This morning, while most of us were rolling out of bed and getting our morning coffees, we reached a milestone in space exploration. After traveling more than 3 billion miles over the last nine years, a NASA spacecraft finally reached Pluto, the furthest planet from us in the solar system.
Here's the last photo sent back home by the probe at just before 8 a.m. EST this morning, before it stopped communicating with us to focus on gathering data from its fly by of the dwarf planet:
The spacecraft, New Horizons, will spend the next two days observing Pluto and collecting scientific data while flying over its 1,472 mile-wide surface. The recon mission means that we've now been able to send probes to every planet in our solar system.
"We have completed the initial reconnaissance of the Solar System, an endeavor started under President Kennedy more than 50 years ago and continuing to today under President Obama," the mission's chief scientist Alan Stern told BBC News.
New Horizons will send the images back to earth by Wednesday night. It's also flying past Pluto's five moons. You can see its largest and closest moon, Charon, in one of the photos below:
NASA tells us that on Pluto, frozen nitrogen, methane, and carbon monoxide have been found. Charon's surface contains frozen water and ammonia compounds.
Learn more about Pluto from NASA:
In 2006, Pluto actually lost its status as a planet–scientists of the International Astronomical Union decided it's actually too small to be considered a regular planet. But it was re-designated a "dwarf planet," a title that's still controversial but officially used across the board.