The first lot of data sent back by the New Horizons space probe shows Pluto is larger than scientists thought, Nasa has revealed.
As the craft made history earlier today by passing closer to the dwarf planet than ever before, experts answered questions from people on Twitter about the mission.
The team revealed that not only is Pluto bigger than expected, it definitely has polar ice caps.
Nasa scientists working on the nine-year, three billion-mile journey to examine Pluto cheered, shouted and waved flags as the New Horizons probe made its closest ever approach to the dwarf planet.
The craft will now carry out detailed analysis of the composition of Pluto, as well as capturing high-definition images, in what scientists hope will shed light on the make-up of the solar system.
US space probe New Horizons has reached 8,150 miles (13,116km) of the surface of Pluto - the closest-ever approach to the dwarf planet.
Nasa has released the latest image taken by the probe to coincide with the historic flypast.
A new picture showing Pluto in better detail than ever before - including its distinctive heart-shaped spot - has today arrived back on Earth after being beamed billions of miles through space.
The new image came as US space probe New Horizons makes its closest approach to the dwarf planet in the history of space exploration, coming within 7,767 miles (12,500km) of the surface within the next half an hour.
The nine-year, 3.26 billion-mile mission aims to collect data about the composition of Pluto, downgraded from planet to dwarf planet in 2006.
It has also provided better quality images, replacing the blurry shots previously captured by Nasa telescopes.
This picture was taken yesterday evening at 9pm UK time, at around 476,000m (766,000km) from the surface, and posted to Nasa's Instagram page today.
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A rocket exploded two minutes after liftoff from Florida, destroying a cargo ship bound for the International Space Station in the latest in a string of mishaps in supplying the orbiting outpost.
An unmanned Space Exploration Technologies is 208-foot-tall (63-metre) rocket, built and flown by the company known as SpaceX that is owned by technology entrepreneur Elon Musk. It had previously made 18 successful launches since its 2010 debut.
Those included six cargo runs for Nasa under a 15-flight contract worth more than $2 billion.
American space agency Nasa said its SpaceX vehicle " experienced an anomaly on ascent" before breaking up.
Falcon 9 experienced a problem shortly before first stage shutdown. Will provide more info as soon as we review the data.
The vehicle experienced an anomaly on ascent. Team is investigating. Updates to come.
Nasa has said that the SpaceX vehicle which due to carry space station supplies has "broken up" after "something went wrong with the launch".