School Notes
Date posted: Dec 13, 2019
Astronomers Study Stellar Origins of Carbonaceous Dust
BC/ISR astronomer Kathleen Kraemer and her colleagues have published a paper on evolved stars, much older than our Sun, using spectra from NASA’s airborne observatory SOFIA. The group investigated the mineralogy of the gas and dust being ejected from these stars that may be a dominant source of the carbon in the Universe. They found distinct differences in the kind of dust grains produced depending on the evolutionary phase of the star. The “Miras”, the oldest stars in this stage, create copious amounts of amorphous carbon dust (soot), while “semi-regulars” generate more silicon carbide (SiC). Since these dust grains are ejected out into interstellar space, they can be recycled into new stars and planets in the future, thus increasing the amount of carbon and other elements available for the building blocks of life.
The full paper on their results can be found in “Stellar Pulsation and the Production of Dust and Molecules in Galactic Carbon Stars” by Kraemer et al. 2019, available at