Nasa spacecraft speeds past Pluto

Nasa's New Horizons spacecraft has made the first visit to Pluto, speeding past at 14km per second.
Earlier, the space agency released the most detailed picture yet as it hurtled towards the dwarf planet on Tuesday.
The probe was set to grab more pictures and other science data on the object, as it passed 12,500km from the surface.
Controllers got a last health status report, before the robotic craft turned its antenna away from the Earth to concentrate on its target.
Only when New Horizons has its trove of images safely in its onboard memory will it call home again.
This is not expected to happen until just after midnight (GMT) into Wednesday.
It means there will be a long, anxious wait for everyone connected with the mission, as they hold out for a signal that will be coming from almost five billion km away.
New Horizons' flyby of 2,370km-wide Pluto is a key moment in the history of space exploration.
"We have completed the initial reconnaissance of the Solar System, an endeavour started under President Kennedy more than 50 years ago and continuing to today under President Obama," said the mission's chief scientist Alan Stern.
"It's really historic what the US has done, and the New Horizons team is really proud to have been able to run that anchor leg and make this accomplishment."
It marks the fact that every body in that system - from Mercury through to Pluto - will have been visited at least once by a space probe.
John Grunsfeld, Nasa's science chief, added that the mission was "true exploration".
New Horizons has been returning a steady stream of information on approach to the dwarf world in recent days, but this will be as nothing compared to the huge number of observations it will have acquired when passing just 12,500km from the surface.
This was timed to occur at 11:50 GMT (12:50 BST).
The probe will investigate not only Pluto but also its five moons: Charon, Styx, Nix, Kerberos and Hydra.
To achieve that, it must perform a furious set of manoeuvres as it points every which way in the sky to get the images and other types of data it needs.
"I can't wait to get into the data and really start making sense of it. Right now, we're just standing under the waterfall and enjoying it," New Horizons' principal investigator, Alan Stern, told BBC News.