NASA’s Chandra Unveils Mysterious X-Ray Objects

NASA's Chandra X-ray Observatory has discovered a new class of mysterious objects that emit unusually low-energy X-rays alongside intense ultraviolet radiation, according to a study published in Nature Astronomy. These "hypersoft X-ray sources" were found in six different galaxies using publicly available data from the Chandra archive.

The researchers, led by Mustafa Muhibullah of the University of Alabama, identified 84 such objects, which surprised scientists as they had never encountered a group of objects behaving this way.

Muhibullah explained that these objects are distributed in both regions of active star formation and areas containing older stars. The team discovered these sources by identifying objects that appeared in Chandra images at low X-ray energies but disappeared in higher-energy images. This indicates that these objects emit far more low-energy X-rays than high-energy ones.

Since low-energy X-rays are adjacent to energetic ultraviolet radiation on the electromagnetic spectrum, the researchers determined that these sources also generate significant amounts of ultraviolet radiation.

The exact nature of these objects remains unclear, but the team suspects they may involve a black hole, neutron star, or white dwarf pulling material from a companion star. The heated material from the companion star then produces X-rays before falling onto the white dwarf or neutron star or into the black hole. While similar binary systems have been observed before, they have not exhibited the bright ultraviolet radiation and low-energy X-rays previously detected.

Muhibullah explained that these clandestine X-ray sources are among the most energetic objects in galaxies, and their discovery may help solve two cosmic mysteries at once. One mystery is the identification of potential Type Ia supernova explosions, which are crucial for measuring the expansion of the universe. Another mystery is the stripping of electrons from gas between stars in some galaxies, an essential factor in understanding the formation of stars and the life cycles of galaxies.