Briefly explain why white-dwarf supernovae are useful for measuring cosmic distances
What will be an ideal response?
They all come from explosions of white dwarfs that reach the white-dwarf limit of 1.4 solar masses. As all white dwarf progenitors have the same mass, we expect them all to have the same luminosity. Observations of white-dwarf supernovae for which we can measure distance independently confirm that they all have the same luminosity. Because we know their luminosities, we can use their apparent brightnesses to determine their distances from the luminosity-distance formula. Another advantage is that white dwarf supernova can be as bright as entire galaxies so that they can be detected in very distant galaxies.
You might also like to view...
A Schottky defect in an ionic material is a cation and anion _____________.
Fill in the blank(s) with the appropriate word(s).
Heat Engines: A heat engine has an efficiency of 35.0% and receives 150 J of heat per cycle.(a) How much work does it do in each cycle?(b) How much heat does it "waste" in each cycle?
What will be an ideal response?
The special theory of relativity was developed
A) almost in its entirety by Max Planck. B) almost in its entirety by Albert Einstein. C) almost in its entirety by Erwin Schroedinger. D) in its entirety by Planck, Schroedinger, and Einstein. E) by Planck, Schroedinger, Einstein, and many other scientists.
Potential energy can be defined only for non-conservative forces
Indicate whether the statement is true or false