Stellar parallax is
A standard candle is
Absolute magnitude is
Relative magnitude is
In 1989 the satellite Hipparcos was launched primarily for obtaining parallaxes and proper motions allowing measurements of stellar parallax for stars up to about 500 parsecs away, which is about ____ times the diameter of the Milky Way Galaxy.
An object emits thermal (blackbody) radiation with a peak wavelength of 250nm. How does its temperature compare with the Sun?
The "normalized intensity" of a Sun-like star situated one parsec from Earth would be 4πI = 1. What is 4πI for a star with 100 times the Sun's energy output that is situated 10pc from Earth?
An orbiting satellite makes a circular orbit 5 AU from the Sun. It measures a parallax angle of 0.2 of an arcsecond (each way from the average position). What is the star's distance?
A star that is increasing it's temperature while maintaining constant luminosity is
The range of wavelength for visible light is between
Based on the HR diagrams and images in stars shown in the materials, a very large red supergiant has a diameter that is about ____ greater than a small white dwarf.