So. Many. Things.
Short answer: Because we changed the definition of the word “planet” to better fit its meaning.
Even though I helped demote it
Scientists aren't just jerking you around—this is about something more than your childhood nostalgia
An interview with Keri Bean, NASA engineer and R2D2's best friend
It has to do with a surprisingly hazy atmosphere.
The heavy heart may have tipped the world over
We're under a time crunch.
The Dawn spacecraft arrives at Ceres this March, and it could be the most surprising space mission in decades
Short answer: It depends who you ask
The anniversary of the Viking landing
What's on the horizon for the New Horizons spacecraft
The little white dot is only going to get bigger
This year's missions to the outer solar system are set to shake up the planetary family tree
New Horizons scientist Leslie Young discusses what to expect from the flyby on Tuesday, and the 28-year wait leading up to it
The latest and greatest images from the New Horizons mission
With 'Star Trek' and Pluto stamps, its time to start mailing things again
That's three moons down, two to go
And he thinks the upcoming flyby will prove it
New Horizons spacecraft reveals the dwarf planet is slightly larger, has polar ice cap, and more
NASA releases a breathtaking close-up right before New Horizons flyby
Scientists are hot on the trail of our solar system's 9th planet
New false color images reveal surprising geologic details