NASA's New Horizons spacecraft

NASA's New Horizons spacecraft makes closest approach to Pluto.

Horizons spacecraft made its close fly-by encounter with Pluto after a nine-year journey of more than 5 billion kilometres.

The probe whizzed by the dwarf planet at 9:49pm (AEST) and will beam never before seen photos of Pluto back to Earth which will take approximately four hours.

NASA expects to receive a signal from the spacecraft later this evening to find out whether or not the spacecraft survived the encounter.

Pluto comes into focus

NASA's New Horizons will replace distant images of Pluto with new ones that should allow us to see objects about the size of a 50-metre swimming pool.

Experts said there was a one in 10,000 chance that the baby grand piano-sized spacecraft could collide with debris in the region beyond Neptune, known as the Kuiper Belt.

New Horizon's photos will replace the only tiny pixelated images of Pluto we have had prior to now, and reveal specifics of Pluto previously only subject to speculation.

"This is truly a hallmark in human history," said NASA's head of the science mission directorate, John Grunsfeld.

Original found her:http://www.abc.net.au/news