• A comet from outside the solar system is approaching Earth on Friday
• Last chance to observe it before it permanently returns to interstellar space

A rare comet is approaching Earth this week, notable for originating from interstellar space—that is, from outside the solar system.

The comet was discovered last summer and is named 3I/‘Atlas’, and it is expected to pass at a distance of 167 million miles (269 million kilometers) from Earth on Friday, its closest point during its major journey within the solar system.

NASA continues to direct its space telescopes to monitor the icy comet, whose size is estimated between 440 meters and 5.6 kilometers, while the current time is considered ideal for observation through ground-based telescopes before it gradually disappears.

The comet is expected to come closer than Jupiter in March, passing at a distance of 33 million miles (53 million kilometers).

It is projected to reach interstellar space by the mid-2030s and will not return, according to Paul Chodas, director of NASA’s Center for Near-Earth Object Studies.

3I/‘Atlas’ is the third known object from outside the solar system to pass through it, while local comets, such as Comet Halley, originate from the icy outskirts of the solar system.