Vesta meteorite on show at Ulster Museum
Nasa has spent half a billion dollars sending its Dawn probe 188 million km (117 million miles) from Earth to study the asteroid Vesta.
It is the second most massive body in the asteroid belt between Mars and Jupiter and the brightest in the solar system.
Vesta has been rolling through deep space since the Sun, Earth and other planets were born, 4.5 billion years ago.
And there's a piece of it in Belfast.
Around one billion years ago, something substantial crashed into Vesta, leaving a 460km crater on the face of the 530km-wide proto-planet.
Shrapnel from that impact exploded out into space.
After a billion years in space, one fragment finally crashed to earth in Western Australia in 1960.
The unimaginably ancient visitor from that far away worldlet is now on show for free at the Ulster Museum.
Although the piece went on display a few years ago, the museum is delighted that, thanks to the high-profile Nasa mission, they have a chunk of an asteroid that is rapidly reaching celebrity status.
Previously it was just a small part of their meteorite display. Now it's set to be a star.
Launched four years ago, the Dawn probe entered into orbit around Vesta on 17 July, and will spend 12 months studying the rock before moving on to the biggest object in the asteroid belt - the dwarf planet Ceres.
Both objects should have something to say about the earliest days of the Solar System. Scientists often describe asteroids as the rubble that was left over after the planets proper had formed.
"It cost half a billion dollars to send Dawn to Vesta", says Mike Simms of the Ulster Museum.
"It took about three years to get there. To get to the Ulster Museum and actually see a piece of Vesta takes a fraction of the time and is free except, of course, for the bus fare."
Although initially orbiting the rock at several thousand km, Dawn will move closer over time - perhaps to within 200km if navigators are confident there is no risk to the spacecraft.
Once it has completed its work at Vesta, the probe will move on to the even bigger rock, Ceres. With a diameter of roughly 950km, this world has a much more rounded shape and is classed as a "dwarf planet", the same designation now ascribed to Pluto.
Alas, to the best of their knowledge the Ulster Museum has no bits of Ceres.