including unusual features such as an anti-tail and rapid color changes, which he says are hard to reconcile with a conventional comet.

The ongoing analysis is happening in a broader context of international tracking efforts. More than 23 nations in Europe are actively monitoring 3I/ATLAS as part of what organizers describe as the largest planetary defense drill in history. While some observers remain skeptical, NASA and the European Space Agency have repeatedly stated that 3I/ATLAS is best described as a comet from a distant solar system with a distinctive chemical makeup.

As researchers await MAVEN's return to communications, astronomers caution that confirming any changes to the spacecraft's orbit will require direct telemetry. The incident underscores the challenges of coordinating long-running spacecraft operations while tracking fast-moving interstellar visitors. Scientists say the data gathered from MAVEN and from ground-based observations in the coming days could help clarify whether the blackout is an isolated anomaly or part of a broader effect on the spacecraft’s trajectory. In the meantime, the public is encouraged to monitor 3I/ATLAS as it becomes visible to amateur telescopes in the weeks surrounding its December close approach to Earth, with observers urged to consult local skywatching resources for optimal viewing conditions.