Complex sentence: After studying the Hydrogen alpha emission lines in the spectra of all six, it is shown that these emission lines are made up of multiple lines, meaning that the Peas have several chunks of gas and stars moving at large velocities relative to each other.
Split into simpler sentences: After studying the Hydrogen alpha emission lines in the spectra of all six, it is shown that these H alpha emission lines are made up of different lines. The multiple lines mean that the Peas have several chunks of gas and stars moving at large velocities relative to each other.