When a government conducts a census, they send someone door to door and count people. In space, if you want to count the stars, it gets complicated. Fast.

Unlikely as it sounds, the so-called "stellar census" is underway--an ambitious project of the European Space Agency (ESA) that could help resolve mysteries about the origin and evolution of the galaxy.

The humble goal of the project? To draw the largest and most precise three-dimensional map ever of our beloved home, the Milky Way. When completed, this atlas of 1 billion stars will actually represent a mere 1 percent of the Milky Way's celestial payload; nevertheless, it will go a long way toward helping us understand where we came from in the deepest and most profound way imaginable. 

THE MISSION. Launched in December 2013, Gaia is an ambitious mission to say the least. By doing this exhaustive 3D mapping, scientists could in the process reveal new details about the composition, formation and evolution of the galaxy. Thanks to new breakthroughs in science, Gaia will provide unprecedented positional and radial velocity measurements that can reach new heights in terms of accuracy.

gaia maps the stars of the milky way

THE SPACECRAFT. At the heart of the five-year mission is the 2,000 kg, 10-meter-wide Gaia spacecraft, which lives to measure not only stars but also planets, comets, asteroids and quasars. Among Gaia's “passengers” are two telescopes and a billion-pixel camera. As the spacecraft slowly orbits around the sun, her telescopes perform an uninterrupted scan of the sky.

While Gaia slowly spins over a period of six hours, the telescopes simultaneously observe two rectangular patches of sky that are separated by an angle of 106.5 degrees. Each telescope has a large, rectangular primary mirror. Three curved mirrors and three flat mirrors focus and repeatedly fold the light over a total distance of 35m before reaching the focal plane where the camera is located.

 
The spacecraft will monitor each of its target objects about 70 times over a five-year period to study the precise position and motion of each target. The highly precise calculations being done based on that data represent a veritable revolution in astrophysics. To put it into perspective, ESA scientists have compared Gaia's challenge to attempting to measure the diameter of a human hair from 1,000 kilometers away.

gaia's first sky map, annotated

THE LENOVO PART. When you’re charting more than a billion stars, accuracy is paramount. That’s where Lenovo comes in. The Gaia project requires advanced technology that can help manage vast volumes of information without making errors. That’s why the ESA recently renewed its contract with us, extending a five-year relationship through which their team of scientists uses Lenovo NeXtScale technology to process those large volumes of data.

Lenovo has been working with the ESA's European Space Astronomy Centre to facilitate the processing of Gaia’s data since 2011. Once the mission is complete, the final file is expected to represent more than a petabyte, or a million gigabytes, of data. Put another way, that’s about 200,000 DVDs worth of data.

a sky scan from the gaia spacecraft

Our collaboration with the ESA is the latest evidence of Lenovo’s commitment and ambition in the High Performance Computing market. In 2015 we opened a Global HPC Innovation Centre in Stuttgart as a base to permanently foster R&D and application benchmarking. Lenovo also joined the European Technology Platform for High-Performance Computing, a think tank with the objective of taking an active role in defining research priorities and action to help the European Commission define and excel in HPC.

THE HOPE. The ESA released its first batch of data from the mission in September 2016, at which time mission manager Fred Jansen said he was happy with the quality and precision of the 500 billion data measurements Gaia had already collected. That initial data set has already been distributed within the scientific community for analysis.

Up next: delivery of the full atlas of 1 billion stars, which is expected to happen in April 2018. The scientific community will await this moment with bated breath.

They say you can’t know where you’re going until you understand where you came from. For us—the inhabitants of the Milky Way—it’s electrifying to consider that we could soon know more about our origins and, in the process, gain better insight as to where we’re all headed.

 

Gavin O'Hara is Lenovo's Global Social Media Publisher. All photos courtesy ESA. (Thanks!)