21. Gravity waves can propagate in the absence of matter, so they're not analogous to sound.22. This was the first proof, indirect though it was, of the existence of gravity waves . 23. :There are gravity waves , at least in theory. 24. Barish thinks that gravity waves might help map this so-called dark matter for the first time. 25. The long, vertical dark lines show where the troughs of gravity waves have roughened the surface. 26. Equatorial gravity waves can be either westward-or eastward-propagating. 27. "We don't yet know, but these atmospheric gravity waves may affect the process of ozone destruction," 28. According to relativity theory, that stirring action should send out a weak signal of gravity waves . 29. Gravity waves aligned normally to the direction of the wind can show wide, near-parallel cloud strips.30. In 1984 it was demonstrated that the star's variability is due to nonradial gravity wave pulsations.
