Types of Stars

1. Types of Stars Reverend Pemberton

2. WWK • Learn about the different types of stars and their classifications.

3. Vocabulary • Stellar classification- classification of stars based on their spectral characteristics. • Spectral class- acategory for classifying a star, as A star or G star, according to features of its spectrum, as its shape as a function of temperatureand wavelength and its absorption spectrum, that indicate thesurface temperature of the star and the presence of particular atomsormolecules in its outerlayers.

4. Current Classification • Stars are currently classified using the letters: O, B, A, F, G, K and M. • O being the hottest, M being the coolest.

5. Morgan-Keenan System • O- hottest “blue” 25,000+ K • B- “blue-white” 11,000-25,000 K • A- “white” 7,500- 11,000 K • F- “Yellow-white” 6,000-7,500 K • G- “Yellow” 5,000-6,000 K • K- “Orange” 3,500-5,000 K • M- “Red” under 3,500 K

6. Types • There are seven different types of stars. • 1. Main Sequence Stars- all stars begin this way, it is the beginning of the nuclear fusion. • 2. Red giants- Our sun will eventually transition into this type. • 3. White dwarfs- expanding red giants, these stars spin out until the core is all that remains.

7. Types- continued • 4. Neutron stars- stellar remnant of a past star. • 5. Black holes- these usually form when a star reaches the end of its cycle and begins to collapse in on itself. • 6. Brown dwarfs- these are failed stars, they form the same as regular stars but never get enough mass to achieve fusion. • 7.Variable stars- “twinkle” due to changing brightness because of constant expansion and contraction.

10. White dwarf