Stellar spectra started with the amount of hydrogen found in the star's spectrum and started with the letters A through Q. What are the current letters used to classify stellar spectra?
What will be an ideal response?
OBAFGKM
You might also like to view...
Electromagnetic waves of all wavelengths are collectively known as ________.
A. the electromagnetic spectrum B. the visible spectrum C. blackbody radiation D. white light E. a continuous spectrum
What method does "stars that fade" refer to?
A: Transits B: Radial velocity C: Astrometry D: Microlensing E: Direct imaging
A baseball leaves the bat with a speed of 47 m/s and an angle of 45° above the horizontal. A 5.0-m-high fence is located at a horizontal distance of 137 m from the point where the ball is struck. Assuming the ball leaves the bat 1.0 m above ground level, by how much does the ball clear the fence?
a. 59.7 m b. 47.7 m c. 49.7 m d. 121 m
Bottles of perfume sometimes have thick glass (n = 1.5) walls which give the impression the volume is larger than it really is. Assume a cylindrical bottle with an inner radius of 1.0 cm and an outer radius of 2.0 cm. What percentage of the apparent volume is the real volume?
a. 95% b. 60% c. 80% d. 64% e. 75%