We report here the discovery of a 30-chain of embedded Herbig-Haro (HH) objects in the rho Ophiuchi dark cloud. These HH objects were first detected during a deep K_S-band observation (completeness magnitude for point source~19) made with NTT/SOFI. We confirm their nature with follow-up observations made with H_2 v=1-0 S(1) narrow-band filter. We argue that they belong to two different jets emanating from two Class I protostars: the main component of the recently resolved subarcsecond radio binary YLW15 (also called IRS43), and IRS54. We propose also to identify the [S II] knot HH224NW1 (Gomez et al 1998) as emanating from a counterjet of YLW15. The alignment between these HH objects and the thermal jet candidate found in YLW15 by Girart et al. (2000) implies that this jet is not precessing at least on timescale ~(2-4)x1E4 yr.
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