An image captured by the Hubble Space Telescope portrays the supernova remnants cataloged as DEM L 190 or LMC N49 or by other designations observed in the Large Magellanic Cloud. The debris produced by the explosion of a massive star formed what appear from Earth as delicate colored filaments. Those materials projected into interstellar space could end up in other stellar systems, perhaps even in protoplanetary disks which will be enriched by the elements generated by the progenitor star and by the supernova.
About 160,000 light-years from Earth, the Large Magellanic Cloud is one of the Milky Way’s dwarf satellite galaxies. Inside it, a massive star exploded, a very common event that leaves behind remnants that slowly scatter into interstellar space. For millennia, the debris create colorful and spectacular shapes.
At the center of DEM L 190 remains the collapsed core of the progenitor star, which in this case is in the form of a neutron star that spins making a rotation about every eight seconds. Already in the past, astronomers detected traces of an extremely intense magnetic field which places it in the magnetar category.
The supernova remnants DEM L 190 have already been studied with various instruments because they also emit X-rays and gamma rays which were detected by NASA’s Chandra Observatory among others. It’s a so-called soft gamma ray repeater (SGR), a source of gamma rays repeated at irregular intervals. Observations at optical frequencies and at ultraviolet frequencies detectable by the Hubble Space Telescope remain useful to study the debris.
One of the peculiarities of supernova remnants DEM L 190 is their asymmetry. Normally, the debris expansion makes it appear more or less circular in visible light. In this case, the expansion is happening in a region with densities that vary significantly in various directions. Often, in interstellar space, there’s so little gas that we consider it empty but there are areas with clouds of gas and dust or which for other reasons have a higher-than-average material density. When the density is sufficient to generate friction, it slows the expansion of supernova remnants but only in certain directions, making them asymmetrical.
The Hubble Space Telescope was already used years ago to study the supernova remnants DEM L 190 and the first images were published in 2003. These are images captured by the Wide Field Planetary Camera 2 (WFPC2) instrument, later replaced by the more advanced Wide Field Camera 3. Old images continue to be useful and those of DEM L 190 were reprocessed by adding new data and using more advanced algorithms that were improved over time. The result is an enhanced image that offers new details of DEM L 190 that can be useful to study what happens in the millennia after a supernova.
