Variable Stars, Star Clusters, and Stellar Death PDF

Variable Stars, Star Clusters, and Stellar Death Explore the mysteries of variable stars, star clusters, and the dramatic ends of stellar lives. Variable Stars, Star Clusters, and Stellar Death Embark on a journey through the celestial tapestry, exploring the mysteries of variable stars, star clust...

Variable Stars, Star Clusters, and Stellar Death Explore the mysteries of variable stars, star clusters, and the dramatic ends of stellar lives. Variable Stars, Star Clusters, and Stellar Death Embark on a journey through the celestial tapestry, exploring the mysteries of variable stars, star clusters, and the ultimate fate of stars. Test Your Stellar Knowledge 1. What is a variable star, and what causes its brightness to change? 2. What are the two main types of star clusters, and how do they differ? 3. Describe the different ways a star can die, depending on its mass. 4. What are some of the remnants left behind after a star dies? Understanding Variable Stars Intrinsic Variability 1 Changes originate within the star itself, often due to pulsations or eruptions. 2 Extrinsic Variability Variations caused by external factors, like eclipses from companion stars or stellar winds. Light Curve Analysis 3 Studying the changing brightness over time reveals crucial information about the star. sun as variable star Pulsating Variable Stars Cepheid Variables Stars with a predictable pulsation period, directly linked to their luminosity. Used as cosmic distance indicators. RR Lyrae Variables Similar to Cepheids, but with shorter periods. Found in globular clusters and helpful for studying galactic structure. Cepheid Variables: Cosmic Yardsticks These stars pulsate regularly, their brightness fluctuations directly related to their luminosity. Astronomers use this relationship to determine distances to galaxies, making them invaluable for studying the vast expanse of the universe. RR Lyrae Variables RR Lyrae variables are pulsating stars that exhibit a regular pattern of brightening and dimming. These stars are crucial for studying galactic structure, particularly in globular clusters. Cataclysmic Variable Stars 1 2 3 Novae Supernovae Dwarf Novae Explosive events caused by the More powerful explosions, marking the Similar to novae, but less energetic. accretion of matter onto a white dwarf, end of massive stars. They leave behind They occur in binary systems with a leading to a sudden increase in remnants like neutron stars or black white dwarf accreting material. brightness. holes. Click here: Variable Star Exploring Star Clusters A star cluster is a group of stars that share a common origin and are gravitationally bound for some length of time. Gravitational Binding Stellar Evolution Types of Clusters Stars held together by their mutual Studying star clusters provides Globular clusters are old and gravitational attraction, creating a insights into stellar evolution, as stars spherical, while open clusters are dense collection. within the cluster form at roughly the younger and less de same time. Click here: Star Clusters Famous Star Clusters The Pleiades Omega Centauri Also known as the Seven Sisters, this open cluster is a prominent The largest and brightest globular cluster in the Milky Way galaxy, sight in the night sky, a testament to the celestial beauty of star Omega Centauri (NGC 5139), is one of the clusters visible without formation. a telescope. Globular Clusters and Open Clusters Globular Clusters Open Clusters Ancient, tightly packed collections of stars, containing hundreds Loosely bound groups of stars, typically containing a few of thousands to millions of stars. hundred stars, found in the disk of the galaxy. The Life Cycle of Stars 1 Nebula Stars begin as vast clouds of gas and dust. These nebulae are composed primarily of hydrogen and helium, with traces of heavier elements. 2 Protostar Gravity pulls the material in a nebula together, forming a dense core called a protostar. This core heats up as it collapses, eventually reaching temperatures high enough to initiate nuclear fusion. 3 Main Sequence Once nuclear fusion begins, the star enters its main sequence phase. During this stage, the star fuses hydrogen into helium, generating energy and maintaining its stability. 4 Red Giant After exhausting its hydrogen fuel, the star expands and cools, becoming a red giant. The core continues to contract, and heavier elements are created through fusion. 5 Stellar Death The final stage of a star's life depends on its mass. Low-mass stars become white dwarfs, while massive stars explode as supernovae, leaving behind neutron stars or black hole. Click here: Life Cycle of Star Supernovae and Stellar Remnants Supernovae Neutron Stars Black Holes White Dwarfs The explosive death of Extremely dense, rapidly Regions of spacetime where Dense, hot remnants of low- massive stars, scattering spinning objects formed from gravity is so strong that mass stars, consisting heavy elements into space. the collapsed cores of massive nothing, not even light, can primarily of carbon and stars. escape. oxygen. Conclusion: Unlocking the Mysteries of the Universe The study of variable stars, star clusters, and stellar death provides a window into the workings of the universe, unlocking secrets of stellar evolution and the origins of matter. Variable Stars, Star Clusters, and Stellar Death Explore the mysteries of variable stars, star clusters, and the dramatic ends of stellar lives. Test Your Knowledge: Start Quiz THANK YOU! -Ma'am Micaela B. Melgar