Pulsars are a kind of neutron star, and they are also a mess of food. Sometimes, when they devour a companion star, they spit out a lot of energy. For the first time, astronomers have captured the moment that caused this violent eruption in fine detail. A new study, presented Monday at the virtual Meeting of the American Astronomical Society, details the extreme eruption of SAX J1808.4-3658, a neutron star about 11,000 light-years from Earth that spins at an unimaginable speed and rotates 401 times per second. However, this is also normal from the perspective of the neutron stars, because these strange cosmic monsters are the most extreme physical phenomena in the universe.
Neutron stars are very dense, and if you put your hands together and fill them with neutron star material, you hold about five Mount Everests because they are so dense that they produce some of the most powerful gravitational fields in the universe. And these extreme physics principles are part of the reason why writers are so fascinated.
Their research focused on “proliferating neutron stars”, neutron stars surrounded by gas and fragmental disks. These types of pulsars are in the same orbit as a “normal” star, such as our sun, and because of their huge gravitational pull, they suck matter from the star over a period of months to years. Eventually, they suck up enough material to heat it up and spiral into the star, creating huge bursts that release energy thousands of times more powerful than the sun.
Goodwin and a team of international co-sponsors used seven different telescopes to observe SAX, including NASA’s Swift X-ray Observatory and the NICER instrument on the International Space Station. Astronomers have seen a growing pulsar transition to an explosive state.
Current theory is that the whole process should take about two to three days, but the team observed a delay of up to 12 days. They believe the delay may be due to the fact that the dust and gas trays around SAX are made up of more helium than most plates. This may delay the outbreak process.
The work, which will be published in the British Astronomical Society’s Monthly Journal, will be available on the preprint server arXiv from Friday.