Researchers from the Max Planck Institute for Extraterrestrial Physics (MPE) have identified an interstellar tunnel within the Local Hot Bubble (LHB) that may link our solar system to the constellation Centaurus. This finding was made using data from the eROSITA All-Sky Survey.
The LHB, a cavity measuring approximately 1,000 light-years across, is characterized by its low density and high temperatures, reaching around a million Kelvin. This region is filled with a million-degree gas that emits soft X-rays, making it a subject of extensive study for over 50 years.
According to the researchers, the newly discovered tunnel could connect the LHB to neighboring superbubbles, potentially forming a vast network of hot gas. The eROSITA data revealed significant temperature variations within the bubble, suggesting that past supernova explosions have played a role in shaping its structure.
Michael Freyberg, a study author, emphasized the importance of eROSITA’s improved sensitivity and unique survey strategy, which allowed for the detection of this tunnel. However, the current understanding of this feature remains limited, particularly due to interference from other large structures near the galactic center.
While the extreme temperatures of the LHB facilitate X-ray emissions detectable by telescopes, its low density presents challenges for heating objects within it. The eROSITA telescope, positioned 1.5 million kilometers from Earth, offers a clearer perspective, minimizing the interference caused by Earth's atmosphere.
Further investigations are anticipated to enhance understanding of the LHB and its connections to the broader cosmic environment.