Oct. 20, 2017 — The Laser Interferometer Gravitational-Wave Observatory (LIGO) has detected gravitational waves from a neutron star-neutron star merger. This event reveals a direct association between the merger and the galaxy where it occurred. Scientists have been trying to show for decades that this has been happening, but this is the first time they’ve been able to prove it. However, what makes this event unique from the previous four gravitational waves detected prior, is that this neutron star-neutron star merger was detected in three different ways.
LIGO detected gravitational waves. The FERMI satellite detected gamma rays, and hours later as the sun set in Chile, the Dark Energy camera saw an optical source (light) from a neutron-neutron star merger. This multi messenger astronomy event was the first detection of its kind in history. The images from the Dark Energy camera were processed using the Dark Energy Survey (DES) data reduction pipelines at NCSA using HTCondor.
“HTCondor has made it possible for us take raw data from a telescope and process and disseminate the results within hours of it the observations occurring,” Professor Robert Gruendl production scientist for DES and senior research scientist at NCSA.
HTCondor is a specialized workload management system for compute-intensive jobs. Unlike simple batch systems, HTCondor has the ability to distribute workloads across many sites. DES is actively running workloads on Blue Waters, Illinois Campus Cluster, and the Open Science Grid at Fermilab. “HTCondor’s central role in the production system is to make data available scientists within hours of being observed,” said Miron Livny.
The National Center for Supercomputing Applications (NCSA) at the University of Illinois at Urbana-Champaign and HTCondor at the University of Wisconsin-Madison Center for High Through Computing(CHTC) have been collaborating on projects for 30 years.
“This collaboration will be a powerful means to develop high-throughput computing (HTC) data processing and analysis capability that is also beginning to address the unique and evolving needs of the LSSTcommunity while advancing the state of the art of HTC,” said Miron Livny, senior researcher in distributed computing at the University of Wisconsin-Madison. “This mutually beneficial partnership will deliver better astronomy science and distributed data intensive computing science,” said Livny. The Condor project also contributed to the TeraGrid project and the GRIDS project, both involving significant NCSA involvement.
Originally known as simply Condor, this system reprocessed radio data from the Baltimore-Illinois-Maryland Association (BIMA) in the late eighties. This collaboration between the Universities of California, Illinois, and Maryland built and operated the BIMA radio telescope array, which was the premier imaging instrument of its time in 1986 at millimeter wavelengths in radio astronomy.
The Dark Energy Survey Data Management (DESDM), led by NCSA, has relied on HTCondor software to enable data processing on the Blue Waters supercomputer for DES. DES is an international, collaborative effort to map hundreds of millions of galaxies, detect thousands of supernovae, and find patterns of cosmic structure in an effort to understand dark matter and the expansion of the Universe.