In 2002, NASA‘s Chandra X-ray Observatory and the Hubble Space Telescope captured data for this composite image of the Crab Pulsar, a rapidly rotating neutron star the size of Manhattan. The pulsar is the brightest spot in the center of the Crab Nebula shown here. From November 2005 until August 2006, using a set of telescopes called LIGO and the radio telescope at Jodrell Bank in England, scientists again looked at the Crab Pulsar. The LIGO science team searched for any emission of gravitational waves — ripples in the fabric of space and time — and to see if the waves were in sync with the pulsar’s radio emissions. No gravitational waves were detected.

Despite the null result, scientists conclude that less than 4 percent of the Crab’s energy is lost due to gravity waves. The team based the findings on the radio data and the current sensitivity limits of the LIGO detectors. The report was submitted to Astrophysical Journal Letters and posted online.