Aims. We evaluate thermal stresses in small, spherical, andhomogeneous meteoroids with elastic rheology and regular rotation. Thetemperature variations are caused by the absorbed sunlight energy beingconducted into the interior layers of the body. Our model assumesarbitrary thermal conductivity value, but restricts itself to alinearized treatment of the boundary conditions of the heat diffusionproblem. We consider the diurnal insolation cycle only as if the bodywere in a fixed position along its heliocentric orbit. This constrainsthe upper limit to the object size to which our modeling is applicable.Methods. We derive analytical expressions for the components ofthe thermal stress tensor throughout the body. Using two sets ofmaterial properties (ordinary and carbonaceous chondrites), we studythe conditions required for material failure caused by thermal stressleading to fission. Results. Our results indicate that the onset of thermal failurein the meteoroid depends on a number of parameters including theheliocentric distance, the size, the rotation frequency, and theorientation of the spin axis with respect to the solar direction. Inour case, we find large, centimeter- to meter-size, slowly rotatingmeteoroids or those with a spin axis pointing towards the Sun or both,are the most susceptible to the thermal bursting. This may haveimplications for the (i)size distribution of meteoroids invarious streams depending on their heliocentric orbit and the physicalcharacteristics of their parent bodies; (ii)orbital distributionof sporadic complexes of meteoroids in the planet-crossing zone; and/or(iii)fate of fragments released during comet disintegrationevents, especially those with low perihelia (e.g., Kreutz class). Key words: meteorites, meteors, meteoroids - minor planets,asteroids: general - methods: analytical
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