page_title: PSR B1620−26
section_title: Planetary system
hierarchical_section_title: PSR B1620−26 / Planetary system
caption_attribution_description: English: Evolution of PSR B1620-26.
context_page_description: PSR B1620−26 is a binary star system located at a distance of 3,800 parsecs in the globular cluster of Messier 4 in the constellation of Scorpius. The system is composed of a pulsar and a white dwarf star or PSR B1620−26 B. As of 2000, the system is also confirmed to have an exoplanet orbiting the two stars.
context_section_description: PSR B1620−26 b was originally detected through the Doppler shifts its orbit induces on signals from the star it orbits (in this case, changes in the apparent pulsation period of the pulsar).
  In the early 1990s, a group of astronomers led by Donald Backer, studying what they thought was a binary pulsar, determined that a third object was needed to explain the observed Doppler shifts. Within a few years, the gravitational effects of the planet on the orbit of the pulsar and white dwarf had been measured, giving an estimate of the mass of the third object that was too small for it to be a star. The conclusion that the third object was a planet was announced by Stephen Thorsett and his collaborators in 1993.
caption: The evolution of the PSR B1620−26 system
exif: {}