Effect of Supernovae on the Local Interstellar Material

Abstract

A range of astronomical data indicates that ancient supernovae created the galactic environment of the Sun and sculpted the physical properties of the interstellar medium near the heliosphere. In this paper we review the characteristics of the local interstellar medium that have been affected by supernovae. The kinematics, magnetic field, elemental abundances, and configuration of the nearest interstellar material support the view that the Sun is at the edge of the Loop I superbubble, which has merged into the low density Local Bubble. The energy source for the higher temperature X-ray emitting plasma pervading the Local Bubble is uncertain. Winds from massive stars and nearby supernovae, perhaps from the Sco-Cen Association, may have contributed radioisotopes found in the geologic record and galactic cosmic ray population. Nested supernova shells in the Orion and Sco-Cen regions suggest spatially distinct sites of episodic star formation. The heliosphere properties vary with the pressure of the surrounding interstellar cloud. A nearby supernova would modify this pressure equilibrium and thereby severely disrupt the heliosphere as well as the local interstellar medium.

The wavelength dependence of interstellar polarization in the Local Hot Bubble

“…been shocked by past supernovae Welty et al (1999), as is believed to be the case for the LHB (Berghöfer & Breitschwerdt 2002;Frisch & Dwarkadas 2017), and is supported by UV spectroscopic measurements of nearby stars (Frisch et al 2011).…”

“…The LHB is the result of shock waves and stellar winds from ancient supernova explosions sweeping up gas and dust as they expand (Frisch & Dwarkadas 2017). Berghöfer & Breitschwerdt (2002) estimate that there have been 20 supernova explosions in this region of space within the last 10-20 Myr.…”

The Far-infrared Polarization Spectrum of ρ Ophiuchi A from HAWC+/SOFIA Observations

“…In regions where the magnetic field energy density is subdominant to the kinetic energy of the matter, gas dynamics will influence magnetic field morphology. This effect has been observed for Hi shells (Heiles 1998;Fosalba et al 2002;Santos et al 2011;Frisch & Dwarkadas 2017;Soler et al 2018) as well as at the edges of Hii regions (Pavel & Clemens 2012;Santos et al 2012Santos et al , 2014Planck Collaboration Int. XXXIV 2016).…”

60 Fe deposition during the late Pleistocene and the Holocene echoes past supernova activity

“…| supernova | ISM | accelerator mass spectrometry | deep-sea sediments T he temperature and particle density of the interstellar medium (ISM) is shaped by winds from massive stars and stellar explosions. Near the solar system (SS), supernovae (SNe) have created a network of filaments, shells, and superbubbles (1)(2)(3)(4)(5)(6)(7). Superbubbles represent low-density cavities in space with typical densities of ∼0.005 hydrogen atoms per cm 3 (10 −26 g•cm −3 ) and exist for tens of millions of years.…”

“…These are partially ionized individual clouds within the much-lower-density LB material, filling between 6 and 19% of the LB volume (4). Because the SS is moving at a considerable velocity sometimes exceeding 25 km•s −1 relative to these clouds, it has encountered them regularly, with the first encounter sometime between 44 and 150 ky BP (1,6,7). For a cloud length of ∼1 pc the cloud transit time becomes on the order of 40 ky.…”