🪐intro to astronomy review

Balmer lines

Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025

Definition

Balmer lines are a series of spectral line emissions of hydrogen that occur when an electron transitions from a higher energy level (n > 2) to the n=2 energy level. They are prominent in astronomical spectroscopy and are used to identify and analyze stars' compositions and properties.

5 Must Know Facts For Your Next Test

  1. The Balmer series includes visible wavelengths, which is why these lines are often observed in the spectra of stars.
  2. The most commonly seen Balmer lines include H-alpha (656 nm), H-beta (486 nm), H-gamma (434 nm), and H-delta (410 nm).
  3. Balmer lines are named after Johann Balmer, who first derived their mathematical formula in 1885.
  4. These lines are crucial for determining the temperature and composition of stellar atmospheres.
  5. In hotter stars, Balmer lines appear stronger because hydrogen atoms are more likely to be ionized at high temperatures.

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