Pluto is cold. Very very cold. Pluto is so far away from the Sun that temperatures can drop down to 33 Kelvin, or -240 Celsius.
You can also look through these books from Amazon.com if you want more information about Pluto.
But the temperatures on Pluto can actually vary. This is because the orbit of Pluto is highly elliptical, ranging from 4.4 billion km to 7.4 billion km away from the Sun. This lowest temperature of -240 C occurs when Pluto is at its furthest. At this point, Pluto is very cold.
When Pluto gets closer to the Sun, it actually warms up to the point that frozen material on the surface of Pluto sublimates and becomes an atmosphere. When the atmosphere does this, it actually causes an anti-greenhouse effect, cooling the planet down. Pluto isn’t as cold as it should be, and astronomers have recently determined that Pluto is 43 kelvins or -230 Celsius.