Two types of jets and origin of macrospicules

Comparison between observations of macrospicules and numerical jet models obtained in our previous one-dimensional hydrodynamic simulations suggests that H macrospicules and EUV macrospicules unseen in H have different physical origins. H macrospicules are produced by pressure gradient force at the bright point in the middle or in the upper chromosphere. On the other hand, EUV macrospicules unseen in H are produced by shock waves which originate from network bright-points in the photosphere or in the low chromosphere and have propagated through the chromosphere. An essential difference between the two types of macrospicules is the density ratio between macrospicules and the corona. The critical parameter causing this difference is the height of bright points. The general relation between the density in jets (including also regular spicules) and the height of bright points is discussed.