the Science

~ four main areas we study ~

GW151226: Observation of Gravitational Waves from a 22-Solar-Mass Binary Black Hole Coalescence

We congratulate the LIGO Scientific Collaboration and the Virgo Collaboration for their second detection of gravitational waves. The new waves, called GW151226, were also emitted by two colliding black holes; however, these black holes had significantly lower masses than the binary that emitted the first gravitational waves LIGO observed, called GW150914. Unlike GW150914, at least one of the two black holes was definitely spinning! The new system generated many more gravitational wave cycles within the LIGO band (about 55). Please visit for more details. A visualization of GW151226 can be found on the SXS YouTube channel.

GW150914: LIGO detects gravitational waves

On 14 September 2015 at 4:50:45 AM Eastern standard time, LIGO detected its first gravitational waves.  The waves descended on Earth from the southern hemisphere, passed through the Earth, and emerged at the Earth's surface first at the LIGO interferometer in Livingston, Louisiana, and then, 7 milliseconds later, at the LIGO interferometer in Hanford, Washington.  For more information, please visit our dedicated page covering this great discovery.

Explore the Science of SXS


Come, you lost Atoms, to your Centre draw,
And be the Eternal Mirror that you saw:
Rays that have wander'd into Darkness wide,
Return and back into your Sun subside.

From Farid al-Din Attar's twelfth-century masterpiece
The Conference of the Birds

About SXS

The SXS project is a collaborative research effort involving multiple institutions. Our goal is the simulation of black holes and other extreme spacetimes to gain a better understanding of Relativity, and the physics of exotic objects in the distant cosmos.

The SXS project is supported by Canada Research Chairs, CFI, CIfAR, Compute Canada, Max Planck Society, NASA, NSERC, the NSF, Ontario MEDI, the Sherman Fairchild Foundation, and XSEDE.