We’ve already had a cow, a koala, a camel, and a Tasmanian devil. And now we also have a bird, even from outside our galaxy. A team of astronomers led by Dutch researchers has discovered a blue flash that does not occur inside the star-forming region as usual, but even outside the galaxy. They resorted to the “Fink” phenomenon (Finch) in line with previous blue flashes such as the cow, koala, camel and Tasmanian devil. They will soon publish their findings MNRAS messages. There is already one Preprint.
the website From Sron (Netherlands Institute for Space Research) avoids detection.
In 2018, astronomers witnessed an intense explosion that was ten to one hundred times brighter than the average supernova. This eruption has been named AT2018cow, nicknamed “The Cow.” This was the first example of bright fast blue optical phenomena (Luminous fast blue optical transients Also known as LFBOTs). To date, only a few of these remarkable events have been recorded. Each of them was named after an animal, inspired by the last letters of their astronomical designation.
The quick, bright blue flashes are only visible for a few days. This is in contrast to supernovae, which last for weeks or months. It’s not clear what causes these flashes, and the latest blue flash raises more questions. Because unlike the previous blue flashes, the bird is not in the galaxy, but outside it. De Vinck is located between a spiral galaxy and a satellite galaxy.
A rare type of supernova
Until now, the blue flashes were thought to be a rare type of supernova. But supernovae are formed by large stars that live only a short time and do not have time to separate from the galaxy in which they were formed.
Because flashes appear quickly and disappear quickly, astronomers search for them with telescopes that continuously monitor large areas of the sky. The bird was discovered by the Zwicky Transient Facility, which maps the entire northern sky every two days. Once the bird was discovered, the researchers began a series of pre-planned observations. They looked using the Gemini South Telescope, the Hubble Space Telescope, the Chandra Space Telescope, and the Very Large Array.
To explain the bird’s unusual location, researchers believe it may have been the result of the explosion of an extremely fast-moving star. An alternative hypothesis is that it relates to two neutron stars that have been moving toward each other in increasingly tight spirals for billions of years and colliding with each other.
In the future, astronomers hope to discover more blue flashes so that they can clarify this phenomenon. They pinned their hopes, among other things, on the Vera C. Rubin Observatory under construction in Chile. This telescope will scan the entire southern sky every few nights.
AT2023fhn (The Sparrow): A bright, fast, blue optical transient at a great distance from its host galaxy. via: AA Chrimes, PG Jonker et al., accepted for publication in MNRAS Letters. [preprint]