According to The Scotsman,
How is that possible?
I guess because it’s so far from the sun.
Ain’t possible, unless Sedna has magical powers or something. I’m guessing it’s a typo.
Ah ha!
Space.com says, “Sedna’s surface temperature is about minus 400 degrees Fahrenheit (-240 Celsius), the coldest known place in the solar system.”
That explains it. Someone got their units mixed up.
So far from the sun it’s colder than absolute zero?
I think not. 
Just think, the teams of both Voyager and Pioneer spacecraft has ventured out into space even farther than this new planet is. So, as a brain teaser, try and imagine how cold these spacecraft are right now and how they STILL manage to send back faint, but present signals back to earth.
Do’h! It did seem like the question was too simple… Didn’t look at the units.
My god, that’s a horrible typo. Thanks for a better article Friedo.