Pluto mission: Have a look at the first close-up image

The historic first close-up image of the dwarf planet Pluto has finally reached Earth, beamed back by the New Horizons spacecraft.

It has astounded the scientists at mission control as they begin to study what the image reveals.

The first image represents only a small segment of the whole planet but this fragment has revealed an amazing amount of unexpected details.

They have found no craters as seen in the accompanying image. This means that the planet must be active in some way and able to renew its surface periodically, the scientists said.

The picture shows mountains towering an estimated 11,000 feet. They also found water ice in great abundance close to the surface and as near as they can tell deeper under the surface.

Scientists had long assumed the small distant moons around the outer planets were smooth and with few craters because of the powerful gravity they exert. But Pluto has no such gravity effect so the planet’s surface is being renewed by some other means that remains to be understood.

The remarkable picture was taken 31 hours earlier as the satellite hurtled past the planetoid at 14km per second.

Taken at a height of 12,500km above the planet it shows complex surface features including plains and mountain ranges.

Congratulations have poured into the US National Aeronautics and Space Administration including a message from physicist Stephen Hawking and a tweet from US President Barack Obama.

The satellite is now millions of miles beyond Pluto, and is already streaming back pictures and data to huge radio signal dishes back on Earth. While most public interest focused on our fist look at distant Pluto, New Horizons also carries six instruments that collected data.

It will take all of 16 months for the space probe to download all of the pictures and information taking during the relatively brief flyby. It is a slow process because the satellite transmitter is only 12 watts, barely more than a small night-light. And New Horizons must share time on the big 70 metre dishes with other satellites trying to keep in touch.

The mission to Pluto caps 50 years of space exploration during which satellites completed flybys, went into orbit or actually landed on each of the planets in the solar system.

Some missions remain ongoing including Cassini to Saturn, a collection of orbiters and landers to Mars and Juno to Jupiter.

The Voyager 1 and 2 spacecraft also continue their mission to pass through the limits of our solar system to reach deep space beyond.

New Horizons also remains in service. It will now travel into a region at the edge of the solar system beyond Neptune called the Kuiper Belt.

This is a debris field loaded with material left behind after the planets formed 4.6 billion years ago.