Where is Sputnik Planitia on Pluto?
Sputnik Planitia is centered at 19.51° north, 178.69° east, in Tombaugh Regio, the bright heart-shaped region on the side of Pluto New Horizons saw up close. The gazetteer counts Pluto's longitudes eastward from 0° to 360°, and so does OrbitStudio on Pluto, so the plain is not split where other maps put the 180° line. In 2015 NASA called it Sputnik Planum; the International Astronomical Union adopted Sputnik Planitia in 2017. On Pluto, plains are named after pioneering space missions and spacecraft, and this one after the first satellite.
How deep is Sputnik Planitia?
About 2 kilometers below Pluto's mean radius, and 2.5 to 3.5 kilometers below the rim of the basin that holds it, in the New Horizons team's measurement. The bright ice forms a pear-shaped oval roughly 1,500 by 900 kilometers, narrower to the south, inside a depression about 2,000 by 1,200 kilometers across, and at its southern tip the ice lies 4 kilometers below the mean radius, among the lowest ground on Pluto. The ice is a mix of nitrogen, methane and carbon monoxide, and it is the flattest of the terrains the team measured.
It is also young. Its surface is divided into slowly churning cells 16 to 48 kilometers across, less than a million years old, which the New Horizons team puts down to slow convection in the ice, and the team puts the crater retention age of the basin's ice at no more than about 10 million years.
What does Sputnik Planitia look like as a 3D print?
A smooth floor in a rough frame. The plain is wider than its entry's box, which frames about 1,040 kilometers round its center, most of the plain. On a model 200 millimeters across the relief in that view comes out at about 1.5 millimeters at true scale and about 3 millimeters at the 2x Pluto models start at, most of it in the rim and in the mountains of the western edge; the ice itself prints flat. At 2x to 3x the heart reads as a shape.
For more relief, frame a smaller piece of the edge: Tenzing Montes or Hillary Montes put the ice beside mountains several kilometers high, and a box a few hundred kilometers across gives several times the relief of the whole plain.
What is OrbitStudio?
OrbitStudio turns real elevation data into 3D-printable models. You pick a region of Pluto on a globe or a flat map, choose a jigsaw puzzle or a solid ornament, and get ready-to-print files with terrain and borders already separated and colored. No CAD, no mesh repair. The heights come from New Horizons' stereo topography, posted at 300 meters per pixel.
Trying it is free and needs no account: pick a region, generate it and turn it around in 3D. Downloading the model — STL files and pre-colored 3MF files for Bambu Studio or OrcaSlicer — takes a Plus or Merchant plan, or one credit from a pass. The generator covers the Moon, Mars, Mercury and Venus too.
Other landmarks
The night sky, too
OrbitStudio Sky, the night-sky tool, turns the sky over any place, on any date from 1900 to 2100, into a 3D-printable star map. Its STL is free.