
This image, made from several photos, shows a comet moving across the night sky above the International Gemini Observatory on Cerro Pachon, near La Serena, Chile. AP
A comet from outside our solar system will pass near Mars this Friday. Known as 3I/Atlas, this comet is travelling at an incredible speed of 193,000 miles per hour. It will come within 18 million miles of Mars, marking its closest point to the red planet on its journey through the inner solar system.
Spacecraft Ready to Watch
Two satellites from the European Space Agency (ESA) orbiting Mars have already turned their cameras toward the comet. NASA’s rovers and satellites on and around Mars are also ready to join the observations. This will help scientists study the comet up close as it moves through space.
A Rare Visitor
3I/Atlas is only the third known object from outside our solar system to pass this close to us. The comet was first spotted in July and has been carefully tracked ever since. Experts say it does not pose any danger to Earth or the planets nearby.
Next Stops for the Comet
After passing Mars, the comet will get closest to the Sun at the end of October. In November, ESA’s Juice spacecraft, which is on its way to Jupiter and its icy moons, will continue to observe 3I/Atlas as it travels further.
The comet will come closest to Earth in December, when it will pass about 167 million miles away. Scientists will use this chance to learn more about its makeup and origin.
What We Know About 3I/Atlas
NASA and the Hubble Space Telescope have measured the size of the comet’s nucleus, which is the solid core at its centre. Estimates say it is no larger than 3.5 miles across. Some data suggests it could be as small as 1,444 feet, or 440 metres.
This small but fast visitor gives scientists a rare chance to study objects from beyond our solar system. Understanding comets like 3I/Atlas could teach us more about how stars and planets form.

