World gets close look at photographs of dwarf planet Pluto

The world will get its closest look yet

at dwarf planet Pluto today when pictures from the US New Horizons space probe begin to reach Earth.

Snaps from the best holiday ever would not be as anxiously awaited as these images arriving from five billion kilometres away.

The US National Aeronautics and Space Administration (Nasa) will begin to release these close-ups at about 8pm Irish time. By then the New Horizons spacecraft will have left the planet 1.6 million kilometres behind as it continues its journey into a mysterious region of our solar system called the Kuiper Belt.

New Horizons, the fastest spacecraft ever launched, shot past Pluto at nearly 50,000 km/h yesterday taking pictures and collecting scientific data. During the flyby, the first ever close encounter with Pluto, the probe passed within 12,500km of the dwarf planet.

The public and media are fixated on seeing pictures of Pluto, images that will tell us a great deal about the surface.

However, the New Horizons mission is about much more than pictures. Aside from its powerful telescope, the probe carries six experiments that captured a wealth of information during yesterday's flyby of Pluto.

One takes ultraviolet images and another produces true colour images of the surface. There are particle and dust detectors, an instrument that measures solar wind and a radio experiment which will tell scientists about the planetoid’s atmosphere.

Then there is the mission to fly deeper into the Kuiper Belt, the region beyond planet Neptune where Pluto and its moons lie. This large debris field is full of bodies left over from when the solar system formed.

The mission plan is for New Horizon to visit at least one of these objects as it continues deeper into space.

Planners have identified three possibles, but are unsure whether they will be smaller versions of Pluto or made of something else. The target Kuiper Belt bodies range in size from 20km to 55km across, much smaller than Pluto’s 2,328km diameter.

So New Horizons is doing much more than taking snaps; it is capturing a wealth of data that will take scientists years to analyse to help understand Pluto.

Pluto was discovered in 1930 but was renamed a dwarf planet in 2006, considered too small to be a full planet.