Video: New Horizons animation

A crescent Pluto stars in pictures captured just after NASA’s New Horizons spacecraft’s July flyby of the distant dwarf planet, exposing eerie backlit fog banks that scientists say hint at an Earth-like weather cycle.

Now just three weeks from its historic flyby of Pluto, NASA’s New Horizons spacecraft is close enough to detect objects smaller and dimmer than the dwarf planet’s smallest known moon and so far, nothing has been spotted that would pose a threat to the probe as it barrels through the system at more than 30,000 mph, scientists said Tuesday.

New Horizons project manager Glen Fountain, a veteran of nearly 50 years at the Johns Hopkins University Applied Physics Laboratory, told the Pluto probe’s team to live in the moment for Tuesday’s historic flyby, but look out for last-minute snags.