AST201H5 Lecture Notes - Blueshift, Mass Number, Continuous Spectrum

Why do astronomers need different telescope designs to observe across the electromagnetic spectrum?

A) New telescopes incorporate new technology to increase their efficiency.

B) Telescopes have to adapt to the greater distortion of the atmosphere at shorter wavelengths.

C) Photons of different energy behave differently and require different collection strategies.

D) Light pollution is worse at radio wavelengths than visible wavelengths.

E) Astronomers and engineers enjoy the challenge of making new telescope designs.

The spectra of most galaxies show redshifts. This means that their spectral lines
(a) always are in the red part of the visible spectrum.
(b) have wavelengths that are longer than normal.
(c) have a higher intensity in the red part of the spectrum.
(d) have wavelengths that are shorter than normal.