The big picture: Scientists have discovered an unusual galaxy that seems to have experienced the cosmic equivalent of a road accident. Known as NGC 5084, this star system exhibits not just one but two sets of powerful X-ray plumes emanating from its core… and that’s not even the most peculiar aspect.
Hiding within archival data from NASA’s Hubble Space Telescope and other observatories, researchers found another remarkable feature of NGC 5084: a small, tilted dust disk spinning around its center at a 90-degree angle to the galaxy’s overall rotation. This suggests the inner disk is, “in a sense,” laying on its side compared to the larger galaxy enveloping it.
The team suspects that a significant disruptive event—or a series of events—must have massively altered NGC 5084. They hypothesize that this could have resulted from a violent collision with another galaxy or the outburst of superheated gas from the top and bottom of the galactic disk.
According to lead researcher Amanda Borlaff, analyzing data across the electromagnetic spectrum was like examining forensic evidence at a crime scene. Integrating the multi-wavelength clues unveiled that NGC 5084 underwent dramatic transformations relatively recently.
Typically, large galaxies release their X-ray energy in an approximately spherical pattern. However, the concentrated plumes suggest a disruption to this customary arrangement.
The comprehensive findings were published on December 18 in The Astrophysical Journal.
Co-author Pamela Marcum said that discovering two distinct pairs of columnar X-ray features in a single galaxy is “exceptional,” noting that their cross-shaped formation, coupled with the tilted disk, offers unique insights into the galaxy’s turbulent history.
Even as the chaotic structure of NGC 5084 remains baffling, its discovery underscores the power of modern techniques in unearthing new findings from old data. Some of these observations are nearly 30 years old.
In this case, researchers amplified extremely faint signals buried in archival data using advanced image processing, which revealed diffuse features previously undetected. This innovative technique is named SAUNAS (Selective Amplification of Ultra Noisy Astronomical Signal).
In conclusion, while the root cause remains unclear, solving the puzzle of NGC 5084’s restructuring promises to yield valuable insights into how galaxies transform through violent events.