It’s comet 2I/Borisov’s time to shine. The interstellar comet has been steadily getting brighter since it was first spotted in September, and now it’s reaching its brightest moments as it passes close to the sun and Earth.

We know that Borisov comes from another stellar system because of its trajectory: rather than orbiting the sun like comets from our own solar system, it is simply passing through. It came in from above the plane on which the planets orbit and is now passing between the orbits of Mars and Jupiter.

It makes …