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Observations of jets from stellar-mass sources located in our Galaxy offer a unique opportunity to study the dynamical evolution of relativistic jets on time scales inaccessible for active galactic nuclei jets, with implications for our understanding of the dynamics and energetics of relativistic jets from Galactic x-ray binaries and active galactic nuclei. We review recent observations of X-ray jets from Galactic black hole candidates. Spatially resolved X-ray spectra from SS 433 have provided evidence for re-heating in a hadronic jet and may offer an observational probe of jet collimation. A large-scale jet from the now quiescent transient 4U 1755–33 appears to indicate continual jet formation over a period of 10–30 years. Detection of a jet from XTE J1550–564 has provided the first direct measurement of gradual deceleration of a jet from a black hole and strong evidence for the re-energization of jet particles to energies up to 10 TeV at sites far from the jet origin. [Copyright &y& Elsevier]

We present new optical and Chandra observations of the field containing the ultraluminous X-ray source NGC1313 X-2. On an ESO 3.6 m image, the Chandra error box embraces a R=21.6 mag stellar-like object and excludes a previously proposed optical counterpart. The resulting X-ray/optical flux ratio of NGC 1313 X-2 is ∼500. The value of fX/fopt, the X-ray variability history and spectral distribution indicate a luminous X-ray binary in NGC 1313 as a likely explanation for NGC 1313 X-2. The inferred optical luminosity (L≈105L◎) is consistent with that of a ≈10M◎ companion. [Copyright &y& Elsevier]