Chris Korinetz, age 10, of Winnipeg, Manitoba, Canada, for his question:

HOW FAR IS PLUTO FROM THE SUN?

Pluto is the most distant planet from the sun. Pluto and Neptune are the only planets that cannot be seen from earth without a telescope.

The planet Pluto is about 39 times as far from the sun as the earth is. The distance between the sun and Pluto is 3.675 billion miles.

Pluto travels around the sun once about every 248 years, compared to once a year for earth. It has an oval¬shaped orbit that at times brings it closer to the sun than Neptune, the second farthest planet.

Astronomers don't know too much about Pluto's size or surface condition because of its distance from earth. They estimate that it is about half the size of earth and has temperatures as low as minus 360 degrees Fahrenheit. It is doubtful that there's any form of life.  The following are recent statistics on Pluto.

 Pluto Statistics (minor planet)
Planetary Symbol: Name in Roman/Greek Mythology: Pluto / Hades
Diameter: 2,390 km (1,485 miles)
[0.187 x Earth's] Orbital Semi-major Axis: (average distance from Sun) 39.48 AU
(Earth = 1 AU)
Mass: 12.5 x 1021 kilograms (0.0021 x Earth's)
Orbital Eccentricity: 0.2488
Density: 1,750 kg/m3 (0.317 x Earth's)
Maximum Distance from Sun: 49.31 AU ( 7.376 billion km or 4.583 billion miles )
Surface Gravity: 0.58 m/s2 (0.06 x Earth's)
Minimum Distance from Sun: 29.66 AU ( 4.437 billion km or 2.757 billion miles )
Surface Temperature: 40 to 50 K ( -233° to -223° C or -387° to -369° F )
Minimum Distance from Earth: 28.6 AU ( 4.28 billion km or 2.66 billion miles )
Tilt of Axis: 123o Orbital Inclination: (tilt of orbit plane) 17.16°
Rotation Period about Axis:(length of Pluto's day) 6.387 days (retrograde)
Revolution Period about the Sun: (length of Pluto's year) 248 years
Satellites: 3 known