This photo provided by ESA shows an all-sky view of stars in our Galaxy, the Milky Way and neighbouring galaxies, based on the first year of observations from ESA's Gaia satellite. Photo / AP
This photo provided by ESA shows an all-sky view of stars in our Galaxy, the Milky Way and neighbouring galaxies, based on the first year of observations from ESA's Gaia satellite. Photo / AP
The most detailed map of the night sky ever produced, which pinpoints the locations of more than one billion stars, was released today.
The image is the result of 14 months of sky scanning by the European Space Agency's Gaia satellite which carries a one-billion pixel camera designed by British engineers.
Scientists said the map was one of the most significant produced in modern astronomy since Galileo drew the first star chart of Orion in the early 17th century.
Antonella Vallenari, of Gaia Data Processing and Analysis Consortium, Observatory of Padua, said: "In 1610, Galileo took a prototype of a telescope which had been built just for defence purposes and pointed it to the sky. To his great astonishment he discovered that the Milky Way is full of stars in all directions," she said.
"This is what we think of as the birth of modern astronomy. Since that moment people have begun to look at the sky with different eyes. Galileo produced a map showing the Orion cluster of stars which was a revolution and now this is a new revolution.
"Gaia is going to provide not only information about the stars in the sky but also about the motion of the stars and information about how the stars formed."
Gaia, which is around 10m-wide with its solar panels outstreteched, sits in an observing location 11.5 million km from Earth, from where it can slowly spin and scan the sky. The satellite was launched 1000 days ago and started its scientific work in July 2014.
It's array of powerful cameras have been designed by Chelmsford-based technology specialists e2v and is are powerful they can measure the diameter of a human hair at a distance of 1000km.
The cameras work by picking up light and turning it into an electric signal which is then beamed to Earth. The most powerful instrument on Nasa's Hubble space telescope incorporates two such cameras but Gaia has 106 meaning it can pick up far more data than ever before.
"The beautiful map we are publishing today shows the density of stars measured by Gaia across the entire sky, and confirms that it collected superb data during its first year of operations," said Timo Prusti, Gaia project scientist at ESA.
The Milky Way is a spiral galaxy, with most of its stars residing in a disc about 100,000 light-years across and about 1000 light-years thick.
This structure is visible in the sky as the Galactic Plane - the brightest portion of this image -which runs horizontally and is especially bright at the centre.
Brighter regions on the map indicate denser concentrations of stars, while darker regions correspond to patches of the sky where fewer stars are observed.
A man walks in front of a slide show depicting a representation of the ESA Gaia Project, at the ESA centre near Madrid, Spain. Photo / AP
Darker regions across the Galactic Plane correspond to dense clouds of interstellar gas and dust that absorb starlight along the line of sight.
The two bright objects in the lower right of the image are the Large and Small Magellanic Clouds, two dwarf galaxies orbiting the Milky Way.
Other nearby galaxies are also visible, most notably Andromeda, the largest galactic neighbour to the Milky Way, in the lower left of the image. Below Andromeda is its satellite, the Triangulum galaxy.
A number of features and darker stripes are not of astronomical origin but rather reflect Gaia's scanning procedure and will gradually disappear as more information is gathered during the five-year mission.
"Gaia is at the forefront of astrometry, charting the sky at precisions that have never been achieved before," said Alvaro Giménez, ESA's Director of Science.
"Today's release gives us a first impression of the extraordinary data that await us and that will revolutionise our understanding of how stars are distributed and move across our Galaxy."
The mission is also hoping to map thousands of new asteroids and comets in the Solar System and seven thousand new planets in neighbouring star systems. It is also hunting for exploding stars, called supernovae and distant galaxies.
Gaia will observe one billion stars about 70 times each over five years. That's an average of 40 million observations a day. However one billion stars is one per cent of all the stars in the Milky Way.
