The Mystery Of The Exploding Star

The Mystery Of The Exploding Star

In addition to sporting the heavy mass of 130 to 250 times that of our Sun, candidate progenitor stars for pair-instability supernovae must also have slow to moderate rotation rates, as well as a very low metallicity. Low metallicity means that the candidate progenitor star for such special, catastrophic, and weird supernovae must be made up almost entirely of hydrogen and …

Stellar Ghosts Haunt Stars

Stellar Ghosts Haunt Stars

Observing Type Ia supernovae must be accomplished quickly. This is because they flare into existence, and then dim to darkness, within only a few months. In order to study supernovae that have long since faded, and the stellar white dwarf ghosts that created them, Dr. Kirby and his colleagues used a technique informally named galactic archaeology. The term galactic archaeology refers to …

Fatal Attractions Among The Stars

Fatal Attractions Among The Stars

All of the stars in the observable Universe, both large and small, live out their entire nuclear-fusing main-sequence “lives” by keeping a very delicate and necessary balance between two ancient foes–gravity and radiation pressure. The main-sequence refers to hydrogen-burning stars on the Hertzsprung-Russell Diagram of Stellar Evolution. Main-sequence stars still have enough nuclear-fusing hydrogen fuel to keep themselves bouncy against the …

Matter Gone Missing

Matter Gone Missing

The Universe is thought to have been born about 13.8 billion years ago in the form of an exquisitely small searing-hot broth composed of densely packed particles–generally simply referred to as “the fireball.” Spacetime has been growing colder and colder ever since, as it expands–and accelerates as it expands–from its original furiously hot and glaringly …

stellar nucleosynthesis

stellar nucleosynthesis

Today, our Sun is still sufficiently youthful and bouncy to go on burning hydrogen in its heart by way of nuclear fusion–which continually creates heavier and heavier atomic elements out of lighter ones (stellar nucleosynthesis). But our Sun’s looks will change when it finally begins to run out of its necessary supply of hydrogen fuel. At …