Astrophysical Phenomena - Class Lecture Notes

Astrophysical Phenomena - Class Lecture Notes Intro to Astrophysical Phenomena Astronomical event therefore includes things in space that we can study or explore including stars, planets, black holes, and supernovae amongst others. - It has done so, and also such phenomena assist individuals in comprehending nature of the universe. Some key points to remember:Some key points to remember: ● The universe a large and there is so much to explore and learn about it. ● Thereby, the observations can be done through telescope as well as other assisting instruments. Stellar Evolution ● ● ● ● ● Protostar: A young star that's still gathering mass Main Sequence Star: The longest stage of a star's life, during which it fuses hydrogen into helium Red Giant: A star that has exhausted its hydrogen and is now fusing helium White Dwarf: The remnant of a red giant after it sheds its outer layers Supernova: A massive explosion at the end of a star's life Black Holes Black holes are areas in space where gravity is so intense that not even light can be pulled out from it. They are developed from the remains of large stars when they burst as supernovae. ● Event Horizon: The boundary beyond which nothing can escape ● Singularity: The point at the center of a black hole where gravity is infinitely strong ALSO ● ● Black holes can be detected through their effect on nearby objects They can merge to form larger black holes Supernovae ● Types: Type I and Type II supernovae ● ● Can outshine entire galaxies for a short period Responsible for creating heavy elements in the universe Exoplanets: These are planets that revolve round stars other than the sun They are also known as ‘extra-solar’ planets. Knowledge of Exoplanets give us insights about formation of planets and about the possibility of life on other planets. ● ● Detection Methods: Transit method, radial velocity method, and direct imaging Thousands of exoplanets have been discovered ** Cosmic Microwave Background (CMB) ** The CMB is the afterglow radiation from the Big Bang. It provides a snapshot of the universe when it was just 380,000 years old. ● Discovered in 1965 by Penzias and Wilson ● Helps us understand the early universe and its evolution ** Gamma-Ray Bursts (GRBs) ** ● ● ● Types: Long-duration and short-duration GRBs Believed to be associated with the collapse of massive stars or the merger of neutron stars Can release more energy in a few seconds than the sun will in its entire lifetime Quasars: are supermassive structures containing highly luminous objects in the core of a distant galaxy usually powered by a black hole. - It is among the farthest and active bodies in the universe. ● ● Emit massive amounts of energy Can help us understand the early universe