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We have analyzed four epochs of H$\alpha$ and [S~II] HST images of the HH~1/2outflow (covering a time interval from 1994 to 2014) to determine propermotions and emission line fluxes of the knots of HH~2. We find that our newproper motions agree surprisingly well with the motions measured by Herbig \&Jones (1981), although there is partial evidence for a slight deceleration ofthe motion of the HH~2 knots from 1945 to 2014. We also measure thetime-variability of the H$\alpha$ intensities and the [S~II]/H$\alpha$ lineratios, and find that knots H and A have the largest intensity variabilities(in $1994\to 2014$). Knot H (which now dominates the HH~2 emission) hasstrengthened substantially, while keeping an approximately constant[S~II]/H$\alpha$ ratio. Knot A has dramatically faded, and at the same time hashad a substantial increase in its [S~II]/H$\alpha$ ratio. Possibleinterpretations of these results are discussed.

The time evolution of HH~2 from four epochs of HST images