What would life be like on a planet orbiting a pulsar? Astronomers estimate that the Milky Way galaxy contains an estimated 1 billion neutron stars, of which about 200,000 are pulsars –neutron stars of only 10 to 30 kilometers in diameter with enormous magnetic fields, that accrete matter and regularly burst out large amounts of X-rays and other energetic particles. So far, 3000 pulsars have been studied and only 5 pulsar planets have been found. In 1992, the first exoplanets ever were discovered around pulsar PSR B1257+12.
In 1967, Jocelyn Bell, then a graduate student in astronomy at Cambridge University, noticed a strange signal, a series of sharp pulses that came every 1.3 seconds, in the data of her radio telescope that seemed too fast to be coming from anything like a star. Bell and her advisor Anthony Hewish initially thought they might have detected a signal from an extraterrestrial civilization that they named LGM-1, for “Little Green Men.” (It was later renamed.) It turned out not to be aliens, but rather the discovery of the first pulsar.
Astrophysicists are radically expanding our knowledge of image of pulsars, the ancient remains of exploded stars so dense their gravity warps nearby space-time, using NASA’s Neutron star Interior Composition Explorer (NICER), an X-ray telescope aboard the International Space Station to create the first-ever map of million-degree hot spots on the surface of J0030 in an isolated region of space 1,100 light-years away in the constellation Pisces.
The first-ever observations of merging binary stars stunned the world’s astronomy community, but not quite as stunning as the first-ever signal from extraterrestrial life will be. GW170817 is the name given to the gravitational wave signal seen by the LIGO and Virgo detectors on 17 August 2017. Lasting for about 100 seconds, the signal was produced by the merger of the two neutron stars. The observation was then confirmed – the first time this has happened for gravitational waves – by observations with light waves.